Pocketbike Forum banner

1 - 6 of 6 Posts

·
Registered
Joined
·
5 Posts
Discussion Starter #1
Hello all... glad to find a forum only for mini bikes. I got a coleman ct200u-ex...ive done some mods..echaust, intake filter and carb modify. And redone the throttle assembly and governor delete. Ive changed to the #40 clutch and sprokets, on the jackshaft also. But now im getting a really bad vibration in the bike at half throttle and beyond. I went to the #40 chain setup because i thought it was a heaver duty chain. Did i go wrong? There is no way to adjust the slack in the drive chain from the clutch to the jackshaft..and thays where i thjnk im getting the vibrations. Only way to tighten chain is to use a half link. The tension roller is baisically against the jackshaft sprocket. What am i missing? Where do I look next? Any help on this is greatly appreciated. Is there a way to do away with the jackshaft altogether? Has any one had this issue and corrected it?
 

·
Super Moderator
Joined
·
2,180 Posts
if you put the stock chain and sprockets back on is the problem resolved a half link will only chew up your sprockets you might need to make a chain tensioner or drill out the holes where the engine bolts up to make slots so you can adjust the chain

i would definitely start putting stock parts back on until the vibration goes away to narrow it down
 

·
Registered
Joined
·
5 Posts
Discussion Starter #3
I done that. And the viberations still persisted. I did notice on the jack shaft.. there was play on the bearings. I took out the shaft and put in on the lathe and checked for trueity. Shaft had a wobble on the exposed end where the input and drive sprokets are mounted. Ordered a new shaft, put it n and viberations reduced to near nothing ,, untill you get to cruising speed. I looked best i could at the chains, noticed the bottom end if drive chain was viverating like crazy. Is there supposed to be chain tensioner on that one to? Also noticed the frint shocks acting like they wanted to fold under.. like a knee bending when its supposed to be locked. Other than that..only new updates are i installed a 29 tooth rear drive sproket in place of the 50 tooth. Its a little hatsh on the clutch on takeoff...but she eases into her climb nicely... tops out at 47 with the govenor kicking in about 3200 rpm. But once shes cruising...im st 1/4 throttle, 2200 rpm..shes riding at 24mph. With enough responce throttle and torque , that itll make ya smile...snd with the straught pipe..sounds good too.
 

·
Super Moderator
Joined
·
2,180 Posts
With that said check the variator weights in the CVT transmission if one of the variator weights is hung up it will shake like crazy as the belt tries to climb up the pulley
 

·
Registered
Joined
·
5 Posts
Discussion Starter #6
With that said check the variator weights in the CVT transmission if one of the variator weights is hung up it will shake like crazy as the belt tries to climb up the pulley


CVT transmission?? Ive wondered if I should go go to a belt torque converter instead of the standard clutch that it has. But could you also mean one if the clutch disks?
 
1 - 6 of 6 Posts
Top