Question: 81 250, 2nd Stage Big bore kit, no instruction about tuning Carb.

[Adam250sx]

G'day, I had a stage 2 big bore kit (5.5mm) put in my 81 250R which makes it now 287CC. The problem is there was no instructions on how to tune the machine once the kit was installed. (Bought kit off Ebay) Right now I have put 3 tanks of fuel through the bike so I am pretty sure it is broken it. It starts fine, idles, I can rev it in netural, but when I put it into gear, it doesn't have much power. So when I go past 1/4 throttle to full throttle it has the same power. The powerban sometimes kicks in for a second or two then it just starts bogging again. I was wondering if anyone new the main jet size when you add a big bore kit and what else in the carb needs tuned. Any info would be much appericated.
Thanks
Adam

[350x'inNY]

What kind of carb, airfilter and exhaust are you using? You will probably need a larger carb. I think this is one of the reasons they say the Hondaline 300R kit is for the 83-84R's and not the 81-82R. I know the 300r kit comes with a larger jet, and physically it will fit in a 81-82R. The 300R motor I have looks to have a 85-86R carb on it, so for me to look at the jet would be useless unless you have the same carb.

Bruce

[81Rmachine]

It sounds like its runnin too rich take it out and get it in fifth gear full throttle while holding it full throttle very quickly snap the throttle back to about 3/4 and if it pulls harder and kind of catches when you snap it back that means its too lean but if it makes no difference its probably too rich. Best indicator is your spark plug if its chalky white its too lean and if its black its too rich. Its running perfect if its a light golden brown.

[team-red-rider]

this is 2 years old lol