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Hi Ken,
I was interested in the Power up jetting kit for my son's 2003 Crf150f. Bike is stock with the exception of a K&N air filter and snorkel removed.
It has a bog when hitting the throttle quick and the power is kinda flat. I'm assuming this kit gives more fuel to help correct this. Also, I noticed it comes with 2 main jets a 108 & 115, is the 108 for stock & 115 for modified.
Thanks & Happy Holidays!

yes, our Power Up kit will improve your jetting. the two main jets are to provide range for both engine mods and/or altitude changes.

ken

Hi Ken,

I installed this kit on my sons 03 150f.
tried the 108 main 1st, 42 slow jet & power up needle in mid position. Definite inprovement over stock but still had bog with quick blips. Tried dif clip positions & adjusting fuel screw, no luck with bog. Went up to the 115 main jet and there was inprovement, adjusted fuel screw, better but still has bog but better. Left clip in mid position. What would help eliminate this bog, 45 slow jet? Thanks in advance for your help and anyone who jumps in.

Ken

if the bog is occurring on the stand ride it and see if there is bogging under normal riding conditions. if so, be specific about where the bog is occurring (off idle or mid-range or top end).

ken

The bog is happening off idle. All testing has been done on a warmed up riddin bike. The bog is worse when the bike is stationary and you blip the throttle. When riding the bike its not as bad.

Sorry, When riding the bike the bog happpens off idle as well.

if you have the fuel screw out to 2.25 turns out then go up one size on the pilot jet. keep in mind, these carbs do not have an accelerator pump so you won't get the kind of results you can achieve with an AP.

The kit came with a 42 pilot which I used, the next size up I can find is 45. Is that correct? No 43 or 44.
Also , will dropping the clip position help?

yes, that is correct a 45 is the next size. sounded like you tried different clip positions already but yes, it never hurts to try. keep in mind, even CRF250/450 with accelerator pumps will bog if the throttle is snapped too quickly. so, make sure your expectations are inline with what the designed capabilities are of this carb.

Ken, thanks for your help & insight.
The bike does perform much better than stock.
With stock jetting the power was flat and the only way you could pick the front end up was by slipping the clutch.
With the kit installed it pulls so much better and you can pick the front end up with just hitting the throttle.
Now I just have to fine tune it!

Thanks Again
Ken

great feedback and as always, happy to help.

ken