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Old 04-20-2019, 10:09 AM
belouder belouder is offline
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Default Coleman CT100 governor removal-help?

Hey,

Just found this forum. We have 2 Coleman CT100U minibikes for our growing boys. Is there a link to How-To for removing the throttle governor (not bypassing with wire) that someone can direct me to? I understand it involves opening up the crankcase but am not sure what parts to remove/disable and what to leave in place.

Thanks,
BK
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Old 04-21-2019, 03:38 AM
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itsid itsid is offline
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in the crankcase you find a small plastic gear (< 2")
with a metal contraption in it's center (some flyweights springs and a pin)
that's the governor gear that has to go!

behind it on it's shaft there's a small (usually)metal washer,
you need to remove that as well
(or it'll end up flying around the crankcase eventually sticking on something important causing issues )

The shaft itself can stay in place, if you remove it you need to plug the hole with a bolt.

governor arm and lever can be removed if you like (I would)
if you remove the arm [the part that passes through the crankcase]
again plug the hole with a bolt.

And that's all there is to it internally.

externally you need to reroute the throttle cable so it bypasses the governor lever.
and directly actuates the carb's butterfly.

'sid
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Old 04-22-2019, 11:01 AM
belouder belouder is offline
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'sid,
Thanks for the info. I'm curious about what the governor actually "governs": is it just a throttle limiter that kicks in when the engine revs beyond a certain limit (determined by the spinning weights)? Or does it also somehow limit ignition timing?

If it's just limiting the throttle, wouldn't just bypassing the outside-the-crankcase mechanism (throttle cable routed directly to carburetor throttle arm) bypass this? What does removing the internal mechanism do?

Thanks,
Belouder
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Old 04-22-2019, 01:10 PM
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Yes you can bypass it externally, but then if you rev it too high, the governor mechanism(which is not designed for a lot of rpm), will fly apart and bounce around inside your crankcase, wreaking all sorts of unholiness.
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Old 04-22-2019, 07:02 PM
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No you cannot bypass it.
the reasons are as JT explained, but since he started with "Yes you can"
I must correct this to "NO you CANNOT!"
Since it WILl desintegrade eventually and will cause mayhem..
with a ton of luck your engine stucks and cannot be restarted at one point,
if you're unlucky something wedges itself to the camshaft gear at high rpms and the con rod breaks
And some crank case parts come flying your way.
The chance of NOTHING bad happening is ZERO, therefor you cannot not without a serious risk of at least destroying the engine worse getting hurt really badly in the process of destruction.

The governor is not 'just' a rev limiter..
it's it's main function indeed, but it does in fact govern (not just limit) the rpm..

With a governor you set rpm and the governor sets the butterfly position to keep that rpm a constant as good as it can
say adding a bag of plaster to a cement mixer increasing the load...
it's an industrial engine mind you
or running through a patch of tall grass on your lawn with your mower
etc.

And resets the butterfly back when the load is being removed
(tall grass is cut, cement mixer emptied out etc)
you don't want it to rev up in such cases.. so it set's the butterfly back to govern the rotational speed.

And yes it also LIMITS the max rpm, just to keep the engine from free revving in fact
(unbalanced mower blades at 5k rpm cannot be stopped by modern pressed steel covers I bet )

On a kart /mini bike you always have your hand or foot at the throttle
and can adjust yourself to keep the rpm constant (like you would in your car or on your motorbike)
So you don't need the 'cruise control' feature here as much
(especially since you can't use it as such to let go of the throttle anyways)

And the ONLY safe way to get rid of that (and it's limiting function) is to REMOVE it.

'sid
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