[Gone Riding]

I was wondering what I can do to get a little more power out of a 2005 CRF100 without spending a lot of money in it.

[oldtimer]

Best bang for your buck will always be increasing airflow and getting it jetted spot on. That bike is very similar to the 80 my son has. Maybe get a few of those air box vents and cut them in near the top of the box. Replace the stock filter with a higher flow unit. Take the baffle out and drill 4 or 6 big holes in the shaft. Then pick up at least on size bigger pilot jet a handful of bigger main jets. Then armed with this guide --> http://crfsonly.com/forum/viewtopic.php?t=3959 (just scroll down to the jetting trouble shooting section) and go for it!

The vents I was talking about --> http://crfsonly.com/catalog/product_inf ... ts_id/1348

[Gone Riding]

Take the baffle out and drill 4 or 6 big holes in the shaft

You don't leave it out?

Thanks for the great info. I will be doing it to the bike soon.

How high did you go with you main jet?

[oldtimer]

I have not done my sons 80 yet so I cant get really specific on the numbers. It’s his first year and he can’t use all it has in choked up form.
I’ll dig out his manual tonight (as it’s for the 80 and 100) and tell you what the stock main and pilot are.

On my 230 I did not remove the baffle. Nothing wrong with doing it however... I did drill the hell out of it to increase the airflow but still have the stock appearance. My local riding club is anal about noise and modifying. We are in Canada and I guess we are all supposed to be tree huggers???
It’s a perception thing leaving it in as I look like the good citizen but still improve performance.

[oldtimer]

The stock main is a 98 and the stock pilot is a 35. Just ask for the next size up of pilot and skip the next on the main and get 3 or 4 after that. They are a few bucks each. You can buy Keihin rather than Honda brand. Keihin is half the price and they are the actual manufacturer for Honda.

This will work even with the pipe you talking about in the other thread. The pipe may come with a larger jet but the jet will be sized for all conditions the same but the new pipe. They will not have factored in a higher flow intake.

[crf100rider21]

i cannot seem to find any of the jets that cr250oldtimer was talking about can you please tell me were to get them i found the vent caps will that help if i have a stock air filter

[spyke999]

Take the baffle out and drill 4 or 6 big holes in the shaft

You don't leave it out?

It's tough to keep out of trouble with baffles out. Unless you ride on a track or offroad, or just really want to make neighbours mad ( ) i suggest keeping them on.