Hey guys. I just bought a 2004 yamaha bruin 350 and the rear end doesnt pull. I can put it in 4x4 and the front end will pull and i can ride it. It doesnt make any noises at all. I was figuring it was the spider gear or the chunk but there are no shavings or anything in the diff. i havent tore it down yet to check it out. Any ideas where i should start?

 

Does the rear propeller shaft turn when moving? That would tell you whether trans or diff issue

 

i have not checked. Ive had no idea where to start. I will check that out

 

Jack the rear end off the ground. Remove the diff filler plug. Put in 4WD, engine off. Turn the rear wheels round by hand and check if the crown wheel is moving round, difficult on a Yam, but you should see it with a light down that filler hole. My guess would be the crown wheel won't go round and you will notice some slop in the LH rear wheel bearing. If this bearing isn't fixed as soon as it goes, the splines on the rear axle get all the load and soon start to wear. If you are lucky, it will just be worn out axle splines, if unlucky, the crown wheel splines will be shot as well. Both are eye wateringly expensive to replace, which is why the previous owner got rid.

 

I have also picked up a 2004 Yamaha Bruin 350 4x4. This thing has lots of issues, but what is warping my brain right now is getting the starter relay wired correctly. I have tried to find colored photos to aid in my untiring efforts or to find some kind of schematic showing me what wires are to go where. I've seen lots of splicing going on and that worries me for a fire. For instance, the start switch has a red wire going into a brown wire. I'm sure if this was from the factory then it would have had shrink wrap on it. Any help would be awesome and a photo speaks volumes...thanks

 

As this has nothing to do with a Yamaha rear end you would have been better to have started a new thread.

Yamaha safety lock-outs for the starter are stupidly complex. Note the blue/white goes into the CDI for no apparent reason, looks like the start button is on the negative side of the solenoid too.