I took my scrambler 400 4x4 tranny out and replaced all the bearings and seals.Put it back together, took it out for a test run and I get a loud whineing noise in foward, only under acceleration, My buddy said I put the chain on the opposite way, so I took it out again switched the chain and tried that. Same thing loud whineing noise. It dosent do it in revese, or if I remove the sprocket and rev it up in gear, no noise, only under load. Im thinking maybee replacing the chains. Any suggestions? thanks.

 

I've got some ideas for you, these are just ideas. Is the fluid in the transmission low? Could it possibly be coming from your clutches? Did you replace the clutch cover correctly, is the clutch rubbing the cover? Did you replace the belt going the same direction as it was when you took it off? If it is coming from the tranny it could only be about three things, worn or damaged bearings, but you just replaced them.. so, low oil, metal chips jamming in the gear teeth. It sounds like it could be either clutch or trans to me, but without being there and hearing it, it is hard to tell.

 

Check your transmision for alignment stand in back of your bike look at the chain is it bowed or it could be your clutches out of alignment check those also. you will have to get a clutch alignment tool to check your clutches but your dealer should have one if he is a good guy he should let you borrow it.
Hope this helps

 

I was thinking that too Alpine, but doesn't the trans just bolt in without shims and crap like the motor? I am not sure, but I thought It was.

 

Hot Seat has a really nifty (simple yet effective) alignment jig. Slides over the engine shaft and the trans shaft, along with their other alignment tool. I'd go with what NC suggested (it's easier to check first) I've had the cover get tagged before, and you wonder "what the heck is that".

 

Yeah I thought maybe clutch so I removed the cover front and back, test rode it, same thing. I didnt check for alinment though. The chains Im not sure about. But if it is the chains they should wear in? I will check on all the suggestions. Thanks guys.

 

NCScrambler
Yes you are right but, you could still have a twist to it putting it back in nothing ever goes back together perfect we all know that....lol.
I agree with modquad too NCScrambler ideas should be checked first.

 

Do you have the concentric drive? If so, another possibility could be the right-angle joint coming out the front. If the gears are 'set' too tight, it can whine there, too.
But go over all the other stuff first, this one is unlikely, but possible.

 

just an idea, also, anytime you have these transmissions apart, it's always a great idea, especially on the 4x4 units, to replace the internal chain. Just swapped my 99 stocker out, and wow, that puppy was streeeeetched out. $30-40 of cheap insurance.

 

Thanks Alpine, wasn't sure how good the trans. went back in, haven't had to deal with that yet, thank goodness. Appreciate the info. Hey there's always wishful thinking that everything will just fall right back into place. LOL