Need jetting help with XR100 please.

Hi, I (my son) have a '99 XR100, it has an uncorked stock muffler with homemade endcap. The modified muffler seemed to help it breathe a little better, but I have recently cut the mesh screen out of the airfilter cage, and am looking for advice on where to start with the jetting, as it is running a bit lean now. Stock main is a #96. I have fitted a Dynojet #98 I had lying around, but still feel I could go larger. Has anyone any suggestions on how large? I am at sea level, thanks, Chris. :)

If your trying to get rid of the bog that developed because it breathes better then try raising the needle (moving the clip to the bottom).

Check to see if the Dyno jet numbers are the same as Keihin.

I would go to around 100 to 105 and like minifig-phil said richen the needle. The small Kehin jets are a bit hard to get as most dealers cant work the Honda fische system and find them. Give me a PM if you problems. Have you opened up the airbox by taking out the snorkle etc? Also replace the stocky aircleaner element with a Unifilter.

Thanks minifig-phil and ACS, I will do the needle on the weekend, and have a play with some main jets as well. I have removed the airbox snorkel, and i'll order a Unifilter for it too, thanks again for the tips, Chris. :)

I ended up using the second clip pos' from the bottom on the needle, and a Keihin #102 MJ. Bike is way stronger, and rev's heaps more freely. Thanks again Phil and ACS, this is the sort of advice you just can't get anywhere else. TT RULES. :)

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