Engage clutch, engine starts "bucking".

[WannaBee]

Hello all, total noob to the motorized bike world, though worked as a mechanic for decades. My engine is a Bikeberry 66cc flying horse and here is my issue: Disengage clutch and start engine, all is well. With bike on a stand, rear wheel off the ground I slowly engage clutch. Wheel starts spinning, all is right with the world. However once the clutch is FULLY engaged, the motor starts bucking and jumping. Does this whether I'm on it or have it on the stand. I have good chain tension, no kinks at the drive gear. I suspect the bearings in the clutch gear are too few( can see the bearings, major gaps between them) and/or the gear is too loose ( lot of in and out slop in gear). Any similar issues with possible solutions, I'd love to here from you, and thank you.

 

[Member 30571]

Welcome to MotoredBikes.....My first bike did the same thing...tighten the small gear and tap it lightly so theres no wobble

 

[WannaBee]

I did notice that the small gear protrudes out from the case, where it is not very well lined up with the clutch gear. Guessing I check for wobble,remove the screw, tap small gear into submission and replace screw? Really appreciate the advice, Bikeberry hasn't returned any calls/emails since I made the purchase.

 

[HumanPerson]

I did notice that the small gear protrudes out from the case, where it is not very well lined up with the clutch gear. Guessing I check for wobble,remove the screw, tap small gear into submission and replace screw? Really appreciate the advice, Bikeberry hasn't returned any calls/emails since I made the purchase.

Replace the bevel gear bolt with this:

HEAVY DUTY Small Bevel Gear, ALLEN-HEAD SCREW and Copper Shim for 66/80cc Motor | eBay

Find many great new & used options and get the best deals for HEAVY DUTY Small Bevel Gear, ALLEN-HEAD SCREW and Copper Shim for 66/80cc Motor at the best online prices at eBay! Free shipping for many products!

www.ebay.com

 

[HumanPerson]

Stop using bikeberry

 

[Chainlube]

Can you stay on for 8 seconds? LOL!

 

[HumanPerson]

Tightened at all points of contact at the mounting points?

Front mount bolts al the way in and tight?
Nuts tight?

Rear mount bolts all the way in and tight?
Nuts tight there?

How is the fit on the front mount to the frame, loose like to wide or does it fit snug?

 

[HumanPerson]

Can you stay on for 8 seconds? LOL!

Sometimes 10 seconds

 

[WannaBee]

Stop using bikeberry

Yup, first and last time for them.

 

[WannaBee]

Tightened at all points of contact at the mounting points?

Front mount bolts al the way in and tight?
Nuts tight?

Rear mount bolts all the way in and tight?
Nuts tight there?

How is the fit on the front mount to the frame, loose like to wide or does it fit snug?

All hardware is snug. It's a 1957 Murray Westport, steel frame 1" dia all around.