Sticky Drive Gear

Discussion in '2-Stroke Engines' started by roughrider, Nov 2, 2013.

  1. roughrider

    roughrider Member

    Hey All,

    It's been months since I last posted. Took off this summer and lived out of a backpack in the Northern California mountains by Mt. Shasta-the South Fork of the Sacramento River, to be precise. I was doing an experiment in wild foods, trying to see how far I could go "living off the land."

    (Not far. But I did learn a lot about acorns and oak trees. I wish I had had an air rifle. I could have snagged some squirrels. Trapping sucks. It's unreliable, and to my sensibilities, too cruel a way to get game. Trout, well, I had to be careful not to wipe out the native populations, so I purposely limited that to ten fish a week.)

    I did not ride my motobike all summer! That, and ice, were the two things I missed most.

    Then, when I came back, I swapped out my engine for a spare I'd bought and never used. It's a centerfire type that I bought from Dax. One thing about his motors is that he replaces the bolts and such with good, American steel, and whichever factory he gets them from certainly uses better casting technique than the engines that the Bikeberry consortium sell.

    But even after grinding down the head for more compression and making sure it was broken in, this engine is still not making the power that my older one does. (I do not have a compression tester at the moment. I'm gonna borrow one though just to eliminate that variable.)

    Oddly, I find the chain has jammed in the driving gear every morning, and spinning the wheel by hand definitely gives what seems to be excessive friction. This is the main weird thing I find. Yet when I had the case apart, the bearings all were fine. The clutch is adjusted fine.

    Some additional data. I reground the drive gear so the teeth meshed more smoothy with an 041 chain, and it's the same gear I had on the other engine. I did not have that sticking problem on it though. Also, I have had a Pirate Cycle chain tensioner on both engines.

    (Just to eliminate a low power possibility, after messing with the jet, I got things close enough. I'm running maybe a tiny, itsy bit rich, but no more. Jetting is something I am reasonably confident I understand, thanks to you all who helped me learn that a while back.)

    Any ideas?

    Last edited by a moderator: Dec 16, 2015

  2. roughrider

    roughrider Member

    Well, I answered my own question. The clutch was NOT adjusted properly. It was slipping. This accounted for the extra heat I was noticing too.