70cc kit, vm20, techno boss. Idles fine, dies when throttled

Hey! I've been trying to troubleshoot my kitted tomos a35 since February :( have still not been able to get my ped cruising.

I've tried upjetting in attempts to 4 stroke it, checked for air leakage (there is none), and I still cant get it to throttle at high rpms without the engine slowly puttering out/ dying.

When choking the carb, the bike performs more normally, but engine dies eventually. Carb needle is on the richest setting. Also, idle jet is on 17.5. The main jets dont seem to make a difference since the engine dies if I apply more than 1/4 turn of throttle.

HOWEVER. The tomos idles perfectly

Here is the list of the aftermarket parts I am using:

Exhaust:

https://www.treatland.tv/ProductDetails.asp?ProductCode=tomos-tecno-boss-chrome

Cylinder Kit/Carb Bundle:

https://www.treatland.tv/ProductDetails.asp?ProductCode=tomos-a35-party-alukit

Individual Pieces:

Cylinder:

https://www.treatland.tv/tomos-a35-alukit-p/tomos-45mm-alukit-70cc-kit.htm

Head:

https://www.treatland.tv/tomos-moped-70cc-high-compression-head-p/tomos-70cc-head-moped-targa.htm

Carb:

https://www.treatland.tv/mikuni-20mm-carburetor-p/mikuni-20mm-vm.htm

Intake:

https://www.treatland.tv/WEAK-ENDS-intake-p/weak-ends-tomos-intake.htm

Reeds: (I forget which one I ended up leaving installed)

https://www.treatland.tv/malossi-VL1-carbonio-carbon-fiber-reed-block-p/malossi-white-reed-carbonio.htm

or

https://www.treatland.tv/ProductDetails.asp?ProductCode=puch-polini-reed-213.0017 (edited)

Re: 70cc kit, vm20, techno boss. Idles fine, dies when throttled

Re: 70cc kit, vm20, techno boss. Idles fine, dies when throttled

Great great diagram. thank you- will see if totally readjusting pilot system screws will fix my problem...

Could my exhaust combination with the 70cc kit be a problem? (edited)

Re: 70cc kit, vm20, techno boss. Idles fine, dies when throttled

Should be fine with that exhaust.

Try a skinnier needle. You can even try running it without a main jet to see if it 4 strokes.

Re: 70cc kit, vm20, techno boss. Idles fine, dies when throttled

Great news on the exhaust...

Where do I find a non-stock needle for the vm-20? I did some searching, no results :(

I am definitely getting some fuel starvation issues. Could my needle be sticking?

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