I decided to risk my sanity and am now (since Aug!) the proud owner of an rs250 here in Malaysia. This is my first two smoker, and my garage/mechanic appears to be at his wits end as to how to fix it. He did the pistons, rings and gaskets to get the bike to run smoother, and though it did help, it does not appear to have fixed the fundamental issue. Guy keeps cleaning the carbs like somehow this time its going to make a difference (3x already!). I'm guessing thats not the problem....
The issue is that the bike appears to hesitate on throttle and have flat spots, but seems to be okay at higher revs. But after a good run at revs, she will bog down (seriously) after coming to a stop. It bogs down for a few minutes (during which time I'm limited to say 4k in rev range regardless of throttle position) and then after that she goes back to revving like a maniac (i.e. normal). Additionally, the exhaust appears to leave a lot of dark, thick oil in the can. Finally, I noticed there is incredible amounts of smoke when you first start up. Last issue is that it runs really hot.. I see the temp gauge over 100s, up to 104 regularly... Is that normal? After 100 it starts blinking which makes me think the fan should be kicking in at that point..
Here's my poor attempts at fixing/rationalizing : I suspect this has to do with the oil mixture the pump is putting into the engine. Separately, there is a little extended screw/adjuster which the previous owner set up to adjust the air/fuel mixture.. I gave that a twiddle (to the left - im guessing leaner air/fuel mixture) and took her for a spin, that appears to have helped, but still a lot of oil in the exhaust can. As for temp gauge, no ideas... Mechanic says its normal??!
So.. after hearing my rationale, anyone care to take a view as to what the heck the freakin problem is? I'm about to give up on two strokers and that would be a bad thing, coz the bike is fundamentally awesome. Low weight, good power, incredible handling, I really want to love her, I do!