crf100f bogs when you hit it hard

ok i know everyone says its jetting but im not buyin it so im searching for a defect i think i have a cloged passage to my main jet there are two passages feeding the jets on my carb i believe i should be able to fish a wire all the way through the one ending in the larger jet hole but i cannot because the needle jet (brass fitting the needle passes through (pressed into carb casting) is blocking 98% of the end of the passage ........looking into the bore where large jet screws in i see a brass fitting inbetween the side of the bore and that fitting i see the end of my wire but just barely ??????????????isnt that a problam??????????

the wire is being inserted at the begining of the passage (a brass tube) at back of carb the passage ends where it should feed the main jet isnt there supposed to b a clear hole here

I bought my wife a brand new (zero time/zero miles) 09 CRF100F from a local Honda dealership. It was very hard to start, and bogged at low idle and/or with slight throttle input. I checked the valves and they were factory perfect. Pulled the carb, cleaned it, and raised the clip on the needle. Works great. Cranks on the first or second kick consistently, does not bog at low or high RPM when inducing throttle.


I did not modify the air box, and did not remove the spark arrestor.


Sounds like the same jetting issue I had. Check your clip position in the carb and let us know where it is located. If your bike don't have grooved rings to adjust (raise) the clip, you can install a small (tiny) flat washer below the clip/spring which will serve the same purpose. Works great and will save you some money. On the other hand, if your carb has the grooved needle you can simply adjust the clip. However, we need to know the current position of the clip to provide you with the best advise. 


Good luck.













If you 'whack' the throttle of even a perfectly jetted crf100, it will bog, because that bike does not have a pumper carb, and, you would never do that riding.

trying the clip now

krannie i wack the throttle before every jump its called pre loading or setting up if the bike bogs youre at the mercy of the dirt

i have the adjustable needle its set in the middle

my instincts say bury the clip for more gas?

nice plane falcon1 that a cessna


burried the needle clip made a huge difference still has a little bog with rpid throttle movement very hard to stall it with the throttle now thnk im ready for a differnt jet now

still wish i knew for sure that blocked passage wassnt an issue??????????????

If you 'whack' the throttle of even a perfectly jetted crf100, it will bog, because that bike does not have a pumper carb, and, you would never do that riding.




That's not completely accurate.


If that carb is jetted/adjusted properly, and the clip is set to the correct position there will be very little "to no" bog when inducing throttle. My wife's CRF100F does not bog at all on the bottom or top end. Very crisp/responsive to throttle input.


It's a blast to ride.



nice plane falcon1 that a cessna




That's correct. It's a Cessna 206 in the background. 


Keep playing with the clip setting until you get most (or all) of the bog out when you induce throttle input. You can also buy a new jet kit for that bike that will bring it to life.. if you decide to change the jets, then you can open up the air box and remove the spark arrestor for overall enhanced performance. 


Let us know if you get the bike running better by adjusting the needle clip.



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