Stripped gear, now what?

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Steveobass

New Member
Jul 16, 2018
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So I just got done with my first build. It's a Zeda 80 firestorm.
Everything was going good, to good I guess. I had just put my third tank of gas in and went out for a ride. The engine started making a terrible noise so I shut it off and started to push it home.
Half way home I noticed the clutch wouldn't engage. So I thought ok clutch needs adjusting.
Wrong! This is what I find when I pull off the cover! What would cause this and what is my course of action?
Also, I'm new to this, but these clutch pad look like crap for only having 2 tanks of gas ran through them, yes? No?
 

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crassius

Well-Known Member
Sep 30, 2012
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someone at CDH factory is forgetting to put grease on that gear - last 40 kits I got have all been dry, but I open all my motors up to check everything and oil & grease where needed before I sell them

only real problem you have now (once you buy another small bevel gear) is that the factory is putting some serious thread lock compound on that bolt which makes it a real job to get off without hammering the crank out of true

once you get it replaced and clean the debris out of the area, you'll have no more problems with it, as I've not seen any other damage caused by that gear failing
 

Steveobass

New Member
Jul 16, 2018
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someone at CDH factory is forgetting to put grease on that gear - last 40 kits I got have all been dry, but I open all my motors up to check everything and oil & grease where needed before I sell them

only real problem you have now (once you buy another small bevel gear) is that the factory is putting some serious thread lock compound on that bolt which makes it a real job to get off without hammering the crank out of true

once you get it replaced and clean the debris out of the area, you'll have no more problems with it, as I've not seen any other damage caused by that gear failing
Funny thing is, I GREASED It before installing the motor.
There is an auto shop around the corner from me, I'll push it over there and have them remove the bolt.
Thank you for your reply
 

crassius

Well-Known Member
Sep 30, 2012
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only other thing I've seen that can damage that gear is if it wasn't seated straight on the tapered shaft, but it has to be REALLY wobbly to eat the teeth

so wobbly you couldn't miss it while turning it for greasing
 

Steveobass

New Member
Jul 16, 2018
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only other thing I've seen that can damage that gear is if it wasn't seated straight on the tapered shaft, but it has to be REALLY wobbly to eat the teeth

so wobbly you couldn't miss it while turning it for greasing
It didnt wobble when I greased it, it doesn't wobble now, the teeth are ground down right in the center, were the fly wheel runs. I'm gonna assume the gear had a crappy hardening job, the metal was soft, and got chewed away by the fly wheel. Wich by the way has zero damage.
I may be wrong here, but, those teeth didnt snap off, they were ground down to nothing.
But, the fly wheel does wobble a bit, you think this is the cause?
And by wobble I mean a couple of mill's.
 

crassius

Well-Known Member
Sep 30, 2012
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the big bevel gear sits on a very loose hub bearing (sometimes loose enough to rattle as it moves), but when clutch is engaged that bearing is locked in place by the pads - whenever the small gear fails, all teeth go away and no damage is done to big gear

there are several threads here with pics
 
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Steveobass

New Member
Jul 16, 2018
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Parts are ordered.
I ordered 5 of them, they are cheap, and I see no reason not to have several on hand.
Thank you for the information
 

kaneto

Member
Jun 6, 2016
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TO ANYBODY WHO IS ABOUT TO CHANGE THE SMALL GEAR
Make sure that when it's fully seated on the crank the shaft is below the area where the special washer and the bolt contact the gear. If that is not the case a spacer should be made so the bolt can actually press on the gear and keep it tight.
 

crassius

Well-Known Member
Sep 30, 2012
4,032
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yes, usually only happens if gear has spun on shaft to wear the taper a bit, but good to check

EDIT: not sure if any of you guys do this, but I save the old lock washers for the head studs that have collapsed flat - they make nice, thick spacer washers for things like this
 
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