Time for a new auto bystarter

[MooseMax]

Good call, Zombie. There's no voltage going to the bystarter when the key is on.  It moves 4 mm when connected directly to the battery. 

I would think turning in the low-speed screw would compensate for the non-working bystarter, but it just seems to make it worse. 
Anyway, i can't make sense of the wiring, so i'd like to splice in the bystarter somewhere else.  Any recommendations where? 

Not sure if it matters, but one of the bystarter wires goes to a resistor.  The rest of the wiring diagram is on this page.

[MooseMax]

B&L - i ordered an iridium plug - thanks.  I actually had one before, but my shop thew it away and installed a regular NGK.  They didn't know what it was!   

I've watched a few youtube vids on adjusting valves, and it seems pretty straightforward. 

[zombie]

Way cool.

Your bystarter is AC voltage supplied. It has a pair of opposing diodes, and a resistor to reduce the voltage from 250Vac to 12v ac/dc.

What we're (you're) gonna do is eliminate all that slop/extra components, and go direct for 12Vdc.
You're gonna have to pick up a new +12V that is key switched. ANY +12 will do. Maybe the seat light? maybe the blinker power BEFORE the switch? Any 12V that turns on w/ the key.
The yellow wire from the bystarter goes to that +12, and the green wire will go to ANY easy to get ground. Add a ring terminal, and double it up on the starter motor? Maybe one of the green wires to the lights... Any ground.

My guess is the resistor or one of the diodes failed. It's not hard to sort that out but it is a weak link, and will fail again.

I'm glad you double checked. Oh yeah... The idle mix will compensate for either choke or no choke but not both. The choke adds a LOT of extra fuel. More than the pilot jet can pass on its own.

[BettinANDlosing]

Way cool.

Your bystarter is AC voltage supplied. It has a pair of opposing diodes, and a resistor to reduce the voltage from 250Vac to 12v ac/dc.

What we're (you're) gonna do is eliminate all that slop/extra components, and go direct for 12Vdc.
You're gonna have to pick up a new +12V that is key switched. ANY +12 will do. Maybe the seat light? maybe the blinker power BEFORE the switch? Any 12V that turns on w/ the key.
The yellow wire from the bystarter goes to that +12, and the green wire will go to ANY easy to get ground. Add a ring terminal, and double it up on the starter motor? Maybe one of the green wires to the lights... Any ground.

My guess is the resistor or one of the diodes failed. It's not hard to sort that out but it is a weak link, and will fail again.

I'm glad you double checked. Oh yeah... The idle mix will compensate for either choke or no choke but not both. The choke adds a LOT of extra fuel. More than the pilot jet can pass on its own.

This resistors are to make it so the bystarter turns off slower. And yeah you won't see 12v with key on because it only powers up when the engine is ruining. The best test is to fully warm your bike up with the seat off, then quickly take out the bystarter and see if it's down. I have seen your diodes and resistors go bad before so could be your problem. Check the carb warmer for 12v dc (the two wires going to the bottom of the float bowl). Or just for testing just run a wire with switch directly from the battery. If it was in my shop i would completely clean the carb before messing with anything else.

[zombie]

 "And yeah you won't see 12v with key on because it only powers up when the engine is ruining."

Wow... Yup!  You'd have to check w/ the bike running... 1/2 of Kymco is ac, and the other 1/2 of them are dc...

I was working the assumption it was a dc fired CDI bike but w/ an ac circuit firing the by starter...
In any event the bike would have to be started to show voltage.
My oversite.. 

Thanks B&L for spareing Moose from a death by many wires! I'd still check for voltage running...
Clean the carb. Then rake the lawn, and get us a couple cold ones... please.

[BettinANDlosing]

"And yeah you won't see 12v with key on because it only powers up when the engine is ruining."

Wow... Yup!  You'd have to check w/ the bike running... 1/2 of Kymco is ac, and the other 1/2 of them are dc...

I was working the assumption it was a dc fired CDI bike but w/ an ac circuit firing the by starter...
In any event the bike would have to be started to show voltage.
My oversite.. 

Thanks B&L for spareing Moose from a death by many wires! I'd still check for voltage running...
Clean the carb. Then rake the lawn, and get us a couple cold ones... please.

The CDI is DC but the bystarter circuit in most Kymcos is ac fed. Idk why they didn't just do a key on 12v lol. I've had those resistors go out and throw me on a loop diagnosing the problem. Hey zombie where you at in Florida? I'm going for the first time this week, Lakeland and Tallahassee.

[zombie]

Tallahassee is the closest "big city" to us. It's about an hour, and some from Carrabelle.

When are you coming? I have a buddy that owns a bar, and a condo right across the parking lot.

If you come to Fl, and we don't go get F'd up together I will curse your ancestors...

[BettinANDlosing]

I'm not sure when we're going to Tallahassee, and not sure what the car situation is.

[zombie]

Let me know what/when/where. If I leave now.... I'll be there Mon-Tues..

We gotta set sumptin' up.

[Stig / Major Tom]

Everything Zombie said.
That filter is toaste, toss the new one in if you haven't yet. The Spec is 2.5 turns out but I've always found they work better at around 3 turns out. In fact my B&W factory setting is 3 turns out, has the identical carb to a People 250, the S250 carb is slightly different. I thought you had an s250 because you were asking about s250 parts!! You should open the carb and do a deep clean, not all that much to screw up just take your time and remember where everything goes, or draw a picture or whatever helps you remember. I suspect the slow jet is clogged, you have to use a very very small wire to clean it. I use one strand off a shifter cable for vespa/ stella style scoot. Works great. Or you can buy a can of the carb clean juice and soak it in there overnight. Almost every problem like yours roots from a dirty carb. Once reason why carbs are "worse". IMO having to clean parts is WAYYYYYYYYYY better than buying new throttle bodies, injectors etc. Have you done other routine maint stuff? Make sure valves are at .04mm, changed plug? DPR7EIX worked great for my 250. Valves would make sense, if one is too tight it'll be WAYY too tight when really hot and cause poor performance. The P250 is a kinda tight to adjust the valves, not too bad. You have to take the valve cover off with a friend sitting on the bike to get enough room, then it's easy. If I were you I would order a NGK Iridium DPR7EIX and do the valves and clean the carb. I would be surprised if it needed more than that @ 10k KMs. I've seen customers with over 50,000km on their P250, great motor. My buddy also has a 2005 silver P250 which we replaced every last plastic panel and made it like new. Anyway keep us posted, that way we can all figure it out together yay!!!

MAN , THIS IS GREAT STUFF!
Like watching re-runs of "Gun Smoke" in German!!
Sign us, The Bosch EFI engineers in lab #16.
Hamburg Germany

[zombie]

Veee luvv der Germans. Zay are Veryyyyy schmart.  Und der Gunschmoke... Eeees' funny ya!

[Pablo.gyds03]

I know this post is pretty old but does anyone know where the resistor is located or if you have a picture of where it's mounted on the scooter? thanks!

[Pablo.gyds03]

I found it, its on the Same bracket as the Regulator/Rectifier just above the exhaust.