125H runs for 5 minutes then dies

[BONEHEAD]

um you rode the bike with out any sought of cooling ? and a loose bolt caused the wear on the clutch drum? are you serious? was this whole post a HOAX did you have this so called brain wave before or after you decided to create this ,i ask you  would you drain the coolant from your car and drive it? NO NO NO ,so now tell me has the bike now had top end re build such as new piston and bore,,and i trust mister yamaha has assembled the bottom end correctly , i know this is a learnig curve but you must know the basics before even touching a spanner,GOODLUCK WITH THE 250

[YZ250H]

No no no - I'm not THAT stupid.   I only ran it for about 2 minutes - not even long enough for the head to get slightly warm - I only did this twice - sorry, enthusiasm got the better of me    it was the first day I got it home and I HAD to see if it went.  The very next week-end on went the water pump cover (and coolant).
Of course the post insn't a hoax, why would I do that
The bolt in the clutch was nothing to do with this thread - it's a long long time ago - I think before you even came on here.  There was a bolt that wasn't required that rattled loose and jammed in the gears (from the previous person) siezing the bike (others would remember).

Bike came with new piston and rings installed.
I will take your comments re touching spanners on board.
There is no water anywhere to be seen on the 250 - thank god

[BONEHEAD]

mmm, enthusiasm can be the enemy,it can cause kaos in every part of life, i may have been over enthusiastic myself on the odd ocassion,anyway any news on the bottom end im still keen to see this bike run i wish to retract my entusiastic comments as i understand that this is a learning curve, i will still help with any concerns that arise on any of your projects.   cheers BONEHEAD
ps got the seat back for the 250g looks fantastic.

[YZ250H]

Took the clutch cover in to Mr Yamaha yesterday - he's going to replace the seal for me on the impellor, check the shaft for wear and replace the seal on the gear shift shaft.
He's resealing the cases with the good stuff (I'll find out what it is and tell everyone - no good keeping it a secret) and replacing the crank seals.
Right from the start I had reservations about the 125H being water cooled - now I've got 2 of the little buggers.  Should have made them 125 G's instead 
Boney, I would and do appreciate your help with this stuff (as with others).  You never know - one day I might have learnt enough from you blokes to help someone else .  I know I have a long way to go .
Photos of the seat installed please - where did the cover come from - I've heard mixed stories about different suppliers of them too.  The pipe looks great - I was going to steer clear of them 'cause XYZ had a bad communication wrap, but if Les does the hard yards for you then I might reconsider.
I deserved a bollocking for running it without coolant as it was pretty dopey   .  Lesson learnt.  Enthusiasm is sometimes misplaced .
Cheers   

[DJRacing]

The sealant they use is Yamabond 5, it is a grey looking sealant used for bonding engine cases together.

[BONEHEAD]

sooooooo! did you get it running yet or is there still a concern

[YZ250H]

I was wondering how long it would be 'till someone was on my case .  I thought everyone had got the sh1ts with this thread and forgotten about it.  Lord knows it has been going long enough.  I think I am even getting bored with it 
So Mr Yamaha has let me down once again.  I guess if you lived in FNQ you would understand.  One of the best things about living here is the relaxed lifestyle.  One of the worst things about living here is also the relaxed lifestyle.  It doesn't matter if it has to come from Perth or next door it's going to take 2 weeks.  Even in Maccas you usually have to wait for a burger.
Sooo sorry folks it's going to be next week.  Hopefully Hilly will still have enough facilties left to be able to run the video.  I know he grows older by the minute.  I'd have to say I was VERY impressed by his holeshot on his  first day back racing after 25 years.  Well done son 

[Hoony]

yeah, you should have seen the grin on his face that day, longer than the Newell Hwy 

[YZ250H]

I reckon he deserved that grin Hoony.  I would be well chuffed if I had achieved the same.  I watched his video the kids made and apart from the great shots of the shitty weather (sky) you have down there they got some beauties of Dad bolting out of the gates then letting everyone go past  .  The commentry was just great.  As I said to Hilly at least you can count on your kids to stick up for you.   I have never met Hilly, but can't wait to.  We've had a few good conversations on the phone and he has picked up a bike for me.  Nothing beats talking over a beer.  I'm coming down for the superbikes next year, so maybe we could make an event of it   

[BONEHEAD]

soooo! any news on that 125 of yours its rather quiet , cant here it running yet.

[YZ250H]

This week-end.  FINALLY got the bits back from Mr Yamaha.  At the last minute he checked the shaft on the impellor ($69) and it was worn too.  "That'll be another 2 weeks mate"   Kicking myself now that I didn't buy one of those on Ebay a little while ago.  I wonder who bought them  . 
Monday for the video - If I can work out how to download.  Otherwise photos.

[YZ250H]

So an update...  Went and picked up the motor this afternoon.  It was all good until I looked at the bill....$530  .  I was a little shocked to say the least.  $180 for parts and $350 for labour.  Sooo from now on I will have to do things myself (with your help of course).  I'm a bit cranky 'cause that $350 could have gone into a resto .  Apparently the bike has just doubled in value (or at least the amount ot owes me has!!)
Anyway enough bitching.. on with the story.
Problems encountered - Crank has turned in Main bearing on rotor side, Primary drive key was missing  (Item 17 on the cranshaft diagram for those with a parts book - thanks DJ ) I could be wrong, but i think that will explain the teeth marks in the clutch basket.
New water pump seal and impellor also fitted.  Hopefully I will be able to have $500 bucks worth of fun on her this week-end to set my mind at ease  .
At least we have progress.
While I was at Mr Yamaha he mentioned he had all this old NOS yamaha stuff out the back and he is retiring 21 December.  I put him onto zedder so he could find what bikes the bits come from.  He gave me first option on the bits when he gets the list together.  Must have been the shocked look on my face when I read the bill  maybe he felt sorry for me.
So let me get the list and I'll see if there is anything useful on it.  Anything i don't take will go on eBay.  I'd rather give the good blokes on here a chop at the bits first.  A few things he mentioned was NOS side cover for DT360A and some NOS barrels of unknown origin.  I'll keep you posted.
YZ video coming to this channel soon.  Stay tuned

[YZ250H]

She's back together.  It started and ran OK.  Still a bit dodgy though.  Have good circulation through the radiator that it didn't have before.  Steering head now bypassed.
I couldn't ride it yesterday cause I broke the clip on the joiner link on the chain .  I think I've got a spare hanging around somewhere .
Pulled the carby apart again to check out the jet sizes.  Found jet needle to be 6F16 (on the middle groove).  Going by the manual it is supposed to be 6F21.  Geez it shits me when people screw around with things.  Can't tell what sizes the main and pilot jets are as I can't see anything written on them (even with my glasses on).  I'm guessing this is part of the problem.  Looks like a complete new set of jets, so I can be sure they are the right ones.
Hopefully I can fnd that other spare link and should be able to get that video for Hilly .
Down to the small stuff now.  Looks like I just have to work on the jetting and it will all be good.

[DJRacing]

This is all sounding good 250H, yeah change that needle, the 16 is quite different to the 21. The 16 will make it run very rich threw quarter to half throttle. And look at the neddle jet(the brass piece the neddle goes in), that can wear oval, so its a item you might want to renew.
Good luck and keep the info coming.

[YZ250H]

I reckon you are bang on DJ.  Just came in from riding around.  Took some photos, but we have some "technical issues" on the video.  I will post photos tomorrow.  Went through 2 litres of fuel in 2 sessions.  No sign of dying    Once on the pipe she goes very well - does that mean the main jet is OK ?  I think as you suggested ages ago the pilot jet is too small as she will only push start with the choke on.  I had to push start my old GSXR1100 a few times, so a 125 is dead easy  .
Anyway at least I can ride around and have some fun on her.  I'll get the proper jets and maybe chuck the boost bottle and she should be sorted.  Now to work on those brakes and suspension  .
Thanks everyone for all your help on this one.  Photos tomorrow and video some time after that.
It's almost time to put this thread to bed