Buddy 50 (2015) Stalls under load

[zanetti2000]

2015 Buddy 50, 9000 miles, stock everything I believe
bike had been sitting unused for 11 months
idles o.k. has all fresh fuel, new spark plug,
throttles up well on work stand,
blows a little bit of smoke
carb has been apart and cleaned well
(Keihin PB carburetor 086A GA1)
fuel line running strong, unhindered to carb.
bowl is full (not sure of level) when inspected

problem is: will not go over 15 mph under load (large me on it)
engine cuts out badly over 15-17 mph.
can run at 15 mph w/o problems.
i have run it about 5 miles and no improvement.

[tenders]

Sounds like the main jet is clogged up or there is an air leak. Are you certain the little tube between the air box and the carb intake is fully seated and tightly sealed all the way around the carb? Is the cap screwing down the throttle (the one that contains/compresses the spring and needle valve inside) fully tight?

[zanetti2000]

I'll pull the carb off and check the passages again. I can see and blow air clearly through the main jet and pilot jet. But maybe some other passages might clogged.

There is an Amazon sold carburetor titled "Monster Motion 19 mm PZ19J Carburetor for 2-Stroke 50cc 1E40QMB Engines with Fuel Filter" for only $25 that I am tempted to order. Description says it works for Buddy 50.

Thanks for your help.

[tenders]

I don't think that carb will fit without substantial modification. Note how the carb exit, the big hole, has no flange or holes through which to mount it to the engine intake.

But you aren't in replace-the-carb territory yet, in my opinion. You have some small misadjustment, crack, or gap that is causing this that will clear everything up once you find it. Be ruthlessly methodical and you'll find it.

[sc00ter]

Could it also be transmission related? 9000 miles is rather high. If that's accurate, when was the belt last done? Clutch springs, rollers, slides? Could be engaging the the transmission to early. Just a thought.

[zanetti2000]

bit of an update -

I bought this dirt cheap carburetor via Amazon.
https://www.amazon.com/gp/product/B07BK ... UTF8&psc=1

I'm hoping to drop it in this Buddy 50 and have it magically fix the 'stalling under load' problem. I mean it cost $13 so ya know it has to be quality.

[tenders]

I look forward to hearing how this works out. I would not have bet my $13 that this connects readily or usably to the Buddy 50. If it did, we would already be aware of the various carbs that could be used as substitutes for our particular Keihin PB carb. I’d be delighted to be wrong, though!

[zanetti2000]

the clincher is easy free returns with Amazon. As you may know, you barely have to do more than put an item back in the box, check the right boxes with Amazon and UPS comes out with a pre-printed label in hand to slap on the box. No charge.
So that was my chief motivating factor in going in this direction.
That and someone in the Q&A of the carb said it worked on a Buddy 50.

But I agree, we'll both be amazed it this works.

I'm doing this for the young daughter of a friend who died. She can't afford to pay for a proper repair shop fix. I replaced the rear tire and front brakes and was hoping it ran fine. It didn't. So I feel committed to the repair.

I do appreciate the help offered here. And will be sure to update the results.
(Too bad its so hard to post pics here.)

[sc00ter]

Your 50cc Buddy sounds like my "I may be getting a Pink Buddy 50" thread. Ultrasonic the carb and jets. Also go thru the transmission. I forgot about that little project.

[zanetti2000]

Finally updating my suspected carb issue.
The Amazon purchased very cheap carb didn't fit. the bowl hung down and hit the transfer case.

replacement gas tank petcock also did not fit because of thread mismatch (original has fine threads - replacement was coarse threads) more bad xref info from sellers.

I installed clear line and new filter so i can fuel flow. I think its a fuel starve problem but I'm off to the dealer to be rescued.

(Note: i was doing this to help a young lady who had let it sit for a year.)

[zanetti2000]

I replaced the reed valves ($21) and that resolved the power problem. Scooter now does 40+ MPH.

The repair was relatively easy. reed valve (not just reeds) is located under the throttle body.