Dr180 & scorpion

Hi, having spent the evening trawling through previous posts I now feel more than a little confused…

I have a PX125 Disk to which the previous owner has fitted a DR180 kit, when I bought the bike it was running really poor, very spluttery and reaching a maximum of 55mph. I stuck on a Scorpion pipe and looked at the jetting, it had a 108 in the stndard autolube carb… Was this to low could this have done damage? I have tried a variety of jets from the 108 to a 118 all to varying sucsess, some offer better pick up from go some help in the miid range, but none seem to release what i feel should be the true power.
At present i have a 116 in and i havn’t been near the timing… Should I? i also noticed the carb seem to „spray“ fuel, is this normal?

Any help or advice would be most gratefully recieved.[:@]

Anyone… please!!!


to me it seams 118 it is too big, I personally will try going a little leaner if you are using the standard 20 carb.

And try to replace the BE5 mixer tube with a BE4 and put a next bigger slow jet if not you could size if you keep for long time the gas closed and engine running like running down from a hill.

You should check the timing, the DR is sensitive to it and you can size if it is more advanced then 18°. So strobo it at 17° - 18°.

Where the carb spray fuel? It is when you take the air filter out that you see spraying some fuel out it is blow back it is normal.

And fit a correct spark: NGK B9HS or Bosch W3AC