backfire issue

[hillbillyhpower]

just installed the hrc kit in my 08, valve clearance is good, adjusted carb as instructed in hrc manual. everytime i hit the button it backfires continues to turnover then fires. is this a simple carb adjustment? and if so what measures do i take to have this thing fire right up like with the stock cam

[Jason Hall]

Does It backfire out the exhaust or the carb? I'm sure the 08 has an accelerator pump. Try hitting the throttle 1 or 2 times to give It a little shot of fuel before you crank It. If It fires right up with a couple pumps It's lean & you either have the throttle held open to far with the big Idle screw, or the small hard to adjust fuel screw (the bottom one) Is'nt turned out far enough. If It Is backfiring out the exhaust then It's probly rich which I doubt. If thats the case you might have the fuel screw out too far along with the slide to low. I have seen alot with the FCR carbs that people have the Idle screw set up to high & the fuel screw not opened enough. This will cause Irratic & hanging Idle also.

One thing to remember Is your pilot jet Is a set size, but you can fine tune It's size slightly up & down with the fuel screw. You need to sync the opening under the slide (Idle Screw Big One) with the pilot jet by fine tuneing with the fuel screw (small one hard to adjust under carb). This Is kinda confusing to explain. I hope I did'nt confuse you to bad.