Engine died

frozenveinz

frozenveinz

New Member
Heh, I went on a final ride before selling my 66cc bike, and what do you know, the engine died. I have about 600-700 miles on the engine. It never could revv past 6k. Running 87 with 32:1 Pennzoil. Today I ran it at 24:1 Pennzoil to get it lubed up.

When I left it was doing fine, running perfect.

About half hour later, at a stop light, it died at idle. I screwed in the idle switch some, started it up and it ran.

Next stoplight, it started to die again, but I revved it before it could. I noticed it took about 2x as long to return to idle as normal.

Drove off, and the clutch started to slip a bit. Screwed the clutch lever flower nut in some, didn't help. Turned around to go home, figured I'd fix it at home. Halfway there (I started back 4 miles away), it started to slip hardcore, then I pulled in the clutch, and it died promptly. Tried to start er up again after tightening the flower nut completely, but all I got was a bunch of clicking and scraping sounds from the motor.

Walked it the 2 miles home.

Got on motorbicycling.com, posted problem and story.

I think it wast the clutch slipping, but the crankshaft threads got stripped or some bearing jammed and the shaft got milled down.
 
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Well Jimminy Crickett!

Are you Irish?

Sounds like Murphy was there, an active as can be!!!

I guess the lesson to learn is if something is sold, let it set right there until the buyer takes it away???

and the warranty expires as you pass the curb!

Gosh, good luck!
rc
 
I know your pain. 3 of my 5 66CCs didn't like over 6K RPM and failed early.

Might be time to 4-stroke it! When you go that route, the engine itself isn't something you have to worry about much lol
 
Whew! Found the problem. It seems I've sheared my woodruff key. What else should I order? Do I need any new bearings, cylinder, rings, etc at this point in engine life? I hear some kind of chirping when I revv the engine, and as of a few days ago, it happens at idle too.
 
Uh oh, it looks like the inside of the small bevel gear has been milled down a bit by the crank shaft. Is this bad?

Oh darn it, and the small bevel gear cracked. Probly why the key sheared.
 
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unless that 'milling' bit is seriously obvious, I would just replace the sheared key and see how it goes from there.
it might just come back to life and run as it always has???

If things are beginning to loosen up, perhaps it is a good idea to give it regular PM, going over the whole bike, tightening things up that need attention??

Best
rc
 
OK, at $170 or $180 for the whole kit, just how much screwing around does one really want to do? Not trying to sound negative, but it seems to me that these are kind of toss away things when they have big problems. Maybe time to just get a new one?
 
Not big problems. The bevel gear and key I will have to replace. Thats it. Thats $8 of parts...

Although I do think it's time for me to go four stroke. I really wanna, but I can't decide between that or buying a restored vintage garelli top tank. Goes 50mph, climbs, f/r suspension, low vibes, reliability, the whole package for 600 bucks.
 
Is that a Garelli 50 or 90? I had a 50 as a kid and had a ball with it until my dad thought there was a noise coming from the engine, took it apart and that was that. What a shame, neat looking little bikes. Only draw back is from what I remember getting parts can be a real bear.
 
If the crankshaft itself doesn't look too bad, just replace the pinion gear and key. If you still have problems after that it's probably time for an rebuild.
 
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