PW 50 will not start

[chevymetal]

My brother and I bought a PW 50 yesterday to mess around on. The guy at the shop said he thinks its a 97. We rode it around yesterday and it started up without too much trouble. Today the thing won't start no matter what I do. I don't know alot about two stroke engines unfortunately. I have checked around the net to see if other people had similar problems but everyone elses seems to have not run in a while. I don't see what could have happened this fast. Anyone have any ideas? Thank You

 

[nickyd]

what's it doing? don't those have a start function on the on, off switch (ie, you put it on "start" and then once its running, you switch it to run")?

 

[chevymetal]

Yeah, first kick it started and I switched it to run. As soon as I did that it stalled. I switched it back to start and it won't go now. After about 10 minutes of trying it started again but stalled again when I switched to run. It hasn't run since.

 

[nickyd]

try a new plug - the one my nephews run is sensitive even after a new top end - I usually start it with the choke on and on "start" - I leave it on start for a few seconds (10 maybe) and then switch to run and keep alert with the choke/throttle until she gets warm. you have the bike on the centerstand right? they really need to be on the centerstand when starting.

 

[chevymetal]

Ok I got it started by adjusting the carb screws and giving it just the right amount of throttle. But now it won't idle and it has no power. It didn't yesterday either. Could this mean it needs a rebuild. I checked the air filter and it looks spotless. I don't know how to adjust the carb screws to tune it. I had the exhaust all apart yesterday to remove the governor but the washer didn't look like it would restrict any flow. I removed it anyway and put it all back together. I hope it doesn't need to be rebuilt.

By the way, what is the centerstand? Can you tell I don't know much about bikes? :laugh:

 

[nickyd]

centerstand = kickstand. in this bike's case, it keeps the rear wheel off the ground. sounds to me like you need to adjust the air screw back to where it was - you should be able to turn it out a couple turns after it lightly seats (screwed in to tighten gently) - do this and see if it idles. My PW50 has no power with my 200 + pound arse on it but it screams with my 45 lb nephew on it....if you want a pit bike to put around on get a XR50 or a XR80. .

 

[chevymetal]

Mine doesn't have a centerstand I guess. I suppose i'll just have to get a different bike. I saw people my size driving 50's around nicely but I guess they weren't PW's. Thanks for your help.

 

[chevymetal]

Now the thing has no top end once I get it going a bit. It seems to bog or something. I noticed the cord coming up out of my gas tank isn't connected to anything so maybe it isn't getting enough of a vaccuum effect or something. I don't know where that cord is supposed to go though.

 

[ncflattrack]

Take exhaust pipe off and look in exhaust port. It may be clogged with carbon deposits. Pretty common from what I hear.

 

[Jasle]

the "hose" coming off the tank is not supposed to connect to anything. you need to check your compression. its very common for these to sieze around the exhaust port and you might very well need a new topend. It might not idle because you screwed with the idle adjustment. its the bigger screw. run it in slowly until it ildes. if it goes all the way in and you still cannot ilde you might have an air leak.

 

[todo]

the "hose" coming off the tank is not supposed to connect to anything. you need to check your compression. its very common for these to sieze around the exhaust port and you might very well need a new topend. It might not idle because you screwed with the idle adjustment. its the bigger screw. run it in slowly until it ildes. if it goes all the way in and you still cannot ilde you might have an air leak.

I agree with Jason. I had one a couple of years ago and it needed to have a new top end and all the carbon cleaned out of the pipe. I did all this myself. It is not hard. Also I think there is a switch on the kick stand that will kill the engine if it is the down position. Also spray electronic tuner cleaner in and around the on/off switch on the handlebars. Good luck and hope it helps

Todo

 

[chevymetal]

Thanks for the tips guys. It never idle'd even before I messed around with the carburator. I have tried every setting for the idle screw and it still won't idle properly. Something new happened though, I was riding down the road and all of the sudden it started accelerating like crazy, it went really fast for awhile and seemed to be working better than when I first got it. Then it started chugging a bit and it lost all of the power and is back to the way it was. slow as hell. How would I check the compression? I assume I will need some tool. Maybe it would be better to just take it in and say "fix it".

 

[Joeschmo]

well it sounds like a vacuum leak i think because my gt80 used to do that and the gaskets were all gone so yah thats what i think

 

[Jasle]

might be pricey to "just fix it" have you pulled the carb apart and cleaned it? make sure the jets are clear. you could have clogged up carb and craps getting pulled up. could be a leak but these motor's are not really prone to air leaks except right where the carb clamps to the intake.

 

[chevymetal]

Well now I've done it. I took apart the carb and cleaned it all out. There was some dirt in the bottom bowl shaped area. I put it all back together and fired it up and now it has even less power, next to none. I'm thinking that if there was a leak, now it is worse because of my moving things around. It's not looking good for this little pw.

 

[twoofeach]

Get a grip Chevymetal! You are talking about one of the easiest motorcyles in the world to work on. It runs so that's a great sign. It doesn't sound like you have much experience with bikes. Might I suggest getting a manual. You can pick one up for about $20 and have pictures and instructions for every bolt on that beast. From what you are describing and what other people have contributed, it could be low compression, an air leak, improper jetting, carbon buildup, dirty or blocked carb, etc...you need to eliminate at least a few of those variables before you can get any kind of decent help on this or any forum. Good luck. :cool:

 

[Jasle]

no power

no power usually means low compression. these bikes tend to eat rings around the exhaust port. luckily its not too expensive. do you have a compression tester? Or you can pull the cylinder head off and take a peek at the cylinder. often they need bored oversize with a new piston. uner $200 total for parts.

 

[chevymetal]

I finally worked up the courage to tear the engine apart. It doesn't look like it has ever been apart before. Some of the parts are in rough shape. The head of the piston is all crappy looking and I'm not sure of the condition of the rings, they looked ok though. Anyways I cleaned out a huge amount of carbon build-up and cleaned everything. I took the exhaust all apart again and got all of the carbon out of there too and put my washer back in. (guy at the shop said it was a governor but it obviously wasn't) Anyways I took it outside and expected it not to run at all. Was I ever wrong, it blazes now. I can even accelerate up large hills. I'm sure a professional could get even more out of it but it is certainly fast enough for what I use it for. Anyways I just wanted to thank you all for your help. I'm sure you were all beginning to get tired of my whining. Maybe soon i'll buy a bigger bike because I have a blast on this thing. See ya. :ride:

 

[Jasle]

if there is a washer in your exhause then it IS a restrictor. unless your kid needs the less power take that sucker out. they run much better with the restrictor out. doubles the power. just leave the little crush gasket that the washer used to be glued to in.

 

[chevymetal]

What does this gasket look like? The thing I put back in looked like a washer but it was thick and had grooves running along the inside and outside. It fits perfectly into this little depression in the pipe. the hole in it is as wide as the pipe so that's why I figured it wouldn't restrict anything.

 

[Jasle]

yes your describinge the crush gasket. when new from yam they are a green material inside the metal. there is a very thin washer that glues to that gasket that is the restrictor.

 

[chevymetal]

Ok, the guy who had it before me took the restrictor out I guess.