Kreidler mp9 transmission leak

Your Gerlfriend /

Just got this Kreidler up and running!


all things considered, i think it runs pretty well, except for all the transmission fluid leaking out of the top, right where the bolt that holds the clutch lever is. what is and how fix??


the decomp valve is leaking some smoke and gas out, but i think once i stick a plain bolt in that hole to forreal seal it, it should be fine

any advice for making this go better? im pretty new to this so i kinda need it

Re: Kreidler mp9 transmission leak

Pretty sure there's a seal that can be replaced under the clutch lever .

Re: Kreidler mp9 transmission leak

Blake Totally a real doctor /

Ditch the decomp ASAP. They're unnecessary and prone to failure.

Your leak is super common. Apparently the plug around the clutch arm pulls out and the seal is replaceable.

Re: Kreidler mp9 transmission leak

Your transmission fluid doesn’t look right?

Kreidler mp9 transmission leak! update: now not turning over :(

Your Gerlfriend /

updates! decomp is fixed! plugged it with the right size bolt and some JBweld, no compression issues there.

transmission leak is identified, its an O ring gone bad under there, ive just gotta go get the right size, unscrew that bolt and then put it back on. I'm doing that in the morning.

new issues:

while i was fixing the decomp bolt, i put on a new domino throttle.

i test next day, kicks over just fine, no more air gas or smoke getting in or out of the holes. but the throttle cable was too tight so it was just kinda stuck on and ripping. i turn it off and adjust the cable so its a hair looser and it all seems to be exactly as it should, but now the motor wont turn over?

i jigged around trying to adjust the throttle so it would go, to no avail.

checked spark, thats fine.

I think it might not be getting enough gas? the tank on there is huge and the fuel line has to go down and then up? i dont know, that doesnt make a lot of sense because it was running just fine earlier.

also worth noting, there's no choke plate in the carb, so all the fuel from the line just leaks out the air filter hole once i turn it off and close the petcock. ive cleaned out the air filter a couple times, hasnt helped?

before i haul off and start buying more parts, what should I do?

new carb? smaller tank?

thanks for the help so far, this is my first moped and foray into two wheeled motor operation at all, and i really enjoy all the tinkering. brap?

Re: Kreidler mp9 transmission leak! update: now not turning over :(

Sounds like you need to insure the float needle is copacetic .

Set the float level .

Polish the seat to a mirror shine .

Make sure the needle tip is as it should be : clean , straight bevel , with no cupping or imperfections .

Re: Kreidler mp9 transmission leak

could you give me an update on how you fixed the leaky clutch lever? I replaced my o-ring and it's still leaking, and now the clutch won't engage when trying to start it. I took apart the transmission but I figured I would ask before having to make a clutch removal tool, I think that I accidentally pulled the clutch lever too far up when replacing the o-ring and disengaged something in the transmission.

Re: Kreidler mp9 transmission leak

Hello I have a 1978 kreidler Mp9 and there is a leak on top of transmission where lever bolt is. If I take the lever off to replace o'ring will the shaft drop down? And does anyone know where I can buy correct size o'ring? Thanks 😊


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