Hello,

last weekend was a nightmare for me.Went to a race track, and in about 10 laps of riding I suddenly heard strange noise from engine. Noise was only heard ,when i shut off the throttle before corner and when i was again on the throttlle then it started to make some strange mehanical noise.

As I didnt want to ride anymore, I went out.Next day I delivered bike to my service, and guys checked the noise, and all said that probablly problem is in conrod bearings.

They took the engine out, and open the motor.And there it was, seized conrod bearing on cylinder 1. Bearing was smashed, also the conrod has markings from bearing. Another story is the crankshaft. As bearing seized, now 1/4 of the shaft where the bearing sits is slightly damaged.

Oil was changed before race meeting, and I always take care and maintaned my bike. Motor has 50000 km, 10000 of that on track.


Anyone expirienced the same problems?


Now what to do? New parts are approx 250 dollars without crankshaft ( this is ok with me), but crankshaft alone is 1200 dollars here in Slovenia.

Can someone check how much it cost in USA? Or if anybody know how we could save or repair the crank?

Best regards,

Bizi

get a used crank off of someone here or ebay for like 50-100 bucks. Maybe you can get one from someone in the EU. then rebuild that sucker and ride.

new crank from Yamaha was $350 last time I checked. pretty common failure for those bikes when they are ridden hard. I have done that same thing to two of my motors so far.