Only 20 mph?

I've got a Puch Murray, e50, Techno Boss, Autozone breather air filter, 14 mm Bing, 15/45 gearing.

I was hoping to get somewhere close to 30 mph at least, but I just had my friend follow me on flat ground and I was going about 20. I'm looking for some thoughts/ ideas. I know it needs some tuning, so here is some more info:

I tried doing plug chops but for some reason it wouldn't die. When I took out the jet, it was 68, so I put in a 72. When I just looked at the spread-sheet, there is a guy with a similar setup running a 64 jet. huh?

Also will not idle at all. I have to keep on the throttle.

I also had tried the gearing 17/45, but took it off to see what stock was like.

(I bought the bike for $50 non running, cleaned it, painted it, and started it up the other night. Tried some tuning today...)

Re: Only 20 mph?

use the choke to kill it if the switch doesn't work. Plug chop. Does your cylinder have that 9mm restrictorin the intake? if it does, pull that sucker out. Adjust the idle screw on the side of the carb.

Re: Only 20 mph?

Also, the headlight is very dull... not sure if that makes a difference or if I just need to get a bulb.

Re: Only 20 mph?

yup its a moped

Re: Only 20 mph?

The light gets brighter as it revs up. It shouldn't have anything to do with preformance.

Re: Only 20 mph?

The light actually doesn't seem to get any brighter when its reved...

Also I see no restriction thingy. Thanks for the choke tip- I'll try that. I tried adjusting the screw, no luck. Does 72 sound too high?

Re: Only 20 mph?

How does it run? Does it four stroke at top speed?

Re: Only 20 mph?

feels like it runs fine- I'm new to mopeds honestly, but I don't think it is fourstroking. That means the mix is about right, right? I am assuming it would be pretty obvious that I were if I were 4 stroking it. That's what I don't understand. Why isn't it going faster?

Re: Only 20 mph?

Is your intake still 12mm?

72 seems high to me.

Re: Only 20 mph?

Its 14mm also, and 15/45 gearing. Jake I took off the 17 and put the 15 back on. It went just little faster with the 17.

Re: Only 20 mph?

interesting. We had a really similar situation with sean's maxi. He has a very similar setup, 15 bing and a boss pipe. I'd like to look and see if your intake in really restricted.

Anyone else have any other ideas?

Re: Only 20 mph?

Have you checked for air leaks?

Re: Only 20 mph?

Also 72 seems high to me too.

Re: Only 20 mph?

That jet's huge, I run a 62-64. You are almost certainly suffering from an air leak, and someone tried to compensate with bigger jets. Idle the bike (or just kinda keep it running) Take a can of carb cleaner and spray a little close spritz on anywhere two joints meet, in and around the carb/intake, shield the air cleaner so none gets in that way. If the bike changes speed at all (revs or dies) when you spray, you have an air leak there. My guess is you have an intake/carb clamp leak.

Also check inside your magneto cover, under the flywheel; while the bike is switched off, hand turn the flywheel around a bit, kinda sharply and listen for a "shoop" sound from right inside the flywheel, this is a bad engine seal, and air is being sucked in. Even seemingly small air leaks are a huge deal with these lil engines, so be keen.

Fix all leaks, not an option.

Set your needle clip at second from top position on needle and get a #60-64, or try that 68 again with lots of easy air flow.

I run a 15x41. 39 on flats. Still can't do hills super great, but better.

Re: Only 20 mph?

I'll check these out- thanks guys!

Only 20 mph?

I think that you need to get a new petcock. You are getting fuel from the tank, for sure. But not enough. The petcock is probably broken (or clogged). Check it out, I had the same problem with mine, turns out the petcock was snapped.

People just don't know how to take petcocks off, they end up twisting the whole thing off and snapping it apart, instead of just turning that nut.

I really think that could be your problem. good luck.

Re: Only 20 mph?

timing

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