OzVMX Forum
Marque Remarks => Yamaha => Topic started by: Colin Jay on August 15, 2016, 11:45:23 am
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A question for the Yamaha experts. What year were the TT350 and XT350 released in Australia?
I am currently running a 1987 XT250TT (DOHC) in the Pre-1990 class of the SA Reliability Trials Series. Although it has proved to be a nice light bike and quite tough, the poor little thing struggles to pull my weight (135kg fully dressed to ride). I think a TT350 (or even a XT350) would probably be a bit better for some one my size. I would like to build up a "new' bike, either TT or XT350 for next years series, and it would be great if I could get a pre-85 bike that would be eligible for VERI vinduros. I have always thought that the DOHC TT/XT350s were released in 1983/4 but I can find any reference on the net to any thing pre-1985.
Thanks in advance, Col
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1986 model for TT350. I am seeing some references to 1985 model XT350 but i am not sure on the accuracy. Either way not pre 85 eligible.
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IIRC:
Twin cam XT250 first came out in mid-late 1983.
Twin cam TT250 first came out in mid-late 85, not sure if they were designated as 85 or 86 models.
The TT350 (they were all twincam...) first came out a month or two later than the twin cam TT250. Again, I'm not sure if the first ones were 85 or 86 models.
No idea on the XT350, sorry.
I also thought the twin cam TT250s were one of VERi's "official blind eye" bikes? There's certainly been plenty of them ridden in Vinduros over the years...
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The TT 350 and 250 (called 225 in USA) that looked like this were 86 models first. It is possible that they came out mid/late 85 ofcourse as the new models often came out before end of the year. Cylmers XT/TT manual says for 1985 onwards so i reckon that the XT350 may have come out a year earlier?
(http://assets.hemmings.com/story_image/456151-870-0.jpg?rev=2)
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i though the first ones came out in 1985 as i remember doing the 6 hours pony express on my 1985 XR250RF and racing against a guy on a TT350.
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Japanese Motorcycle History book shows XR350R and TT600 released for 1983 and TT350 for 1986.
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The 86 models could have been available mid '85.
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Online parts lists show the first XT350 being the 1985 model. Same lists show the first twin cam TT being 86 models.
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I checked the '85 24hr entries. No 350 yams entered in '85 but there was 2 in '86. Event is held in July.
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Thanks guys.
Since I am mainly after a bike to ride in the pre-1990 class in the SA Reliability Trials, I will start looking for a one that just meets the pre 1990 criteria, it would have been good to get one that was VERI eligible, but, I still have my Husky auto that I can ride in those events. If I wanted to cheat, I have a 1983 frame that I could rebuild my 1987 XT250 on but that is just way to much effort.
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I seriously doubt that anyone would care about the one difference between the 83/84 XT250 and the 87 XT250...
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I am currently running a 1987 XT250TT (DOHC) in the Pre-1990 class of the SA Reliability Trials Series
Cool! Got any pics or anecdotes about your efforts thus far?
Tex
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The bike was given to me the day before Christmas 2014 in a very sorry state. The engine had been dusted, the rear suspension was flogged out, and the poor little thing was suffering all the usual problems of a 30 year old trail bike. However, as the basics were ok, I invested about $1000 in repairing it and getting fit for rego. After riding it a few times, I remembered what a sweat little bike these twin cam XT's were.
Although I "retired" from racing in 2012 after busting myself up badly on the APC rally of that year, I entered the Rally (non-comp) class of the 1st rnd of this years SART at Marrabel (Gawler MCC) just to have a fun ride. The little XT put in a great performance. Its light weight and good steering made it a blast to ride in the tight comp sections, and the engine even had enough grunt to pull my considerable bulk (135kg ready to ride) up the hills. If there was/is a down side it is that the rear suspension just can handle my weight when pushing it on the fast sections. Overall, I had a blast and thoroughly enjoyed the day and would have loved to have ridden a 2nd lap of the course.
Having had such a good time at Marrabel, I entered for Class P (Pre-1990 comp) for rnd 2 in the Barrosa Valley (Keyneton MCC) as it was going to be a daylight only event. The Keyneton boys alway put on a great event and the paddock sections were brilliant. I had a ball on the first lap and the little XT handled it well. About half way into the first paddock section on the 2nd lap, I went down the low side in a fast RH bend, braking my front brake lever clean off. Not having a slare lever, I carried on and roade the rest of the lap, about 70km including 5 more special paddocks without a front brake. Surprisingly, when I looked at my section times afterwards, I was faster in some of the tight paddocks on the 2nd lap with no brakes that I was on the first lap. It just goes to show that if you pick good lines and ride smoothly, you real do go faster. About the only issue I had with the little XT, apart from the broken brake lever, was with the gearing. I was consistently either changing up into 2nd gear, only to have to change straight back down to 1st, or reving the tits off the poor little thing in 1st gear, in one paddock I looked down at the tacho and it was showing 9000+rpm. I ended up 3rd in Class P (4 entries including 1 sidecar) and somewhere near last overall, but I had a great time.
Riding the sand in the final paddock section of the course at rnd 2.
(http://i150.photobucket.com/albums/s120/coljay/13327462_1118012384925990_8391580874188096196_n_zpsgjrvuyms.jpg)
I didn't ride rnd 3 The Robertstown Two Day or rnd 4 the 24Hr as my masochistic tendencies have diminished a bit over the passed few years.
Having had a good ride in the Barrosa, I entered for rnd 5, the Gill Harris 6Hr at Mallala (Leveis MCC). As my finish time was scheduled to be well after dark, around 8pm, I fitted a 55/100 QH headlight globe and a LED aux light above the head light to show me the way after dark. I also fitted a 14T countershaft sprocket in place of the std 15T to trying make 2nd gear more usable in the tight scrub paddocks that Mallala is famous for. A fair bit of rain leading up to the event saw near perfect conditions on the day, with zero dust and only a couple of slippery patched in the first and 2nd paddock sections. I had a great ride, riding in company with the 2 other solo competitors in Class P. Again the little XT performed well above what you would expect from a basic trail bike. The change to the 14T countershaft made the gearing spot on for the tight scrub paddocks. After gating in 1st, it was straight up to 2nd most of the paddock sections (2 to 3km in length), in a few of the fast a bit I even managed to hook 3rd gear for a while. I ended up with 2nd place in Class, only because one of the other riders lost 600 points for not putting his foot on the ground at the stop sign as you left main control. Overall I was 83rd or 84th just a few places off of last, but I had finished and thats was good enough for me.
After the finish at Mallala
(http://i150.photobucket.com/albums/s120/coljay/malalla%20XT250_zpsrjistyeq.jpg)
I have entered the River Murray RT, which is on Saturday down at Manum, the weather looks like it could be wet, but it is another daylight only event and hopefully it will be as much fun as my last two events. That will be the end of the season for me this year as I am COC for the 7th and final round at Clare.
So far the little XT has performed way better than I could ever have expected. Its light weight and small size makes it a fun thing to ride in the tight scrub paddocks, and it goes fast enough for me. Yes the suspension is a bit soft and there is not a lot of travel at the rear, but it is miles ahead of the old XT500 that I rode in 2008/2009/2010. I have been in contact with a friend who runs a bike shop and he has half a dozen old 1980's TT350's. I will be heading up to see him in a few weeks time to see if I can pickup good one and enough bits to build up a descent bike for next year. I will be a sad thing to pension off the 250, but it would just be cruel to keep abusing the poor little thing.
A final pic of the baby XT in action, taken while check riding the course for the 3rd round of the SAORC at Auburn in June.
(http://i150.photobucket.com/albums/s120/coljay/IMG_0634_zpsamiebdgi.jpg)
Col
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Nothing wrong with the reliability of the little XT then. Good stuff.
I've got a TT350 that I've just about finished rebuilding. I'm just waiting on the new piston to get here.
Unfortunately, the bloke I got it from thought it was a good idea to try and glue the inlet manifolds back together with something that resembled blutac! No surprise then that the motor got dusted. It still went ok and didn't blow smoke but was low on compression.
It's got new inlet manifolds, cleaned and rebuilt carbs, reconditioned and ported head, new airfilter, new swingarm and linkage bearings, new brake pads and rear shoes, rebuilt forks, stripped and repainted frame and swingarm, new OEM front and rear guards, new tail light, new seat cover, new swingarm protector and chain guide, good chain, sprockets and tyres, new grips and cables cleaned and lubed.
If you're interested in a "ready for the next decade" TT350, I could be tempted to sell.
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First model TT350 was 86, I bought a runout 85 model TT600 on special from stoney creek at the end of 85. When i took it back for its first service just before Christmas 85 there was a new 350 on the floor then. It looked mad at that time because of the air scoops, sort of like an MX bike and a road trail like somewhere in between, being a four stroke.
My 350 is serial numbered 1044, its manufacture date is 4/86.
Bullahdelah March 2015
(http://i1063.photobucket.com/albums/t512/oz555ktm/bulla%20brain%20t_zpsxt1xsrla.png)
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id be working on the 350 asap as I found them to be a significantly better off road bike than the xt 250.
the gearing is something you have allready found along with the shocker and all this is much better suited on the 350 being purpose built off roader the power is nice on the 350, pulling a higher gear everywhere and plenty of torque to allow short shifting. you should know this..you own a husky 8) ;D
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G'day there, just if I can add my 2 cents on this topic,
I wouldn't cross an XR350 (in particular the (85-86 RF/RG moodels) off my list either, they were and still are a top bike..
Cheers, Mark
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xr 350's are a great bike, probably the best all rounder bike of the 80's imo but spare supply is zero. even worse, each model has its own parts zone, they don't cross pollinate that well.
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The bike was given to me the day before Christmas 2014 in a very sorry state...
...it would just be cruel to keep abusing the poor little thing
Thanks for the great read and photos Col!
Tex
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xr 350's are a great bike, probably the best all rounder bike of the 80's imo but spare supply is zero. even worse, each model has its own parts zone, they don't cross pollinate that well.
You're pretty much right, I've had a bit to do with XR's for around 20 years now, and while I have found that some things from the RD/RE XR350's (83-84) interchange with the RF/RG (85-86) models, there's a lot that doesn't at the same time. See, the RF/RG versions have the single 35mm carby, which necessitates a different cyl head/airbox etc. They also have a dry sump lube system which means the oil pumps/cases are different, then the later motor has a 63.8mm stroke (353cc), compared to 61.3mm (339cc) for the 83-84 (different crank/piston etc).
Camshafts, barrels, clutches, stator/stator cover, and if you swap the entire trans over inc the bearings, it will swap, but it leaves a lot of stuff thats different too.
My advice if you were to consider an XR350 (which they are well worth it!), either try to locate a good one that doesn't need major work, or tap yourself into a parts supply for the hard to get stuff (like having a parts bike).
Happy bike hunting! ;D
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id be working on the 350 asap as I found them to be a significantly better off road bike than the xt 250.
the gearing is something you have allready found along with the shocker and all this is much better suited on the 350 being purpose built off roader the power is nice on the 350, pulling a higher gear everywhere and plenty of torque to allow short shifting. you should know this..you own a husky 8) ;D
I don't have to worry about shifting at all on my Husky, its an Auto!!
G'day there, just if I can add my 2 cents on this topic,
I wouldn't cross an XR350 (in particular the (85-86 RF/RG moodels) off my list either, they were and still are a top bike..
Cheers, Mark
I did consider the XR350 as I worked as a mechanic for a Honda dealer when they were released and found them to be a sweat ride. Unfortunately, good ones are harder to find and the parts situation makes them a bit of a harder resto than the TT350. I will see how I go next week when I go to check out what the TT's that the mate has are like.
Col
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:)
http://www.gumtree.com.au/s-ad/ipswich/motorcycles/honda-xr-350-vinduro-honda-xr-70-suzuki-lt-125-quad/1119626666
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I have been told some stuff for Xr350's is very hard to get. NLA as a genuine part and with no aftermarket option and not found on any other models, so i would certainly do your home work first with regard to parts availability on these.
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:)
http://www.gumtree.com.au/s-ad/ipswich/motorcycles/honda-xr-350-vinduro-honda-xr-70-suzuki-lt-125-quad/1119626666
Just had a look at that one, it's a 1983-84 twin carb model. Reasonable Nick for a 32-33 year old scoot. It would depend how she runs........ ;)
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I rode the little XT250 in it's last event, the River Murray Trial near Mannum on Saturday. A great ride, but a lot of deep sand which really highlighted the 250's power deficiency. The paddock sections were also full of deep whoops, which showed the folly of trying to ride a simple trail bike in these types of events.
(http://i150.photobucket.com/albums/s120/coljay/Mannum%202016_zpsrb3i8xxv.jpg)
Yesterday, I made the 800km round trip up to Broken Hill, and picked up the bare bones of a 1988 TT350 from the mate.
(http://i150.photobucket.com/albums/s120/coljay/TT350%2030-8-16_zpsmzs17umb.jpg)
Yes, it is as bad as it looks, the engine is locked up from having sat out in the weather, but it is a 1988 model and has the all important Compliance Plate needed for registration. I also got a later model rolling chassis which will be the donor bike for the wheels and body work. So many hours of fun to come to have it all ready for the start of the 2017 season in May next year.
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You all know the phrase " Assumptions make asses of all". Well, I have Assumed and ...
After removing the engine from the frame of my "new '88 TT350" this afternoon, I removed the head to find a bit of corrosion and the piston stuck but not to solidly that a good wack with a heave copper dolly could fix.
What I also noticed, was that the piston looked a bit small for a 350 and somewhat familiar, having rebuilt my XT250 engine earlier this year.
Now we need to back track a bit to yesterday morning when I was rummaging through the pile of dead/wrecked "TT350's". I was all excited to find a red framed one with matching engine and frame numbers, and only scratched through the grease dirt and grime on the Compliance Plate far enough to find the all important manufacture date, which was 8/88. It was a Woo Hoo moment, and I though that I had my "new" bike.
Now back to the present.
After being somewhat surprised by the size, or more to the point, the lack of size of the piston, I dug further through the grease dirt and grime on the Compliance Plate far to find the sad reality that the bike is a 1988 TT250! BUGGER!
(http://i150.photobucket.com/albums/s120/coljay/TT350%20comp%20plate_zpsxmocnrh1.jpg)
To compound the errors of my assumptions, I have had a good look at the donor rolling chassis, and you guessed it, yep, it's a TT250 as well!
So, I now have to decide from the following;
1. Stick with this bike and build up a nice little 250 with good suspension and just put up with the lower power output,
2. Ditch the whole thing and try and find a suitable Pre-1990 TT350, or
3, Build up this Pre-1990 eligible rolling chassis and find a 350 engine to slot into it! (I assume that the 350 engine will fit into the 250 frame, OH BUGGER I am making assumptions again!!)
There is a 4th option, can anyone tell me if it is possible to fit a 350 topend onto the 250 crankcases?
No matter which way I go from here, I will join the crowd and stand up and say,
"I have made an assumption and therefore I have made an ass of myself!"
Col
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bugger..the best laid plans....I don't believe its an easy swap to drop the 350 onto the 250 but I am not often right and I could be wrong again. I have a vague recollection of p platers wanting to 350 their 250 and it was a sticker job only. smarter yamaha lovers will get back to you with the low down shortly
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350 motor goes into 250 frame, no problem.
If you want a 350 motor, then you need a 350 motor. Cranks are different, cases are different...
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350 motor goes into 250 frame, no problem.
If you want a 350 motor, then you need a 350 motor. Cranks are different, cases are different...
Thanks for that.
I have been looking up parts in Zedder and found that the connecting rod, piston pin etc were different which ruled out grafting a 350 topend onto the 250 cases. I will try and get a 350 engine if i can't find a low cost completeish 350.
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I have decided to rebuild the bike with the 250 engine, although as we all know with projects, this could change tomorrow, or at the next swap meeting I go to if I find a 350 engine.
A few pictures of the condition of the engine top end;
(http://i150.photobucket.com/albums/s120/coljay/TT350%20head%201_zpslwqbik3z.jpg)
The corrosion is not as bad as it looks, most of it is very light and I think it will clean up ok. the important think is that the cam bearing surfaces in the head are all ok.
(http://i150.photobucket.com/albums/s120/coljay/TT350%20head%202_zpshjuik31n.jpg)
Looks bad, but most of it just wiped away with a rag, a decoke and valve job should be all that is required.
(http://i150.photobucket.com/albums/s120/coljay/TT350%20cylinder_zpsn6rphm1e.jpg)
Again, the corrosion isn't to bad, and when rebuilding engines of this age a rebore is on the cards anyway, so it is not going to be an issue.
I hope to have time to strip the bottom end in the next day or so, and if all is ok, will clean up the cased and rebuild the bottom end with all new bearings and seals.
Col
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sorry to butt in but I'm looking for a cylinder for a xt/tt 250 do you have one to spare? thanks
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I rode the little XT250 in it's last event, the River Murray Trial near Mannum on Saturday. A great ride, but a lot of deep sand which really highlighted the 250's power deficiency. The paddock sections were also full of deep whoops, which showed the folly of trying to ride a simple trail bike in these types of events.
(http://i150.photobucket.com/albums/s120/coljay/Mannum%202016_zpsrb3i8xxv.jpg)
Jeez, I reckon the bloke on the 2 valve XT250 would have done it tougher! :o
Tex
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my back hurts just thinking about it 8)
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Nah i reckon this would have been a piece of cake for him. He finished the 24hr this year which was in very, very bad muddy wet windy conditions with only 40 solos finishing out of over 100 starters (huge list of DNF's). Just goes to prove you can finish on anything if you set your mind to it.
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Adam (the guy on the 2 valve) is a good rider and is deceptively fast on the old girl. The only time I have been quicker through a paddock section has been on the rare occasion that he had dropped it.
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sorry to butt in but I'm looking for a cylinder for a xt/tt 250 do you have one to spare? thanks
bump
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Sorry, No. I might be looking for one myself, as I have just measured the bore on the cylinder that I have and it is 4th OS and the corrosion would require a rebore to remove.
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Beware over revving the TT 350, I held mine flat for too long during the 88 Mallee Rally and I had one of the cam shafts jump a tooth, took me ages to work out why it was running like shit, only worked it out after finding out a mates jumped both cams and his valves did a tap dance on the piston
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"Adam (the guy on the 2 valve) is a good rider and is deceptively fast on the old girl."
Impressive...imagine how fast he would be on a husky! ;)
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Beware over revving the TT 350, I held mine flat for too long during the 88 Mallee Rally and I had one of the cam shafts jump a tooth, took me ages to work out why it was running like shit, only worked it out after finding out a mates jumped both cams and his valves did a tap dance on the piston
Would that be caused by a stretched timing chain or worn adjuster Geoff? Or is it the nature of the beast?
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Another SA rider here i will be building up a tt350 as well over the coming summer have two in my shed 91and 94 have the 86 250 as well but its just a roller so thats the one i will be doing up hope to do a couple of road trials next year on it if all goes to plan cheers jeff
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Sorry, No. I might be looking for one myself, as I have just measured the bore on the cylinder that I have and it is 4th OS and the corrosion would require a rebore to remove.
that's ok ive managed to get a cylinder on standard bore and needs to go to 1st oversize
yep mines on 4th and its worn, but when looking I found the std twin came bore is 73mm
and the std single came bore is 75mm so does anyone know if the single cam piston can go into the twincam if anyone has an old sohc piston I would be interested in it to do a comparison
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Trusting my memory:
The SOHC piston has a big ugly hump in the middle to get the compression ratio up, and is quite different to the twin cam piston.
Pics on parts list may help to confirm or deny this.
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I had no luck finding a high comp piston for my 350. Stock is 9:1. With a few head mods and a 20 thou shave on the head and barrel I've managed to bump compression up to about 9:8. Now I just have to tune the carbies to the head and exhaust..... I hate twin carbies on single cylinder dirt bikes as they need to be removed to make any changes. Even worse that the TT secondary is a vacuum assisted main jet!
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Trusting my memory:
The SOHC piston has a big ugly hump in the middle to get the compression ratio up, and is quite different to the twin cam piston.
Pics on parts list may help to confirm or deny this.
thanks Nathan, will look into it, but would still like to have an old tt/xt single cam piston in my hot little hands please, just thinking Mill !
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Sorry, No. I might be looking for one myself, as I have just measured the bore on the cylinder that I have and it is 4th OS and the corrosion would require a rebore to remove.
that's ok ive managed to get a cylinder on standard bore and needs to go to 1st oversize
yep mines on 4th and its worn, but when looking I found the std twin came bore is 73mm
and the std single came bore is 75mm so does anyone know if the single cam piston can go into the twincam if anyone has an old sohc piston I would be interested in it to do a comparison
The SOHC piston has a higher deck height (distance from piston pin to piston crown) and domed piston crown, and also uses a larger diameter piston pin.
(http://i150.photobucket.com/albums/s120/coljay/XT250%20pistons_zpsbvctyziy.jpg)
SOHC piston on the left, DOHC piston on the right. (SOHC piston also has a large hole in the top due to a dropped valve!)
As the crank in my engine (TT250) was stuffed, I have gotten hold of a XT250 bottom end which is virtually the same (yes, I know some of the gearbox ratios are different) and will be building up this engine with the TT250 head. I was also able to find an XT cylinder that is 0.5mm oversize to replace the rusted 4th over cylinde I have. Pistons in this size (0.5mm OS) are NLA from Yamaha, but I was able to get one from Halpins in QLD.
Frame and assorted parts are in being powder coated and hopefully will be ready next week.
If the Big Race tomorrow turns in to the Boring Race, I might even get the engine together tomorrow.
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Sorry, No. I might be looking for one myself, as I have just measured the bore on the cylinder that I have and it is 4th OS and the corrosion would require a rebore to remove.
that's ok ive managed to get a cylinder on standard bore and needs to go to 1st oversize
yep mines on 4th and its worn, but when looking I found the std twin came bore is 73mm
and the std single came bore is 75mm so does anyone know if the single cam piston can go into the twincam if anyone has an old sohc piston I would be interested in it to do a comparison
thank you for doing that and for the other info as well
The SOHC piston has a higher deck height (distance from piston pin to piston crown) and domed piston crown, and also uses a larger diameter piston pin.
(http://i150.photobucket.com/albums/s120/coljay/XT250%20pistons_zpsbvctyziy.jpg)
SOHC piston on the left, DOHC piston on the right. (SOHC piston also has a large hole in the top due to a dropped valve!)
As the crank in my engine (TT250) was stuffed, I have gotten hold of a XT250 bottom end which is virtually the same (yes, I know some of the gearbox ratios are different) and will be building up this engine with the TT250 head. I was also able to find an XT cylinder that is 0.5mm oversize to replace the rusted 4th over cylinde I have. Pistons in this size (0.5mm OS) are NLA from Yamaha, but I was able to get one from Halpins in QLD.
Frame and assorted parts are in being powder coated and hopefully will be ready next week.
If the Big Race tomorrow turns in to the Boring Race, I might even get the engine together tomorrow.
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If your still going with the TT350 engine i recommend hanging onto the 250 head, the valves are the same size (on the ones i have measured) but the smaller combustion chamber helps lift the compression by a fair bit. You will have to weld up the existing 250 oil gallery between the combustion chamber and the cam chain tunnel and use the 350 external oil line. I have done this mod and it livens the old girl up a bit, no problem with pinging or overheating although i did weld larger fins onto the head (not sure if this helps or not). Pay attention to the squish band when putting it back together as from the factory they can be pretty loose in tolerance here, I ended up dropping off the base gasket and running case sealant to get it about right.
They also run stupid lean on the pilot jet if still on factory jets, jets can be hard to come by in different sizes but i have found that the pilot jet from the XT350 is pretty much bang on. the primary main and secondary main are standard. this is on a bike with larger headers opened up airbox and a staintune exhaust.
Hope that helps
Tom
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Pretty helpful first post Tom 8) kinda makes me want to get a tt350 project ::) ::) ::) ;D
What else are you into in bikes?
And what state are you from?
Welcome aboard.
Cheers,Mick.
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Thanks Mick,
Forgot to mention that the best money is spent on the suspension, had the shock revalved resprung to suit my weight- factor in a re-chrome of the shaft as they all seem to eat themselves. forks much of the same with cartridge emulators. Hands down the best thing done to the bike, very happy to recommend the business that did the shock
From NSW, Maitland area. Also have a 86 kdx200 and and 81 katana1100.
As for a project bike with a few mods they go pretty well, can hold my mates on wr450's in the tight to med scrub, only lose out in the open. And at least i don't have radiators to wreck my day when i bin it
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;D ;D ;D
Great place Maitland, I lived/slept up there on and off for Seven years, country folk are cool.
Just last week a new acquaintance was telling me a similar story about these modern suspension techniques and outcomes on his old Maicos. A brand that had close to the best handling suspension in the day, but made even heaps better by his account?
So starting to accept the reality of these mods, after just reading your account of it too 8)
NEXT: THis is an example of what we call a thread hi-jack ;D ;D ;D
You have well suited bikes there for NSW Vintage Trail Riders club, heaps of fun.
http://forum.ozvmx.com/index.php?topic=37135.0 (http://forum.ozvmx.com/index.php?topic=37135.0)
If you want to feel the buzz in your own back yard?
Great week end coming up on the 5th and 6th November at Cessnock
Drop in for a look :) Cost to you will be nill, unless you choose to purchase from the local clubs Kitchen ;)
(http://i677.photobucket.com/albums/vv132/mc125mick/a88570c1-ea6c-4112-9f97-20e781a7b417_zps8cvgkf7m.png~original)
(http://i677.photobucket.com/albums/vv132/mc125mick/9b7ee711-96a5-4de7-a69a-aa05caae2c68_zpsrqmxn03i.png~original)
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Hey thanks for the excellent write up on the TT mods Tom. I have done similar mods to mine apart from the 250 head. I took 20 thou of the head and barrel to bump up the compression a bit. I figure I have 9.8:1 now which is better than the standard 9:1.
I suspected my TT was (is) running lean. I drilled the original pilot jet and lifted the needle which has made it better but it's far from acceptable for me. What size is the XT pilot jet?
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Yay me jug arrived and yep on std bore and yes will need to go to 1st o/s
thank you for your insight, you have my attention
Oh yer who knows the best place to source the dohc pistons, a bit thin on the ground plus I'm a tight ass
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A bloke I work with has a 1993 ish TT350 which will not start and needs air scoops and side covers (missing somewhere along the line) also has a bunch of older TT350 stuff going with it, mostly frame and susp stuff from what I see.
Any how, he wants to clear space in his shed and has no interest in this bike or parts. I suppose you can buy a going bike most days of the week for around a grundy and he asked me what I thought is was worth as is, maybe half a ton?
If any one reading this thread is inspired to own a TT350 and they want to tinker with it you can send me a pm for Gavins contact details and you might hash out a deal on the TT.
The bike is located in between Ipswich and Toowoomba and would be a pick up arrangement only.
Just putting it out there, the bike is not advertised anywhere and it needs a new home.
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The standard TT350 pilot is a 40 the xt350 pilot is a 42, cannot remember if i reamed it a touch o/size from that. Mucked with the pilot until i had the needle screw 11/2 turns out and it is clean off the bottom. Watch the cam cap retaining threads or better yet replace the bolts with studs as the threads in M6 threads in the head seem to be pretty soft and prone to stripping out. Also keep the automatic de-compressor, as yamaha made the kickstart shaft out a special steel/cheese alloy that is pretty easy to snap the splines off
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Thanks for the advice on mod' ing the 350 engine. At present I have decided to rebuild a 250 engine using a XT bottom end (yes I know the gear ratios are different to the TT) and fit the TT head an carbies.
I have actually gone a bit over the top considering this was supposed to be a quick and dirt rebuild to get a better bike for next years SART series. I have had the frame and ancillary fittings powder coated and all the bolts axles etc re-zinced. Since the frame looks so nice I have lashed out and ordered new front and rear guards as the one I have were going to look tatty along side the new Clark fuel tank that I will be using.
I have just finished a strip and clean of the front forks and am looking at getting the rear shock overhauled. I have struck a minor problem with the forks as I only have a XT manual, and need to know the fork oil capacity / level, also a suggestion of what weight oil is best in the forks as there are std would be helpful.
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Oh yer who knows the best place to source the dohc pistons, a bit thin on the ground plus I'm a tight ass
I got a wiseco from ebay.....you need to search the US ebay site
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a good start point is 150 mm from the top of the tubes with the forks collapsed using 10 wt but im sure someone will pop up with the correct details soon
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I think i will have specs on the fork oil. Will report back in a couple days when i find the book. Also in USA they were called a TT225.
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Oh yer who knows the best place to source the dohc pistons, a bit thin on the ground plus I'm a tight ass
I got a wiseco from ebay.....you need to search the US ebay site
thank you
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For TT350 all models my book (Fast Facts for Yamaha 1995 edition) says 533ml of 10w fork oil. Same specs for the TT250's up to '93 with 41mm forks too.
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Thanks for that. I also found a TT350 owners manual online that said 533cc 10W.
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Well, the comedy of errors that started with me buying a TT250 and not the TT350 that I thought I was buying continues.
Things have progressed well over the past month or so. I have had the frame, hubs etc powder coated and all the spokes, nuts, bolts etc re zinc plated and started putting the chassis back together. I have also been able to build up an engine putting the TT250 cylinder head onto a XT250 bottom end since the crank in the TT was totally stuffed. This weekends jobs were to finish overhauling the front forks, rebuild the wheels and get the chassis up on the wheels and fit the engine.
All went well with the front forks, and lacing and truing the front wheel was fairly straight forward as I was using the original rim and re plated spokes. The rear wheel gave me a few moments, and was just being a pain in the arse trying to lace up. Even though I have rebuild numerous wheels over the years, this was the first with Yamaha's infamous Z spokes. Things just didn't want to go together, I had a nice new Excel rim and was using the original spoke set, freshly re-plated. After a lot of struggling, I decided that something wasn't right. I then counted the number of spokes in the hub. This was the light bulb moment. Yes I was trying to lace my shiny new 36 spoke rim to a 32 spoke hub. Bugger! Bloody Yamaha, and there stupid designs.
Not to worry, god looks down on the idiots of this world with some compassion. On Thursday a mate in Darwin bought a 1991 TT350A for me off of Gumtree for $300 (we are trying to sort out how to get it from Darwin down to me in SA with out spending more than the cost of the bike itself). Anyhow, there was a spare rear wheel with the bike. John is going to remove the tire, check the condition of the rim and if it is OK ship said spare wheel down to me so I can use the rim on the 250.
So a couple of pictures, here is the stating point;
(http://i150.photobucket.com/albums/s120/coljay/TT350%2030-8-16_zpsmzs17umb.jpg)
and here is the bike as it is now.
(http://i150.photobucket.com/albums/s120/coljay/TT250%206%20nov%2016_zpscv8qxzid.jpg)
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Wow thats looking nice so far. I know you can get 32 spoke Excel rims because i did some YZ/TT600 wheels that were 32 spoke. From memory the front Z spoke (85 YZ250) laced up to the rim ok but we had to mod the spoke holes in the rear rim to get the angles right. This was for a sidecar too. I don't know who has trouble with Z spokes/Z spokes hubs breaking but we have never had a problem with either Z spokes breaking or hubs breaking. In the 24hr the odd drive side rear spoke (not a Z spoke) would break which was accepted as the norm (spokes zip tied together so you just keep riding) but that's about it. I thought if they were such a bad design that it surely would have shown up with sidecar use but never did. I think it must be only hard motocross or supercross type jumps that caused failures back in the day and or lack of maintenance? I do know with brand new bikes it takes a while for the spokes to bed in and you need to tighten them up a fair bit initially. I have found this to be the case with any new Australia Post bikes.
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Good work
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Damn that's a great looking bike
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A bit more progress on the TT this weekend. I have had the rebuilt engine running, it was a bit smokey for a while, but after clearing out the oil from assembly and from an over oiled air filter element it settled down and is running nicely and smoke free.
I also finished making the new lighting set, and have also finished my 12V electrics conversion using the XT250T stator windings and rectifier / regulator and a modified std TT wiring harness. I have started to make up a new battery box as I couldn't find a 12V battery small enough to fit into the std battery case. I also haven't fitted the HID gear for the top light, and will probably just run a halogen globe in it for the initial test rides and leave the HID installation until just prior to the start of the 2017 season.
(http://i150.photobucket.com/albums/s120/coljay/TT250%20lights%202_zpsmmnclk1v.jpg)
As it was raining today I got a bit more free shed time and was able to cleanup and polish the very oxidised cooling cowls that fit onto the fuel tank. they are now a reasonable shiny red, and not the dull pink they used to be.
Also, an end is in site for my rear rim dramas. After contacting all of the wreckers that I normally use without any luck, I found a guy on Gumtree in QLD parting out a TT350 and have done a deal on buying a rear wheel. As my luck has it, my younger brother rang to tell me that he was buying up a heap of stuff from a wrecker that had closed up. Yes, he had a TT350 rear wheel in goodish condition, so I now have two complete rear wheels on the way. I suppose that there is no harm in having a pare wheel.
Hopefully the wheels will arrive during the week, and I can steel a bit of time from the house reno to build up the rear wheel and get the bike off of the bench.
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These LED H4's get good reports. Big thread on them at ADV rider forum
http://advrider.com/index.php?threads/new-long-range-led-aux-lights.839163/ probabl want to skip the first 50 or so pages and go to the lastest info though
http://www.cyclopsadventuresports.com/3800-Lumen-H4-LED-Headlight-bulb-_p_83.html
These are good small batteries too. I fit a lot of these to bikes these days
https://shop.antigravitybatteries.com/
look at the small case versions
I have replaced battieres the size of car batteries with these Lithiums which are way lighter and still have enough CCA's for electric starting. No more acid leaks, mount in any position, light as a feather, long life, no maintenance required etc etc
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These LED H4's get good reports. Big thread on them at ADV rider forum
http://advrider.com/index.php?threads/new-long-range-led-aux-lights.839163/ probabl want to skip the first 50 or so pages and go to the lastest info though
http://www.cyclopsadventuresports.com/3800-Lumen-H4-LED-Headlight-bulb-_p_83.html
These are good small batteries too. I fit a lot of these to bikes these days
https://shop.antigravitybatteries.com/
look at the small case versions
I have replaced battieres the size of car batteries with these Lithiums which are way lighter and still have enough CCA's for electric starting. No more acid leaks, mount in any position, light as a feather, long life, no maintenance required etc etc
thanks
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The first of my two "new" rear wheels arrived in the post on Friday. With a bit of effort (plus CRC and heat) I was able to get all the spokes undone and the rim off. On Saturday afternoon I managed to lace the rim to the powered coated hub, true the wheel, fit the new tire and sprocket and have the wheel in the bike in just under 1 hour.
(http://i150.photobucket.com/albums/s120/coljay/TT250%20rear%20wheel_zpsmsqdmfvg.jpg)
I still have a few minor thinks to finish off, the battery box, a new alloy sump guard, applying the rest of the decals and fitting a new front brake disc. But the who can resist the temptation to ride a newly rebuilt bike? So I took the bike off of the bench this morning, fired it up and took it for a quick blast around my block. Oh the joy of living in the country on a few acres, where else can you do a race start at your front gate and be almost fully tapped out in 6th gear before the end of your driveway! Overall I am quite happy with the bike so far, it it has a bit more poke than the old XT250, and handled nicely when I went for a slalom run through the trees in my wood lot. I will have to do something with the rear suspension, its a bit soft for a rider my size, but that can wait until next year.
(http://i150.photobucket.com/albums/s120/coljay/TT250%2011%20dec%202016_zpsyqkgzjhe.jpg)
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great outcome, cant beat living next to a good riding spot for that all important test ride followed by a couple of very cold test beverages
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Another rescued bike....Good stuff!