Dong Fang DF 250 RTB Bobber Information

[axa]

Beats me! It looks that something was lost in translation!

About carbie: I think that some CV carbie would do better job (for everyday riding) than plans slider type with acceleration pump.

But, IMO, there is one big thing that limits you significantly - this pushrod design with only one lobe and, as you realized earlier, non existing tuning cams.

Everything else you've already done....

BTW, did you tried to measure compression (not compression ratio, which is anyway just arithmetic mean)? You know... gauge, hose, spark plug hole, cranking... and result in... what you use in your part of the world - PSIs? On dry and with few cc of oil inside cylinder?

As you can see, my English limits me a lot, so I would mention few things for you "to think about". I'm not regular in this thread, so I'm sorry if I missed some mods on your bike.

If you already experiment with low octane gasoline and increased compression, you could think about buying adjustable or programmable CDI unit. Those adjustable are available at "Aliexpress". It could be handy to have possibility to adjust ignition angle and smooth engine's running.

Another thing is oil cooler. There are some kits with engine head cover with oil inlet and outlet, set of hoses and radiator, and what is important, it is "bolt-on" solution.

I believe that adjustable ignition and oil cooler could, if not prevent, than at least reduce, engine surges you mentioned half a year ago.

lets take it over to the enthusiast thread.