I know the 02 didnt have the RC valve but is very similar to your 07. What all did you do to make it a bit more friendly ?
I have an ownership and may green plate the CR, we do trail riding as well as the MX track.
The only year Honda cr 125 that had the RC electronic valve was 04'.
The first thing that I would do to your 02' is bolt up an 05'-07' air boot.
Here is a list of the things I did to my 07' to make it more off road friendly. I wont mention guards as Im sure you have those. although I did use a TM designs chain guide from and 08 crf250 on the 125. that took about 5 min to make work and looks perfect.
1- 38mm Keihin pwk carb. The stock Mikuni carb is pretty much junk.I got my PWK off of ebay. Mine is from an 01' yz 250. Some of the pwk's are 90mm long(screw on tops) and some are 75mm( squareish top and the top is held on by 2 screws). Your 02' would want the 90mm screw on top PWK. The, I believe 03-07 cr's both 125 and 250's use a 75mm length carb. With that said you can just buy a PWK carb right from JD jetting, but I don't like his jetting specs for offroad. If you do buy a used carb the power jet has to be plugged. It takes about 5 minutes and some Quick Steel, or the correct size plug, I got mine froms Lowes hardware. I'll give you my jetting specs for here in upstste NY. The Needle is an NEDG form a late model Suzuki 250, 42 pilot and a 178 main. That jetting really smooths out the power and makes the bike much more friendly on the trails. With the Keihin carb the jetting is very flexable and easy to manipulate. I also have jetting for MX use that is different.
The next thing I did was put spacers in the exaust pipe, or you can weld them on to the exhaust spigot. I wound up with 11mm as about the best compromise. They do effect the topend somewhat, but they really work for improving lowend power and response. I made my own, but you can buy them from mxbonz.com I also have an FMF pipe that I tried them on ,but I like the stock pipe better.
Send the head out to get the squish set and bowl shaped. I had mine set to 1mm. That will still allow you to use pump gas. This mod also improved the lowend response quite a bit.
I use a 13-53 sprocket combo. Use a light weight steel(ironman) or an aluminum rear sprocket. I could actually feel the difference between a heavy steel sprocket and the lighter one.
Send the suspension to your place of choice and have at it. This has been a really fun and reliable bike to ride since I replaced the the stock carb for the PWK. I'm going to keep this bike for a while it's just sooo light weight and fun to ride compared to my Gasser.
