Derbi kit on a hobbit - runs but not well.

Emil Kniemel /

I probably bit off more than I can chew but here it goes. Decided to install my previously used 50cc gila derbi kit onto my basket pa50ii hobbit (the bearings were originally busted and it had a pa50i cylinder on it-- so i figured it was the best time to experiment). here are the specs:

-original hobbit case bored out to accept derbi kit, 12mm crank installed

-6mm studs (using original stud holes on cylinder and head)

-moby av7 intake with a 15mm SHA clone (runtong) - 68 jet

-derbi pp head (no decomp channel) sanded down for < 2mm squish, decomp is not hooked up

-one-way bearing

-derbi 6-roller + treats rumpus plate @ 16 grams

-new treatland replica belt

-hack weld pipe

it runs and idles (rather well) but is very slow. its also jetted super low (currently at 68) compared to what i think it should be (maybe more like 80) but will 4-stroke and foul a plug if i go up any higher.

it only hits about 32 mph but SHOULD be going over 40 pretty easily i think maybe closer to 50.

any ideas? now that i've typed it all out i think i should tune my variator more precisely and maybe throw a temp gauge on it. (edited)

Re: Derbi kit on a hobbit - runs but not well.

Timing? That's way slow. Stock PA50ii is faster

Re: Derbi kit on a hobbit - runs but not well.

Emil Kniemel /

Stock points with woodruff key. Point gap is within spec.

Re: Derbi kit on a hobbit - runs but not well.

Emil Kniemel /

Hmm.

-Dropped the weights to 12gs

-Re-positioned my rear wheel

-DOWN jetted to 66

and it runs better. It has finally stopped 4ting at WOT. Temp gauge says 330 max so far.

faster all around but didnt have my phone on me and decided to stop pissing off my neighbors.

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