pw50 runing like a hairy goat

japminisrider · Jul 31, 2011

hi all new to the site and was wondering if any 1 can give my some advise with my heavily moded pw50 it starts with full choke and half throtle then if u hold the throtle for a while it will idile rufly in the start position only to stall in when switched over to run. but if u start it leave it in start mode then disconnect the kill/start/run switch it will run like a dream only thing is that it wont start with the switch disconncted. dont have a huge amount of knowledge with the pw's. help plzz

japminisrider · Jul 31, 2011

btw it normaly starts with the switch disconnected

The_GDFP · Jul 31, 2011

Can you define "heavily modded"? There are varying ideas as to what that means

What it sounds like, is plugged up. The exhaust ports are notorious for filling with carbon and sludge. That and/or it's just wore out. They're tough, but still need a top end job now and then. Of course, you've put in a clean plug, fresh gas, cleaned the air filter, right?

Here's a "lightly modded" outline:

Make sure #2 has been removed, and peer in to port for blockage. If that isn't it, remove #13 TEMPORARILY to see if it's plugged. Remove rear screw and pull insert out to clean it, if silencer removal helps:

Drill a couple of 12-15mm holes in the top of #12, OR drop main jet by 2 sizes:

Reduce pump stroke to .5-.6mm and use premium injector oil:

Have head #1 milled 1mm, switch to a 5-6 heat range plug:

Replace #15 clutch springs with stronger ones for higher stall:

Slightly less mild, QT moped rear gears are a lot shorter for acceleration.
60cc jug from 3-4 wheeler bolts right on, has bigger ports.
FMF has a pipe, and there are low-pipes for flattrack.

japminisrider · Jul 31, 2011

yes i have put clean gas/plug and cleaned air filter. by moded i mean boyesen racing reeds, weisco piston and rings

japminisrider · Jul 31, 2011

and stronger clutch springs

dafunk · Jul 31, 2011

its the switch
you disconnect it and it goes sweet
yes they will only start in start position

japminisrider · Jul 31, 2011

but the bike will not start when the switch is disconnected when it normaly would. at the moment to get it going sweet i need to put the switch in start full choke half throttle then let it idel and disconnect the switch. then it idels and runs all good