This damn bike is begging to drive me nuts. Just got it for my boy. It was ugly dirty, but it ran when I bought it. Brought it home stripped it to the frame, cleaned it, greased and lubed everything. Put it back togethor, and now it wont start. Looks great, I need a beer! I dont have a manual for it. I took the carb apart and cleaned it and blew out all the jets etc. I did not touch the air screw or the throttle stop screw. It's got fresh gas and oil. Clean air cleaner. Getting spark too. Compression seems good. The plug just fowls. Do I need to twist the throttle when kicking it over.

By chance anyone know what the stock screw settings are for air screw and throttle stop screw.

Alright, I'm gonna go suck down an Ice cold beer and let this thing rest before I hurt myself!!!

Isn't the JR50 the same as the PW50?
Does it have an oil injector? I have two PW50. One is an '83 the other an '04.
I have the '83 starting with just one kick, cold! it's a champ and the '04 takes a 6-pack to get started and running. Here's what I did on the '83 and gonna do to my '04 this afternoon.
Remove the oil injector! I think that injector mixes the fuel WAY too rich. I'm also premixing at around 40:1 yea, it's a little lean, but Lean is Mean! haha

Oh yeah, its got an oil injector....
Fact I got to a stopping point last night where I had taken the fowled plug out left the GE-rage to post this thread. So I drank a beer, went back a few minutes later, forgot to put the plug back in and kicked it over. Nice....now I have oily fuel spewed out some 10 feet across the floor. Do ya think that had anything to do with the Fosters Oil can I just drank?:smirk: Good thing I wasnt working on this thing it the house! At least, I know its got compression.

Well the coffee is done, it's time to go out there and clean the damn carburetor again. Sadly, when I get done with the Jr 50, I gotta work on the older boys TTR50. Then moms, then mine. oh it's gonna be a long day!

Fouled plugs= Jetting...rejet. if its starting when you put a brand new plug in or hiccuping then it stops then your definitly fouling plugs and need to rejet.

Finally,

She's done.... A gallon of Chem-Dip did the trick. Got all the nooks and crannies cleaned, put her back together and thats all she wrote.... 3 kicks and she fired. Took a bit to burn off all the excess fuel, but with a few minor adjustments to the carb, she's burning good and gave me a couple of solid laps around the block. Plenty of juice for for #3 to get his whistle blowing. Tomorrow we hit the trail. Teach the little man how to handle his new machine.......

Yeah sounds familiar. when we got my boy has JR50 I had to clean the carb 3 times before i finally got it to run. BTW the JR50 oil injector works good, don't get rid of it. The PW50 oil injector is crap I hear but it isn't the same as the JR50's. Your little one looks good on his bike. :thumbsup: My boys too big for his but he's chicken and wouldn't ride on anything bigger.

Thanks xjz, yeah, im with you that oil injector is staying put. I'd rather not mess with mixing gas and oil. Thats just another can I gotta bring along. Ive become thumper lazy... I do miss my "86" YZ250. Uh well maybe not. Then again it sure was fun to ride, minus the killer suspension, NOT!

I knew that carb was gonna need more attention, but when the wife is looking at ya like your nut's trying to explain it. well the forum is the next best thing to vent:banghead: and ask for advice that well, you pretty much already knew, but (A), were looking for some reassuring advice or (B), waiting for that one coment about how you need to do a search because this question has been asked 100 times over, and/or C, hopefull that there is a hometown local who would come over and do the work for ya while you watch and drink beer.:cheers:

Me, I was banking on C of course I would share the beer.:smirk:

you gotta be patient with them kids. I got 2 boys, the older is timid and rides with caution. I just let him go at his own pace. He will get on it when he's ready. The younger one well, he scares me already, he got mad at me sunday morning and said he could start the bike if I couldnt.... Uh.... Yeah! Sitting on his bike at 4 years of age and talking smack to his older brother and me. Think the moto gods have possessed another.. Oh it gets better. I got training wheels for this little machine and He got upset because I mentioned i might put them on just to get him going.. No dad he says, i dont need training wheels, i can ride without them on my bike(BMX). So today we are gonna find out....

It's good that it's fixed. Carb problems on the tiny bikes are sometimes a pain, and on the smokers, if you kick them long enough, the crank case will partially fill with fuel, so it's now super rich and won't fire, but will foul plugs.
The oil injector has nothing to do with this problem, it can happen on pre-mix too.
In general, you want that oil injector, the only time you should remove it is if it dies, which is extremely rare.

I bet the other poster who said he fixed it by removing the oil injector fixed the problem with a by-product of disassembling the engine that far, it gave it time to breath and dried out the crank case enough to fire.

Throw the training wheels in the trash. If you want to help him out, take the pegs off, let him push it around for a while with his legs to get the feel of how the bike moves. Put the pegs back on, fire it up and let him go. Training wheels teach kids to ride the wrong way and hinder progress. Falling sucks, but they'll get used to it pretty quick.

I said I didn't know if the injector was similar to the one on a PW. I'm telling you, my PW was WAY too rich with it.
Someone mentioned to me you can adjust how much oil it injects. If that's the case, I'd leave it all day long, but I don't see how to do that.

Since the JR50 isn't anything like the PW50 I'll go ahead leave this thread.