YZ450f 2010->2016 connection rod part #

Might want a few bits depending on condition.

Might want a few bits depending on condition.

Pm me what you want

Snagged an engine for $500 off craigslist today! Stokedddd

Edited by JS264

Nice!  So not parting out then I take it?

I'll part out what's left of the engine but otherwise I'm putting it together. I'll be set with the 450 and the 250

Thanks for all the posts on the subject.

 

I'm new to the Yamaha brand, but believed in the myth that the Yamaha was a bulletproof and reliable bike. However either I've been unlucky to get a bike which is not per. Yamaha's normal quality or the been bulletproof is a myth. I purchased the bike second hand, it had 40 hours on it. I was planning to replace the piston only and it was good to go for another 40-50 hours of riding. When I took off the ignition cover I was stonned to see grooves in the flywheel from contact with the stator.My initial through was that the run-out on the crank flywheel side was out of spec. I could feel a little axial play in bearings on the flywheel side, so I decide to take the engine apart and inspect the crank. When I got crank out I found a dent in one of the crank webs. The crank must have been drop on the floor by Yamaha during assembly. I checked the run-out on the crank, on flywheel side it was nearly 0.1 mm and on drive side 0.08 mm TIR (spec. is maximum 0.05 mm TIR). But this could not be the cause of the grooves in the flywheel because the clearence between stator and flywheel is nearly  1mm. However what I found to be the cause of the grooves was when Yamaha pressed the thin aluminium ring in that hold the magnets in place, the ring wobbled and caused waves larger than 1 mm. It could be from thickness variation of magnets not been even causing more fiction during press in of aluminium ring on some of the magnet.

 

In the case of the crankshaft and flywheel, they should never have been put in the engine by Yamaha - they should have been scapped !

 

I'm sure I'm the first one to open the engine after it left the Yamaha assembly plant, because the sealing on the cases looked factory applied and I got the complete unopened OEM gasket kit with the bike from the former owner.

 

On top of this there still the uncertainty regarding the durability of the Yamaha OEM connection rod to be addressed.

 

So now I have to replace the crank, the flywheel and the planned piston replacement.

 

I'm still considering whether the believe I can receive a OEM crank from Yamaha that will not fail or use a Hot Rod crank instead - maybe someone could give advice on this decision.

 

As for the axial play in the bearings I took out of the engine, these were not out of spec. - I purchased a new set af bearings and they similar axial play. It must be due to the clearance class of the bearing, that give the large axial play.

Thanks for all the posts on the subject.

I'm new to the Yamaha brand, but believed in the myth that the Yamaha was a bulletproof and reliable bike. However either I've been unlucky to get a bike which is not per. Yamaha's normal quality or the been bulletproof is a myth. I purchased the bike second hand, it had 40 hours on it. I was planning to replace the piston only and it was good to go for another 40-50 hours of riding. When I took off the ignition cover I was stonned to see grooves in the flywheel from contact with the stator.My initial through was that the run-out on the crank flywheel side was out of spec. I could feel a little axial play in bearings on the flywheel side, so I decide to take the engine apart and inspect the crank. When I got crank out I found a dent in one of the crank webs. The crank must have been drop on the floor by Yamaha during assembly. I checked the run-out on the crank, on flywheel side it was nearly 0.1 mm and on drive side 0.08 mm TIR (spec. is maximum 0.05 mm TIR). But this could not be the cause of the grooves in the flywheel because the clearence between stator and flywheel is nearly 1mm. However what I found to be the cause of the grooves was when Yamaha pressed the thin aluminium ring in that hold the magnets in place, the ring wobbled and caused waves larger than 1 mm. It could be from thickness variation of magnets not been even causing more fiction during press in of aluminium ring on some of the magnet.

In the case of the crankshaft and flywheel, they should never have been put in the engine by Yamaha - they should have been scapped !

I'm sure I'm the first one to open the engine after it left the Yamaha assembly plant, because the sealing on the cases looked factory applied and I got the complete unopened OEM gasket kit with the bike from the former owner.

On top of this there still the uncertainty regarding the durability of the Yamaha OEM connection rod to be addressed.

So now I have to replace the crank, the flywheel and the planned piston replacement.

I'm still considering whether the believe I can receive a OEM crank from Yamaha that will not fail or use a Hot Rod crank instead - maybe someone could give advice on this decision.

As for the axial play in the bearings I took out of the engine, these were not out of spec. - I purchased a new set af bearings and they similar axial play. It must be due to the clearance class of the bearing, that give the large axial play.

could be rare enough to not worry about the odds, but a few people have chimed in that it's a known issue....hate to not say oem, but I'd go hot rods.

OEM is all I would use. You didn't state the year model, but if it's a '14, order the crank for a '15 or '16. 

 

Your experience was not the norm.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now