28mm oko running out of gas????

[guen84]

when im running around 35-40 mph for a while my scoot just turns off??? only think i can think of is the carbs running out of gas... ill pull over for a couple minutes, then be back on my way.. i am using the oil tank for extra gas tank and that does not have a petcock... hopefully someone can help me out or ill just have to cruz at 50mph all the time... also can anyone with a set up close to mine tell me what kinda mpg they are getting.. i know mileage is gonna go down with mods but im getting about 20 mpg.... my V8 F-150 almost gets better mpg. just wondering if somethings wrong. when ever i stop theres always a little drop of gas on the over flow. so im not sure if im losing gas when i ride or thats just gonna be my mpg.... thanks

[Bear45-70]

Carbs do NOT run out of fuel at part throttle, they run out of fuel at WOT. If they run out a part throttle you have NO chance of ever seeing WOT. I would suspect a heat related ignition issue first. Have you check for spark right after it dies?

[guen84]

Carbs do NOT run out of fuel at part throttle, they run out of fuel at WOT. If they run out a part throttle you have NO chance of ever seeing WOT. I would suspect a heat related ignition issue first. Have you check for spark right after it dies?

no i have not when it happens im always stuck on road side just trying to get going again.... are you saying that maybe im loosing spark? not really sure what your getting at? might be a dumb question but would drawing to much power from the scoot have anything to do with that or is ignition straight off the stator? im running a HID light and a rigged up oil temp gauge for cylinder head temp (dont laugh it works for $15.00).

[Bear45-70]

Carbs do NOT run out of fuel at part throttle, they run out of fuel at WOT. If they run out a part throttle you have NO chance of ever seeing WOT. I would suspect a heat related ignition issue first. Have you check for spark right after it dies?

no i have not when it happens im always stuck on road side just trying to get going again.... are you saying that maybe im loosing spark? not really sure what your getting at? might be a dumb question but would drawing to much power from the scoot have anything to do with that or is ignition straight off the stator? im running a HID light and a rigged up oil temp gauge for cylinder head temp (dont laugh it works for $15.00).

Running out of fuel is not like turning off the ignition key. The key kills it now, fuel starvation is a sputter-sputter type thing. No, too much power draw on the battery will not cause this. The ignition is totally separate from the battery and it's charging system.

[guen84]

Running out of fuel is not like turning off the ignition key. The key kills it now, fuel starvation is a sputter-sputter type thing. No, too much power draw on the battery will not cause this. The ignition is totally separate from the battery and it's charging system.

yes very true bear, never even thought of it that way.... definetly not running out of gas...its like i turned the key off in motion... so you got any ideas on this problem???

[Bear45-70]

Spark plug bad (cheap to replace with a new one)

bad coil

bad CDI

bad stator

bad pulse generator (ignition sensor)

Your problem will be that unless the component is hot it will likely test good.

[guen84]

Spark plug bad (cheap to replace with a new one)

bad coil

bad CDI

bad stator

bad pulse generator (ignition sensor)

Your problem will be that unless the component is hot it will likely test good.

is there any way to test these things??

[Trafficjamz]

what does your oil gauge read when these problems occur?

What does your plug look like?

Does this problem not happen if you go wot or just part throttle?

[bakaracer]

sure sounds like its heat seizing to me. the setup your running, if the compression is to high, it will run hot.

[spree-rider]

too small main jet. learned this one when i was running a uni.

[guen84]

what does your oil gauge read when these problems occur?

What does your plug look like?

Does this problem not happen if you go wot or just part throttle?

gauge reads about 210 spikes to about 260 at stop lights...
plug looks pretty good not perfect yet, still playing with jetting and tunning....
problem its has happened 4 times now 2 different accurances... around 35-40ish mph cruising so part throttle.. never happens when im WOT or even 3/4.... just runs around that speed...

[guen84]

sure sounds like its heat seizing to me. the setup your running, if the compression is to high, it will run hot.

compression is at 145 i believe.... im runnning 93 octane 32:1

[bakaracer]

so you have a cht gauge on your bike? what plug are you using?

[guen84]

yes like i said its make shift temp gauge it doesnt respond as fast as a true cht would but it gives cruising speeds...
im using NGK BR8HS

[bakaracer]

if your running a 48 pilot in a 28mm carb, its running lean down low so that will include your 1/2 throttle area. you should be running at least a 52 pilot if not 55. being that your make shift cht gauge is not quick enough, Im bet its not accurate either because 220 is pretty much a idle temp for thses engines. dont let the color of the plug fool you either. if your not doing a correct plug chop. you will never know how it really running. it can turn that color in a few seconds at idle if the plug is hot.