Author Topic: 1979 YZ80F (Read 8590 times)

alexbrown64 · « **on:** May 18, 2018, 10:23:24 PM »

Hi gang,

I have added a new bike to the stable. A 1979 YZ80F. Had one new back in the day. Had a good season on it, as it was a rock solid mini racer.
Anyway, i have started collecting parts and am stuck for a filter cage. I believe the filter cage is the same for the E, F and G. Part number 2J5-14458. I have searched all my regular hunting grounds and i have hit a dead end.
Anybody have a spare tucked away? Pic below of the cages was grabbed from Facebook...

The idea is to get her ready for the boy to ride (with the XR75) in some VMX meetings just for a bit of fun... then do a full rebuild later on.

Will add progress reports..

If anyone has any other nos parts they want to sell, i would be very interested. Especially plastics..

Cheers,

skypig · « **Reply #1 on:** May 18, 2018, 11:30:38 PM »

Can’t help you with parts.

I also has one new in 1979. Won the A grade club championship on it.
(Got beat by the fast guys on their YZ80E’s the year before, when I was YZ80D mounted. Big advancements each year in those days.)

Slakewell · « **Reply #2 on:** May 19, 2018, 08:32:14 AM »

The F was a big step back in the day for 80's was it the first 6 speed?
You could get a metal fab guy to make one from 5mm 316 stainless bar?

skypig · « **Reply #3 on:** May 19, 2018, 08:48:26 AM »

Can’t remember if it was the first 6 speed, but it was the first with an internal rotor ignition. The far less “flywheel” made for a free/faster reving, more “modern” engine. They put a brace on each side of the swingarm as well. The single brace on the E was far less strong.

Iain Cameron · « **Reply #4 on:** May 20, 2018, 10:25:34 AM »

I might just have one , well I know I had one at this years BBB . get back to you once ive checked the shed . Iain

alexbrown64 · « **Reply #5 on:** May 20, 2018, 06:33:58 PM »

Thanks for all the input guys..
If you don't have one Iain, then i will have to make a temporary one out of SS tig wire and tig it together. Will be strong and lightweight. But i do want an original for the future restore.

Pic below of me on the F at the first round of the WA state titles.. I had an aftermarket 17" front wheel..

More stuff to come..

Cheers,

alexbrown64 · « **Reply #6 on:** June 14, 2018, 11:03:46 PM »

Bikes arrived...

I had already ordered a shit load of nos parts and various other items to compliment the bikes.. but when i looked closely.... im going to need a shit load more parts....

The F is OK. Its nearly 40 years old, and its showing every year of its age. Its flogged!!
The airbox is completely missing. The oem plastics are beyond tired..Tyres are flogged, spokes,exhaust, everything.
The good news is the chrome on the forks is good. The rims are OK, Tank only has a small ding, bars only bent, etc..

I have a new front plate, new exhaust coming, new decals, new left number plate, all new hardware, new grips, levers, throttle, cables, etc..

Bad news is i have to find a 2X6 airbox, some plastics and hope the motor, tranny and clutch is OK.

Here is the pipe and some other goodies that are here, or on the way..

Muffler has been tacked to pipe because they lost the clamp. But the pipe is a 2X6 (1979) pipe and muffler, and its all in really good nick..

I was hoping to get the bike ready for my boy to ride, but she is in really poor condition. Perhaps in the next 6 months i will get her into a ride ready bike for some vmx fun days.. then down the track she will get her 40th birthday..

As part of her birthday,.. i mangaged to find a NOS seat cover for only 45 Euros. She also has new seat foam coming, a nos side cover, new Takasago nos rim, and a host of other goodies..

alexbrown64 · « **Reply #7 on:** June 16, 2018, 12:30:56 PM »

The parts list is growing...

Luckily, the fork tubes are clean on the F, so i dont have to rechrome them. The tank is going to need some dents pulled, and then panel and paint.

New old stock left side number plate panel from the U.S

New old stock right side panel from Australia..

New intermediate left engine case cover from France..

New engine kill switch, throttle housing.. slightly different to the E style..

I got a new muffler and exhaust from America. Unfortunately, the muffler is tacked to the pipe. But its all in great condition and with some careful grinding, i can make it all like new.

There were a few other parts missing like the airbox, airbox boot, filter cage and filter.. but i have found replacements.
Looking forward to stripping it all down and getting it cleaned up.

Iain Cameron · « **Reply #8 on:** June 17, 2018, 12:39:22 AM »

Sorry Alex Its not there anymore I must have sold it at Broadford .

alexbrown64 · « **Reply #9 on:** June 17, 2018, 08:18:57 AM »

Thats OK Iain, i was browsing around the net and found another a few days ago.
I saw a pic of something i needed.. and then the guy said he had a uni filter he would chuck in for free. I asked him if he had a cage, and low and behold, it was in the filter!! So he chucked in both for free with another order.

The motor is supposed to be on the original standard bore.. we shall see. Looks a bit rough, but its all there... except the airbox and its accessories. I was wondering why the side cover was cable tied.. Its because there is no airbox behind it.

Anyway, a bit of debate going on at the moment. I have my E manual, but not my F manual yet. CSMNL and Partzilla list the part number for the airbox differently for the E as for the F/G. They use the same picture for the E,F, but the F part number is 2x6. The E airbox is 2J5. Some say they are the same..but a close look at the pics shows that they flipped the triangle airfilter upside down for some reason. All the alignment holes and everything else fits for the side covers, airboot etc.. on all 3 models.

2J5 E airbox..

2X6 F/G airbox

Strange one.. i guess i will find out when i get my F manual, as they usually show a pic of the airfilter arrangement.

Cheers,

Cheers,

80-85 husky · « **Reply #10 on:** June 17, 2018, 09:54:33 AM »

with no filter, it will be interesting to see whats inside

OverTheHill · « **Reply #11 on:** June 17, 2018, 11:13:49 AM »

Had one new for the kids or the eldest one [now touching 49 lol] Think it was the F but maybe the G that we were sent a frame gusseting kit that we had to weld in straight out of the crate before bike left the shop. Can't quite remember where but i think part of it was where the subframe support joins down by the swing/arm pivot point. Someone will remember [if old enough lol]. Was quite a few little gussets to weld in i think. Looking at the parts drawing reminds me the reed block is the same as my RT2-360, maybe has a sharpened dividing bar inside for better gas flow out through the reeds but same unit realy. Put boyesen reeds in ours & ran it on alky but half way through the day i had to turn them over as curled their toes up due to the fuel. Might be getting my wires crossed & could all be the G in 1980 but had both. Then the H model changed everything--was an even faster rocket.

alexbrown64 · « **Reply #12 on:** June 17, 2018, 01:59:07 PM »

Quote from: 80-85 husky on June 17, 2018, 09:54:33 AM

with no filter, it will be interesting to see whats inside

Yes.. i am thinking the same thing. Will have to take a peek inside soon. I think it has only been run up the street in the last few years i think, so hopefully all OK. Bike needs A LOT of work.

alexbrown64 · « **Reply #13 on:** June 17, 2018, 02:16:20 PM »

Quote from: OverTheHill on June 17, 2018, 11:13:49 AM

Had one new for the kids or the eldest one [now touching 49 lol] Think it was the F but maybe the G that we were sent a frame gusseting kit that we had to weld in straight out of the crate before bike left the shop. Can't quite remember where but i think part of it was where the subframe support joins down by the swing/arm pivot point. Someone will remember [if old enough lol]. Was quite a few little gussets to weld in i think. Looking at the parts drawing reminds me the reed block is the same as my RT2-360, maybe has a sharpened dividing bar inside for better gas flow out through the reeds but same unit realy. Put boyesen reeds in ours & ran it on alky but half way through the day i had to turn them over as curled their toes up due to the fuel. Might be getting my wires crossed & could all be the G in 1980 but had both. Then the H model changed everything--was an even faster rocket.

Hey OverTheHill, it was the 78 YZ80E that had the gusset kit, as the frames were like cheese. I have the other thread going with that bike. I have a NOS gusset kit that i am going to tig in on that bike, as well as some frame repairs.
Here is a pic of the kit to help you jog your memory....

I also pulled the monoshock on the F this morning while the kids were asleep. It was a fight to the death, as the bolt through the swingarm to monoshock was seized in and i dont think had been removed in 38 years. Lots of work and it came out, but destroyed the pin.
The shock is in great condition. Lots of damping and not much corrosion. They were anodized in that mottle dark green that some of the Yamaha bolts and foot brake levers came in.
I took the spring off and took a picture of the KYB decal and its serial number. I sent it to Tim Lee in Canada who is on Facebook, and he is going to reproduce it exactly with my 2X6-00 preface and my shocks serial number.

The chrome shaft on the F is good, and the fork chrome is good too... so it will just be seals in the forks and some fresh oil..

Cheers,

alexbrown64 · « **Reply #14 on:** June 26, 2018, 11:07:03 PM »

I get my YZ80F workshop manual, but its not a workshop manual. Its a guide that mostly shows the difference between the E and the F. Its interesting because many believe that the E and F parts are the same. Reading this book shows that almost all parts on the two bikes are different.

The airboxes are indeed different...

The cylinders and cylinder heads are also different..

Other things that are different are the exhaust pipes, tank mount, seat base, right side engine cover, ignition, bars, levers, transmission, frame pegs, brake lever, front wheel (F has larger spokes), swingarm, swingarm seal guard, front and rear suspension (forks go from 27mm to 30mm), rear mudguard, throttle.

So, as i am rebuilding both models, and they look pretty much the same, Yamaha totally revised the model and not much really is compatible between the two models.

Cheers,

rocketfrog · « **Reply #15 on:** July 06, 2018, 12:53:16 PM »

There you go, every days a school day! I always thought that the airboxes where the same part, usually a change in number equates to a change in design and there it is. This post makes me feel like resurrecting my YZ80E project. I put it on the back burner ages ago and migrated to other projects. Not before amassing a heap of bits and scouring every source I could think of for the elusive airbox. I think I am going to fabricate one from aluminium, it will go with the translucent side panels and DG arm and head to give it a works mini flavour. Doing a concourse resto on a YZ80 from this era seems like an expensive exercise. I do like the stock look, but the late 70s YZ80 hot rod up real nice.

80-85 husky · « **Reply #16 on:** July 07, 2018, 09:14:29 AM »

go the custom look...get a pipe man to make a trick cone pipe and drill & fabricate to your hearts content

rocketfrog · « **Reply #17 on:** July 08, 2018, 12:46:05 PM »

I have an old school nos PK Racing pipe with a sort of built in silencer so the tip is about the size of a red bull can which looks like a the pipe has no stinger and silencer like a traditional set up. It has a heat shield with holes and PK stamped into it. Fitted, it looks like a shot gun barrel exiting just in line with the cut-out in the side cover.

I have seen these minis accessorised with aftermarket bling to the hilt and they look great. I have a DG arm which looks cool, but there is a company which made a an alum arm out of aerotube (California based - something like CRP?) which looks very unique and trick.

Moto-Tek ignition set ups, Luft shocky with remote reservior and a whole gamit of bolt on goodies could be had for this era of mini. If Shinobi made a water cooled head kit for the YZ80's, I would like to fashion a Mini version of Hannahs' 0W27 with white guards, translucent plates and yellow tank with black speed block graphic - and of course the radiator mounted up front like the J's had.

I sent DC Plastics a seat foam to copy about 18 months ago and now you can get a replica foam for the YZ80E plus there are a lot of aftermarket bits still around for them so building up a respectable YZ80E rodder is probably easier and cheaper than trying to go for concourse.

alexbrown64 · « **Reply #18 on:** July 08, 2018, 06:25:56 PM »

Yep Husky/Rocket, I think the E/F can look and run great as those DG package racers. I guy called Ron Boucher (I think) on Facebook and Vitalmx sells hop up parts for them.
My E and F are going back to original....not concourse, but clean.

Thanks for getting the seat foam set up through DC Rocket. I bought two. The E/F have the same shape on top, but the seat bases were slightly differently molded, but will fit both bikes.
I have a nos F seat cover to go on. The E seat cover is new replica from Canada. It has the piping like the original. The Thai ones don't have the piping.

The problem with the E was the cheesy frame. I have the Yamaha gusset kit I will TIG on. I will take pics of the frame restore. One rare item I found was the wire looking front brake cable guide. Also, I found nos front number plate wire mounting hooks and rubber band..

I think the E is a great bike to do up as a project. You should get yours up and started Rocket, as a DG racer would be worth a lot of money, and look great. I would love to see some pics of that.

My collection of parts is almost complete for the E, except for plastics. I may take my 125G, 80E and 80F hardware to the zincers to get done as a batch. Then take all the frames, hubs, motors etc to the powder coaters to get done as a batch.

Cheers,

rocketfrog · « **Reply #19 on:** July 09, 2018, 11:09:10 AM »

Yeah, Rob Boucher was advertising for parts wanted on the Marks Swap Site. I contacted him a while ago to see if he was interested in the DG parts and he sort of went cold, I think he might have suspected a scam or something - it happens and once you get burned you are shy of getting done again. So I decided to sit on it for a while and see if I get the urge to build it up, I bought it sight unseen from a seller on Gumtree claiming it was a 1980 G model - which is what I wanted. When I got stuck with it I asked if there was any interest in a trade for a G model but no luck there either. So now I have the cheesy framed E which has had the Gusset kit installed previously and a bunch of aftermarket goodies, still not the G but I am somewhat inspired to build it up as a DG Racer. The cool aero tube swing arms were made by a company called CRF - Crotch Rocket Factory. I found a DG inlet manifold New in original package for $20! So there are still good bits around for the model at a reasonable price, I would like to find some period alloy rims for it. The tough one to get will be the 16 inch front in Aluminium, plenty of 17 inch around.

alexbrown64 · « **Reply #20 on:** January 07, 2019, 08:00:45 PM »

I am still collecting parts for this old girl too.

Here are some pics from a Swedish brochure i picked up of the 79 YZ80..

Scored a nice rear mudguard the other day.. almost had to take out a second mortgage..

Also found a nos front number plate too. Just need the white front guard.

Cheers,