1998 Yamaha Venture / Drive Train Noise ?

[opps101]

Hello all, great forum. My wifes 700 Venture has a wicked clunking noise coming from the front of the drive train / track. I thought the drive chain skipped or sprocket chipped a tooth. Opened her up last night, everything in chain drive case appears fine.

Put track up off ground and ran it and clunk was not present? Only when weight off machine is on track does it make the clunk, happens both in reverse and forward, every revoultion of track. Checked track for a rock or something stuck in slide nothing.

Anyone have any suggestions would be great. Third ride since we got this sled and don't want to taking her in and spend more $$$ unless I really have to.
Thanks all,

KC

 

[BIGFOOT]

I would start from the drive clutch & check everything real good thru secondary,Jackshaft,Brake assembly, Chain,Gears, Drive shaft, Bearing,Drivers & onward thru out the suspension. The way you say the sound is pronounced, You should be able to find the problem with some time.... Good luck !

 

[Summiteer]

Track too loose and slipping on the drivers? Wouldn't do it with no load on track.

 

[opps101]

Great, dumb me, didn't even think to check that. Being a newbie, Iam a good 2 stroke dirtbike guy but not a sled guy ( yet !) I noticed when I was inspecting the track that I could put my hand in between the track and the sliders, probably hanging 1 1/4 inch off slider. Thats probably it man. I will let you know, will be wrenching on it in a few hrs...

Cool !
KC

 

[Rucky]

It also could be a chunk of snow that melted off the tunnel, landed on the track....so when you go, it continuously bangs on the front of the tunnel because it cannt squeeze through the tight space in the fron of your track...this happened to me last year, we put it on a sled stand and rotated the track backwards till we could reach the piece, that solves the problem.

 

[Culvert]

The clunk sound, is it only on the initial forward/ reverse movment?
These yamaha's have alot of play in the chaincase and could just be the slak being taken up when first moving?? Or possible suspension, shock loose bolts, transfer rods out of grease and clunking when moving?
If its everytime track goes around? check for bent or missing track clips. One could be hitting drivers or slider tip??


Hope some of these help.

 

[opps101]

The clunk sound, is it only on the initial forward/ reverse movment?
These yamaha's have alot of play in the chaincase and could just be the slak being taken up when first moving?? Or possible suspension, shock loose bolts, transfer rods out of grease and clunking when moving?
If its everytime track goes around? check for bent or missing track clips. One could be hitting drivers or slider tip??


Hope some of these help.

Hi, the clunk is constant the faster you go the louder and quicker the clunk. I jsut pulled the chain case and the next case apart. No shavings nothing bearings are fine on both sides secondary sheave and the front roller shaft. Yes everytime track goes around but only when there is weight on it. It doesn't do it when track is off the ground? I did notice the reverse gear that engages, spring is worn out as well as the large spring that pushes the larger gear to engage reverse/forward. Both gears have one side that is shaved off. You would think the noise is all the time then not just every revolution.

I checked all the track clips why would it not make noise when it is off the ground if it was a track clip. Its getting late. I will let you know what my dealer says when I show them the springs and gears on Tuesday.

Thanks

KC

 

[Culvert]

Couple more things to check on. Pull the secondary off and see what the brg behind it looks like. Also the speedo brg which is behind and below the secondary. The lower speedo brg wears out fast as it get full of water and rusts.

 

[opps101]

Hello all,

Thanks for help. Got her all fixed up late Thursday night. It was a combination of issues. The bearing on drive axle behind speedo was shot and the set screws had come loose allowing the axle to move back and forth, also the drive chain side bolt that holds the reverse gears and primary gear was also loose rubbing against the case. The drive chain was worn out allowing for too much slack.

Going out later today to test it and retighten the track. Happy trails !

Thanks again,

KC

 

[Culvert]

good to hear, thanks for the update. Now I know some of my knowledge is sometimes usefull. LOL

 

[opps101]

Hello again, did all that thought I had it fixed, turn out to be the darn clutch belt!!! Then put the secondary back together wrong and track is too loose, so going at it again tommorow. Lot work when you have to work on three sleds!

Cheers!
KC