[amyscich]

While rebuilding the top end I found some galling on the OEM rod and OEM wrist pin. See attached pics. The lower rod bearing has zero up/down play and spins freely. Would rather not split the cases if I don’t have to.


The bike is a 2006. I bought it used in 09. It looked like it had only been ridden a handful of times. I had the oil upgrade done to it shortly after purchase, replace the oil after every 25 hours, and use Mobil1 10W-40 4T motorcycle oil. I mainly trail ride. I have put about 150 hours on it.

 

[shaftman_05]

Mine had that last rebuild. Light smoothing of the rough edges on the rod. I didn't want to sand anythibg away except the raised burrs. Slid new pin in and was like butter with no slop or movement. Ran it all summer no issues. Ran it hard too.

Seen a thread a while back about replacing that bushing, have no experience myself of whether it can be done in the machine or not.

 

[standard81]

I personally wouldn't run that rod. With light use, it may never fail, but there's always a chance. Just my opinion. If you don't have the means to replace the crank, then you may be able to run it as is, but... in my opinion, it should be replaced.

 

[Ononewheel]

Id also recomend replacing if you dont i may cost you double in the end!

 

[standard81]

^^^Precisely. If the rod galls any more than it already has, the pin can seize in the rod, which can cause increased friction between the pin and the piston, which in turn can seize the pin there as well. If the pin seizes both in the rod and the piston, this can cause a lot of collateral damage. The piston can rock in the bore and take out the crank, cylinder, and head. The cases can easily be damaged my all the shrapnel created from the broken piston. Not trying to be dramatic, just putting it out there.

 

[Brady354]

25 hours is way to log between oil changes. i change every 10 with amsoil.

 

[amyscich]

Mine had that last rebuild. Light smoothing of the rough edges on the rod. I didn't want to sand anythibg away except the raised burrs. Slid new pin in and was like butter with no slop or movement. Ran it all summer no issues. Ran it hard too.

Seen a thread a while back about replacing that bushing, have no experience myself of whether it can be done in the machine or not.

thx Shaftman...can you give me some detail on how you went about removing the burrs?

 

[shaftman_05]

thx Shaftman...can you give me some detail on how you went about removing the burrs?

Very fine emery cloth. Patience. I Went for a shiny finish. Best would be replacement as stated, but if you can get it cleaned up it will be fine as long as there are no deep gouges left behind and you use a new wrist pin.

 

[cheetah]

I really think I would replace that crank.