Lost power

[Coop]

Need some help. I've had this cool beach cruiser with an 80cc motor, really clean, have had it for 1-1/2 months. I was cruising down the road last weekend when all of a sudden the RPM started getting high and power dissappeared. The motor kept running until i killed it, but there was no more drive. My first thoughts were the clutch. I took it apart, cleaned up the pads and put it back together a little tighter but no change. The clutch just doesn't grab. Am i missing something?

 

[Greg58]

Check the key under the small gear on the crankshafts that drives the clutch, it may be sheared.

 

[Coop]

Greg,

Are you referring to the small gear that meshes with the clutch gear, not the chain gear correct? Because if I grab the clutch gear and rotate it by hand it will turn that small gear which in turn brings the piston up and down. It's acting like there is a disconnect between the chain gear and the clutch. What do you think?

 

[Greg58]

You have keys under the large clutch gear and the drive sprocket, either could have sheared. I haven't heard of the clutch shaft breaking but it could happen.

 

[Coop]

Greg,

Your thought about the crankshaft drive sprocket got me thinking that possibly the chain drive sprocket went together in a similar way (I had never taken it apart so i didn't know that it was assembled that way). I went home and took the clutch lever/chain sprocket cover plate off and noticed that the sprocket had started grinding into the cover plate which meant it was "walking off" of the crank shaft. The nut holding the sprocket on the shaft was finger tight and the "key" that should have been in there was gone. So that was the problem. The sprocket just spun on the shaft and that's what made it at first seem like the clutch was slipping. I just fashioned a new little piece of metal to fit in there and put it back together and it worked and got me to work this morning.

So thank you Greg for your idea, I'm back on the road again cooking with gas instead of pedaling my other bike which I've had to the last 4 days. Thanks again!