Bet & Win 150 Idle Problems + Axxess Key Size

[heypete]

Hi folks,

Over the last month or two, my B&W 150 was idling really poorly: idle speed was erratic and low, and the engine frequently stalled at idle, even when warm. As most of my trips are pretty short, the engine doesn't warm up all the way, so I thought it might have been a bystarter problem, out-of-adjustment valves, or maybe the idle speed screw needing adjustment.

Turns out it was considerably easier: there was a vacuum hose on the carb that was cracked. After some trial and error, I confirmed that this was the cause of the problem, and replaced it. It turns out the second-smallest vacuum hose at PepBoys ($1.39 + tax) fits perfectly (though the outside diameter is a bit larger) and the problem is now solved. Woot.

Things run considerably better, and the idle never drops below about 1,500 rpm at the lowest but quickly returns to (and stays at) 1,800-2,000 rpm.

Also, while I was at PepBoys, I decided to get a new key cut for the scooter. Unfortunately, I didn't know what size to get, so I bought three different blanks and had them cut all three. Turns out the Axxess+ size 30 fits well (the other two, a 24 and 32 I believe) were too thick. The 30 seems just a hair thicker than the Kymco key, so it fits a bit more snugly, but it works. Hopefully this information helps someone in the future.

[Hoolander2]

Excellent tip -- thanks heypete.  Helpful to all models probably.

[wordslinger]

Over the last month or two, my B&W 150 was idling really poorly: idle speed was erratic and low, and the engine frequently stalled at idle, even when warm. As most of my trips are pretty short, the engine doesn't warm up all the way, so I thought it might have been a bystarter problem, out-of-adjustment valves, or maybe the idle speed screw needing adjustment.

Turns out it was considerably easier: there was a vacuum hose on the carb that was cracked.


..the vacuum circuit controls the ability to deliver fuel to the carb...

..awesome fix heypete!!

 

[heypete]

Thanks. I hope it's useful for people trying to diagnose weird idle issues -- it sure beats fiddling around with adjusting the idle speed screws, discovering they're not at fault, and trying to get them back to the right setting. That, or forking over the ~$70 the local mechanic wants for repair work.

For what it's worth, the vacuum hoses Kymco put on this scooter are a bit thin and seem a bit prone to cracking. The replacement line I put in was thicker, and will hopefully hold up better.

It's kinda fun working on these little engines.

[wordslinger]

..i have replaced all my vacuum tubing...i too noticed some cracking at around 40,000kms..

..even on lines i had never handled...

[j2]

Hmmmmm I have the reverse problem with my Kymco BW 150. It is idling about 4K. I reset the mixture to factory specs and set the speed screw on the linkage so that it would idle at around 2K ... a little fast, but OK. I noticed it was surging. Started it a week later. It started almost instantly and went directly to 4K, where the idle stayed, even when the engine got warm. I am suspecting maybe a vacuum problem or something else afoul with that steeenking bistarter (hate those ... much prefer a manual choke). Anybody have a similar problem and hopefully a solution?

[wordslinger]

steeenking bistarter

..that'd be my guess!!

..welcome to th' Forum!!

 


peace

[j2]

Checked the resistance across the bistarter ... measures less than the 10 ohm spec, but I am using a cheap meter. I would think that, if it measures about 7 ohms, the switch might still be closing OK. Very hard to tell. I should probably replace the stupid thing. I got over four years on the original, so I have probably seen my money's worth out of it. Why, oh why did they have to put those in instead of simple, manual chokes!

You mentioned that you changed vacuum hoses. I took one look through the inspection door under the seat, and Oh Crap! Looks like spaghetti down there. It has hoses all over the engine .. some with T connections ... some look like vacuum hoses but appear to lead into wiring harnesses. There is one up top on the vacuum chamber that loops over and terminates in the air (nothing-goes nowhere). There is a smaller, short hose that does a quick loop to the ACV (air cutoff valve). I know some of these have to be fuel delivery hoses and some are probably pollution control junk. Long story short: I have no idea which of these hoses is/are actually vacuum hoses that might need replacing. Which did you replace?

[wordslinger]

..well, i don't have a b&w...but there ar only a cpl or three circuits there...

..the vac circuit could be traced by locating the tube that is connected to the engine's intake....