Chaincase bolt

[MAMILLA]

I pulled my chaincase off today to gear it down because of the change to 162" and the bolt that holds the bottom sprocket was broken i dont know if my friend tightned it to much or what but can i get that bolt from any hardware store?

 

[Nikolai]

Let me guess, you have reverse?

 

[BBNytro]

yeah should be able to find it at any bolt supplier. Can't remember what size it is?!?

 

[MAMILLA]

Let me guess, you have reverse?

Has something like this happened often or do you think i over tighned it

 

[Nikolai]

Seems to happen to anyone with reverse.

 

[Mtnviper]

Has something like this happened often or do you think i over tighned it

I have a theory on this. Did you torque down the bolt, before tightening down the two set screws on the bearing at the clutch side of the drive axle?
Reason I ask, is because the bolt not only holds gear on, but positions the drive axle to the chain case. If the left hand side bearing set screws are tightened down first, it could hold the axle over to the left slightly causing an increased side load to be put on the bolt when its torqued down.
If that makes sense?!
Anyway I usually torque the bolt down, then rotate the axle a couple times by turning the track. To allow the left side bearing to position itself on the axle, then tighten down the set screws. Just in case it makes a difference!

 

[MAMILLA]

Has something like this happened often or do you think i over tighned it

I have a theory on this. Did you torque down the bolt, before tightening down the two set screws on the bearing at the clutch side of the drive axle?
Reason I ask, is because the bolt not only holds gear on, but positions the drive axle to the chain case. If the left hand side bearing set screws are tightened down first, it could hold the axle over to the left slightly causing an increased side load to be put on the bolt when its torqued down.
If that makes sense?!
Anyway I usually torque the bolt down, then rotate the axle a couple times by turning the track. To allow the left side bearing to position itself on the axle, then tighten down the set screws. Just in case it makes a difference!

I tightened the set screws first so i will loosen them and tightened the nut fist.

 

[northerndoc]

Don't think you did anything wrong. Mine was broken straight from the factory. First time I had my chaincase apart was at 500 mi to switch tracks and when I opened the case, the bolt was snapped. Supposedly the '08s had the same problem, so Yamaha designed a stronger bolt and installed it in the '09s. Obviously this didn't work either. You aren't the first one to have this happen. Your dealer should get you a new bolt for free, but I just took the remnants of the broken one and went to the hardware and found one that would work. Never got around to installing the replacement from my dealer.

 

[skidooboy]

i have 2 08's with reverse, i have had my chain case apart 3 times, and my wifes sled once. niether sled has broken the bolt in question. i have the updated bolt here @ house, in case i ever have the problem.

only one of the 4 times total these sleds have been apart have i messed with the set screws or clutch side bearing. and that happend to be just today when i reinstalled the drive shaft with my new avid drivers. i realined the brg and set screws to the marks from the original factory install, and tightened them down prior to installing the shaft in the sled.

guess i'll find out if i have a problem if and when i take it apart again. the above theory appears sound, i am just stating i have done it the opposite way and not had a broken bolt issue 3 times so far.

i am wondering if people are over torquing the bolt. the manual only says to torque it to 40 foot pounds. and i make sure i torque it only to factory specs.

it is nice to have a forum like this to work together to make a better mouse trap, and help one another through issues. ski

 

[mmaxcarver]

Mine was fine when I pulled the chaincase cover off the other night, I have reverse and my drive train is still stock.