Modern Buddy

My brother has a buddy 50 (1000 miles) that he rides everyday. The other day I changed the plug on it ( old one was black ) and when he went for his nightly cruise it stalled out and wouldn't start for like ten minutes. It was running perfectly before that but just crapped out after riding WOT for like 1/2 hour.

I did mess with that black knob on the carb which i though was an idle adjuster screw, but now I fear it was an air fuel mixture screw.

If that is the problem then great, does anyone know how to set that screw so that it doesn't foul out the plug? Is there a technique to do that? Or is it a trial and error thing.

Does the plug need to be gapped? After a 15 mile ride the plug is pretty dark.

not sure if its the issue, but a 50 riding at WOT for a half hour straight will not be good on the engine.

IMHO, it should be able to take that kind of riding. What does a black plug mean? Running rich? Maybe the mix is off?

that's what I think. I think the mix is off. Is the black screw coming from the carb. a fuel air screw or idle adjuster? The manual says it's an idle adjuster but turning that would not make it run lean/ or rich.

the longevity of the engine will be compromised if you are floored and maxed out for super long periods of time. Generally if you need to go alot faster then bump up to a 125 so the RPM is not maxed out at the same speeds. I'm not saying this is your issue, just something to keep in mind.

I called the dealer, they said the screw is just an idle adjuster and the reason it's stalling is because the coil is overheating. I'll try that next.

Riding WOT won't hurt your scooter. If it did mine would have blown up 20,000 miles ago. That said, riding WOT on a poorly or improperly tuned scooter will certainly do damage. So will riding slowly. If you are guessing about such important things as getting the fuel mix right I'd suggest taking it to a trained Genuine mechanic and having it professionally tuned.

Skootz Kabootz wrote:Riding WOT won't hurt your scooter. If it did mine would have blown up 20,000 miles ago. That said, riding WOT on a poorly or improperly tuned scooter will certainly do damage. So will riding slowly. If you are guessing about such important things as getting the fuel mix right I'd suggest taking it to a trained Genuine mechanic and having it professionally tuned.

Well the OP was talking about a 2t. That said 30 minutes WOT aint that long.

A properly functioning 50cc will not have any trouble going WOT for half an hour; they can go several times that long without complaint.

check the air filter?

You asked if the plug needed gapping. That depends: what was the gap measurement compared to what it needs to be? Sometimes my plugs were the correct gap out of the box, sometimes they weren't.

I went on a longer ride today (about70+miles) I went over 45 easily for a very long time, and my Buddy 50cc did extremely well, and handled good, didnt seem to have any problems.

Ok got it. It was the cdi. I just got a fancy aluminum one from amazon for 15 bucks. Runs great!