Ok I have a 95 honda cbr 600 f3 I ordered a six sigma jet kit. Ok I bought the bike for 500 which was too much. Anyway it had 132 main jets all the way across and 38 pilot jets. It has an k and N air filter and 2 Bros Exhaust. Not sure how it ran before jet kit but I'm sure 132 all the way is not stock? Service manual doesn't say. I have shimmed the needle jet with 2 shims, 42 pilot jets and 142.5 on 1 and 4 and 140 on 2 and 3. Bike hangs up in the rpms and takes a minute before it will return if it even does. It does this at idle once u blip the throttle and when u engage the clutch while riding. Stays at 3000. And also does not wanna idle. I have tried adjusting fuel mixture screw to 2.5 turns out like sigma suggested nothing, went all the way in to 1 turn out still no change. Checked for vacumn leaks no leaks? Could this be from the float bowls sticking? Or are the Jets way to big? Really confused and not sure what to do. I have the carbs off the bike as of now. Thinking about going back the way it was when I bought it. Any advice would be appreciated thanks.

 

I doubt this would help your problem but the bigger jets go to cylinders 2 & 3. I'd give the carbs a super duper cleaning and go back to stock jetting and adjustments. Is your exhaust just a slip on muffler with stock header or is it a full Two Bros system?

 

Yea stock headers slipon exhaust. Well the jet kit made an error then. Bc it clearly says 142.5 in 1 and 4 and 140 on 2 and 3. It had 132 all the way across? Idk....


​​​​​​​QUOTE=coalminer frank;1301697]I doubt this would help your problem but the bigger jets go to cylinders 2 & 3. I'd give the carbs a super duper cleaning and go back to stock jetting and adjustments. Is your exhaust just a slip on muffler with stock header or is it a full Two Bros system?[/QUOTE]

 

The theory is cylinders 2 & 3 run hotter because they're sandwiched inbetween the other two. So they can take a little more fuel than 1 & 4 and the extra fuel cools those cylinders a little. Generally speaking a lean mixture runs hot, rich mixture runs cool. Also a slip on muffler doesnt do a whole lot for performance if any at all. It probably helps more because its lighter than the stock muffler than any horsepower gain if any at all.

 

Makes perfect sense. I'll know if the changes I've made work by lunch tomorrow. If not back off again. I put the original pilot jets back in which were 38s the jet kit were 42s. So I'll be running 142.5 on 2 and 3 and 140 on 1 and 4. With 38 p jets. And 2 shims on needle. Also 2 1/4 turns out on fuel screw







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I'm looking forward to your results. I have a 96 that I paid twice as much as you for :-)

My bike idles a little rough and hangs on the blip. It does pull hard!