Chain snap :(

[davidkent]

I see,
I thought it was mixed with other compounds to make the 'casting' as such


I may be wrong however

[Andy FZS]

Looks like a 9 to me I seem to remember the 12 is flush.

[limax2]

Some good photo's there David  .
The hole to hold the oil seal doesn't look too bad to me. The obviously oval part of the casting is just a clearance hole for the push-rod and as long as it is not rubing on the push rod or the bearing inside it doesn't matter what shape it is and will be o.k.
I take it you have not yet tried a new oil seal yet. You might find it is a good fit anyway. But you obviously need to do something about the retaining plate.
I think the main issue with chemical metal is having the parts to be fixed spotlessly clean.
On the subject of welding, is it the oval hole you were thinking of or the recess for the oil seal, approx 22mm dia? If it is that oval hole just leave it for the reason I've just given.
If you are struggling to get the push rod out it is no big deal to get to the other end, but you might need a new gasket for the cover. You just need to take the clutch cover off, then undue the six bolts that hold the clutch pressure plate and remove that plate. The rest of the clutch can stay put. You then lift out a short stepped push rod and catch the 5/16" ball bearing. (Strangley not a metric size). Then you can push the push rod from either side.
If you do it all from the chain side and you are not sure if the ball bearing has dropped out measure the distance from the end of the new push rod to the sprocket cover fitting face. It should be round about 32 to 33mm. If it is 8mm less the ball bearing has gone.
When I mentioned adjusting the clutch cable in a previouse post I should have said it is the adjustment opposite the push rod in the sprocket cover that need some care.
Keep us informed and good luck.

[davidkent]

Limax - You've just made my day.
So potentially, with a new oil seal, it should be  fine?


My concern was that the oil seal used that to seat, but if it uses the larger outer edge to seat, then as you say it shouldn't be a huge problem anyway.


Also helps with the ball bearing - So basically, if i push the new rod on in, as far as it'll go, it should stick out around 32mm, if its closer to the 24-25mm mark with it stationary as it is, then the bearing has gone?


How does the bearing fit? obviously if i don't have to drop the oil and remove the clutch cover, i'd rather not and so this solution makes sense.


I was simply under the impression that the oval hole was what seats the seal and left me basically screwed - the back of the hole still looks round, its actually just the face that seems ovaled.


In short, replace all the clutch rod, seal and so on, stick it back together and it should be fine?

[limax2]

You have got the idea Dave and glad I made your day  .
The ball bearing sits in the bore of the gearbox input shaft between the short push rod, at the clutch end, and the long push rod (245mm long) that you will be replacing. It can't drop out at the clutch end unless you remove the pressure plate and short push rod. It doesn't usually drop out at the sprocket end but it can do, especially with no oil seal there.
There is another ball bearing in the withdrawal mechanism but that is trapped in there so no problem.
If you do have to remove the clutch cover you can put the bike on the side stand and hardly any oil will come out. On the centre stand some might come out but not a lot.

"In short, replace all the clutch rod, seal and so on, stick it back together and it should be fine?" But not forgetting to check and maybe adjust the screw behind the rubber bung in the sprocket cover, especially with having changed the push rod. Details of how to are on this site somewhere I think.

[davidkent]

Right,


Thats all i needed to know then.
Thanks


Now, where can i get all these bits online? it just so happens to be pay day


Also, what are decent brands of Chain and sprockets? and original teeth etc?


Basically I'll need:


Clutch Rod
Clutch Rod oil seal
Ball bearing (Possibly)
Sprockets
Sprocket Nut and Tab Washer
Retaining plate for clutch rod oil seal (Assuming thats the bracket i've mullered near the sprocket?)
Chain


and is there a gasket for the sprocket cover?


Cheers

[fazersharp]

His ball bearing should still be in there because the rod has snaped where it turns to alluminium and is still in there as far as I know.

Dave can you post a picture of the bit of the pushrod that you do have

[davidkent]

I have 2 small bits of Solid pushrod, the bulk is still in there nicely


Will get a pic shortly

[fazersharp]

If you look at my picture you can just about see the retaining plate/tab, yours has bent down, you dont need a gasket for the sprocket cover ---- is the gereral consensus on this forum

[davidkent]

Yeah wondered what that was for lol
Sounds good - Now its just finding an online supplier and the bits - Then a half sensible chain and sprocket set


Cheers

[limax2]

When you order the sprocket nut and lock-washer make sure you ask for part number 90891-10124. That is a kit of both the 12mm nut and lock-washer. Some Yamaha dealers will still look up the old 9mm nut and supply it.
Any Yamaha dealer should be able to order them. I've never done it on-line myself but Fowlers of Bristol and Wemoto are a couple that seem to get good reports. There are others.
Standard sprocket teeth are 15 front and 48 rear. Any well known brand of chain like D.I.D. and EK should be o.k. but I would avoid cheaper less known brands.

[davidkent]

Sounds good, will look for that part number specifically
I had thought D.I.D were a reasonable brand so will probably go with them also.


Thanks

[davidkent]

Back to an old thread - I've sorn'd the bike for the time being, with this weather and all that...


BUT, i do have lots of shiny parts sat here waiting to do the job - Just thought i'd get back on here

[69oldskool]

What was your experience with chemical metal? It would be interesting to hear, as a number of people have considered it for various fixes, but I've yet to see anything definitive on the subject. I would've thought it'd be ok in this instance, as the application area shouldn't need to take much stress of any kind?

JB weld's the one to use.
Takes like forever to cure, but good stuff once set & temperature resistant.
Excellent for filling in gouges in alternator covers prior to respray for instance. :o 

http://www.jbweld.com/product/j-b-weld/

[davidkent]

Sounds good to be fair, though i think i've cracked this problem with another method - Will soon see i guess.


Cannot wait to get the bike sorted, but unfortunately the MOT ran out last week, i thought it was April - I was wrong.


Have to get fixed then find a decent tester around here - Never MOT'd a bike before!