1988 Elite E (SB50P) bogs down only when warm
Posted: Mon Jun 16, 2014 3:39 pm
I have an '88 Elite E (SB50P) which I bought about a year ago for some short puttering around town.
When I bought the scooter it ran well. Started first kick, idled well...etc. I took it for a ride around and island near me (gravel covered roads), got about 3 miles into the trip and the scooter died. I was able to restart it but the engine was running really rough. I was able to limp back home with motor sputtering, surging and stalling.
I had the scooter serviced. The mechanic cleaned the carb, air filter, replaced all the fluids..(typical maintenance stuff). The scooter ran better but was still not at 100%. It seemed to bog down when under load (for example, going up a slight hill). It would also bog out if I ran it near full throttle. The engine would sort of sputter, the RPMs would drop, the scooter would decelerate (as if i had quickly grabbed the brake) and then accelerate again. Very unnerving.
I brought it back to the mechanic and he noticed that the airbox had come detached from the carb. He fixed that and the bike ran great!
Excited, I took it out for another short spin around town and it indeed seemed to be running well.
Yesterday, my son took the scooter to pickup some stuff at the grocery store (about 2 miles away). I got a call 15 minutes later saying that scooter had died.
When I got to the scooter I was able to start it on the first kick...the bike will purr at idle but if I give it any gas (even a tiny amount) the motor will bog down almost to the point of stalling.
It seems that the scooter runs great when it's cold. Starts right up, idles perfectly, engine sounds great, no smoke. It accelerates well and goes pretty fast for a 26 year old bike. (I've had it up to 35mph and I'm 220 lbs) However, after a couple of miles (or ~15 minutes), when the engine gets warm it bogs down to the point of barely running.
Here's are some ideas that I've got from reading other posts on this forum:
1) vacuum leak causing fuel pump to not work
2) carb not getting fuel (burning up whats in the bowl, gas not getting replenished)
3) bystarter getting stuck or activating (dumping more fuel into carb) when warm
4) exhaust needs cleaning (back pressure)
5) gas cap not allowing air into tank
6) carb set up with proper enrichment setting but improper run(?) setting
Any ideas? It's a great little scooter and I'd like to be able to ride it for more than 1 to 2 miles at a time.
Thanks.
When I bought the scooter it ran well. Started first kick, idled well...etc. I took it for a ride around and island near me (gravel covered roads), got about 3 miles into the trip and the scooter died. I was able to restart it but the engine was running really rough. I was able to limp back home with motor sputtering, surging and stalling.
I had the scooter serviced. The mechanic cleaned the carb, air filter, replaced all the fluids..(typical maintenance stuff). The scooter ran better but was still not at 100%. It seemed to bog down when under load (for example, going up a slight hill). It would also bog out if I ran it near full throttle. The engine would sort of sputter, the RPMs would drop, the scooter would decelerate (as if i had quickly grabbed the brake) and then accelerate again. Very unnerving.
I brought it back to the mechanic and he noticed that the airbox had come detached from the carb. He fixed that and the bike ran great!
Excited, I took it out for another short spin around town and it indeed seemed to be running well.
Yesterday, my son took the scooter to pickup some stuff at the grocery store (about 2 miles away). I got a call 15 minutes later saying that scooter had died.
When I got to the scooter I was able to start it on the first kick...the bike will purr at idle but if I give it any gas (even a tiny amount) the motor will bog down almost to the point of stalling.
It seems that the scooter runs great when it's cold. Starts right up, idles perfectly, engine sounds great, no smoke. It accelerates well and goes pretty fast for a 26 year old bike. (I've had it up to 35mph and I'm 220 lbs) However, after a couple of miles (or ~15 minutes), when the engine gets warm it bogs down to the point of barely running.
Here's are some ideas that I've got from reading other posts on this forum:
1) vacuum leak causing fuel pump to not work
2) carb not getting fuel (burning up whats in the bowl, gas not getting replenished)
3) bystarter getting stuck or activating (dumping more fuel into carb) when warm
4) exhaust needs cleaning (back pressure)
5) gas cap not allowing air into tank
6) carb set up with proper enrichment setting but improper run(?) setting
Any ideas? It's a great little scooter and I'd like to be able to ride it for more than 1 to 2 miles at a time.
Thanks.