Slow Puch

So I got a new Puch the other day. It looks to be in great condition. After some small work I got it running - but it's not running so great.

It's quick as hell off the line, but he put a smaller front sprocket on there, so that would explain that. But it tops out at like 15mph. The carb it came with was absolutely disgusting, so I put my newports 12mm on it and it did the same thing. It has a 52 jet in there, but it feels like it's getting too much air. When you pull on the throttle it bogs, but if you just give it a little gas it shoots up to 15.

The cylinder and piston looked great. When I turn the flywheel, and lean up to the piston, I hear a very slight "psssssss" like some air is barely squeezing out. Is that normal?

Also, it's pretty loud. I dunno if it's bearings or what, but the engine is just plain loud. A dull "rraaahhhhh" noise.

Any help is appreciated!



Re: Slow Puch

Smitty Smith /

While you have it running on the centerstand, spray WD-40 around all of the gasket mating surfaces...such as, head to cylinder, intake to cylinder, carb to intake, exhaust flange to cylinder, cylinder base to crankcase, and crankcase seam. If you do not find the airleak there, check the crankshaft seal underneath the flywheel.

Hope this helps, hope you find the problem and fix it, and want to hear how fast you get it going after you fix it!!!



Re: Slow Puch

Smitty Smith /

Also check that the sparkplug has a sealing ring, and is tight as well.

Re: Slow Puch

Aaaaaiiiirrrr leeaakkk!

I forgot - one of the bolts that holds the cylinder on is messed up. It seems that the threading on the BASE of the engine is gone. The nut is fully on the outside end, and it will just keep spin-spin-spinning. When I sprayed carb cleaner on that side, it speeds up a little and sputters the carb cleaner all around.

What to do?! I'm dreading to hear you tell me that I need a new case.

Re: Slow Puch

humm, you can probably go to a good motorcycle shop and ask them to do an helicoil, this repairs the thread really good


Re: Slow Puch

erg, I was hoping to not take the engine off the bike. I bought this bike to sell, and I wanted to get it out this afternoon.

Would that small leak be responsible for the speed?

Re: Slow Puch

Okay now it seems I can't even get that bolt out now. It just spins and spins, but it won't pull out. I even tried removing all of them and pulling the cylinder head - but no luck.

What do I do from here?

Re: Slow Puch

George Smith /

take a large sledge hammer something around 12lbs or so and hit it very hard it will fall off.......actually this is gonna be hard to explain but here's how i got one off once......if you have any play in the bolt at all you can pull the cylinder or just the head forward enough to cut the bolt with a hacksaw but be carefull not to cut anything but the bolt.....then maybe you can take the rest off with vice grips....costs you a bolt stud but sometimes it's easiest way

Re: Slow Puch

I just got up frome the garage, and thank goodness it turns out the casing isn't stripped. It's just the outer threading is stripped, and the bolt spins around that.

Actually 2 of them are in pretty bad shape - so I guess I gotta buy a new set.

How do you get the big screws into the base really tight? I don't want to tear up the metal with a vice grip or anything.



Re: Slow Puch

Okay so I fixed the air leak issue - but now it's still going like 15.

Carb seems fine. Could this be points?



Re: Slow Puch

Try cleaning your carb again. The low speed jet may be the cause. Also check your muffler to see if it needs a good cleaning. Just make sure your carb is really rally clean. Use Carb cleaner in a can then air pressure to blow it out. Soak it if you have too.

Re: Slow Puch

no moped no cry /

take cylinder off, clean exhuast port, check for clogged muffler, make sure that was your only airleak, freds guide etc.

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