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'02 mods test...stage 1 Hotcam, '05 ignition, 12.5/1 piston

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I've been racing my '02 for a few months now, and while I've had plenty of motor to get holeshots and win against '05 and '06's, after riding my old '05 (with a stage 1 Hotcam, stock piston and WB carbon pro) back to back with my '02 I realized how down on power I was...to be honest it amazed me that I had been pulling holeshots in +30B against the newer bikes...with a 48 rear sprocket the '05 had more low end than the '02 did with a 50. Add to that the fact that the '05 carries each gear further and I should have been getting wasted. Mainly, I really did not like the 13/50 gearing on the '02 because it let 3rd rev out too fast, and required a much earlier shift than the 13/48 gearing on the '05. But putting a 48 on the stock '02 killed the low end...it's amazing how much more low end the newer bikes have when you directly compare them. So, I decided to do what it took to be able to pull 13/48 gearing and get my '02 to run like or better than a stock '05.

I already had the 12.5/1 piston in my '02, so the higher compression was taken care of. First I installed the stage 1 Hotcam in the '02, left the stock 13/50 gearing on it, grabbed a 48 to take with me and headed to the track. After the boring but necessary break in period I finally rode it like normal and was amazed at the difference...the stage 1 hotcam has to be the best bang per buck mod you can make to an '02...it's a much bigger difference than you get putting one in an '05. The low end was SO much stronger, and I was literally a gear higher everywhere...very nice. But now it went through 3rd way too fast, so back to the truck to put the 48 on. Before, the 13/48 had me clutching 2nd out of some tight corners on the stock '02...the low end was feeble. Now, I almost could not tell I dropped two teeth, the low end felt just like it did with the 50 and pulled 3rd out of almost any corner...it was amazing. And 3rd gear now pulled further up top like I wanted...this was a great mod.

I then installed an '05 ignition, and headed back to the track the next weekend. I probably should have installed it before the cam, because the change here was minimal, especially compared to the HUGE difference the cam made. It did seem a bit crisper down low, and revved out a tad further, but no big change. It's a slight improvement, but an improvement, and I'll keep it.

In the end, I have an old FMF TI exhaust, 12.5/1 piston, stage 1 Hotcam and the '05 ignition on my '02 now(I also have an '04 airbox on it), and even with the heavier flywheel the '02 had stock it is every bit the match of my '05 with the cam and WB exhaust. For anyone wanting to bring an older motor up to newer performance, a slight raise in compression and a stage 1 cam is a cheap way to get the old dog to run just as hard as the newer models. It does take away some of the 'easy to ride' factor the '02 had as it pulls harder, but for those racing seriously it's worth it. I expect to get every holeshot now! :thumbsup:

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You should put in an '05 air boot also. It will let it breath a little more up top. Fits in the '03 '04 air box with no mods & I think only cost around $25. The '05 boot has more of a bell shape inside where it starts to open up. :thumbsup:

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I'm adding the airboot next, just installing one piece at a time. On the flywheel though, I like the heavier one better. My '05 was more difficult to slide around flat hard corners with it's light flywheel, it lit up too easy...I like the combo of '05 power with a little more hookup that I have now, our summer tracks get baked and hard pretty quick.

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I have to totally agree with you. I also have an '02 and put in the hotcams and '04 ignition. The hotcams was amazing, but I can't tell much, if any, difference with the '04 ignition.

I recently purchased an '06 CRF450 and it has even more power than my '02, which must be the camshaft, ignition and increased compression. I have installed a hotcams in my '06 to see if it makes a difference over stock, but have yet to ride it. I am hoping it will give the ’06 just a little more low end grunt.

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Brandon you should try and 05-06 CRF250 CDI. It is more aggressive than any of the 450's and you will notice the difference somewhat in the bottom but it give a nice boost to the mid-range and top. 3rd & 4th become very usable and revable.....

theDogger

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Do you have to get the 05-06 CRF250 CDI from a dealer and how much is it? Is it the same on the 05-06 450?

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Look on Ebay or ask guys in the CRF250R forum for the CDI's. They make a very noticeable mid-top end improvement. I need to create a sticky at the top of the forum on this.

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Do you have to get the 05-06 CRF250 CDI from a dealer and how much is it? Is it the same on the 05-06 450?

Check eBay they are always going for about $75 shipped.A CRF250r 04-06 will work. Its a great mod by itself.

The ignition curve is more aggressive than the CRF450r 02-06. Do a search and you will find plenty of posts...

theDogger

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You should just slap an RHC ported head on your '02, and get the RHC carb mod, and your '02 would absolutely spank any '06! :thumbsup:

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Thanks for the info, i also have a 02 CRF450 I just got so I am watching this thread for power gain possibilities.

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You should just slap an RHC ported head on your '02, and get the RHC carb mod, and your '02 would absolutely spank any '06! :thumbsup:

Yeah, and it would spank me in 2 laps! More than my conditioning can handle.

On the 250 CDI, my concern would be having the rev limiter at 13,000+...seems like an easy way to blow a motor during a panic rev or stretching a gear into a corner. Do you guys not worry about over revving it ever? An extra 2,000 rpms is a lot, how do you insure you keep it below 11,700 or so? If it's just by feel, I don't think that's for me.

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On the 250 CDI, my concern would be having the rev limiter at 13,000+...seems like an easy way to blow a motor during a panic rev or stretching a gear into a corner. Do you guys not worry about over revving it ever? An extra 2,000 rpms is a lot, how do you insure you keep it below 11,700 or so? If it's just by feel, I don't think that's for me.

Good point. RPM kills 4 strokes. I've seen too many baseball size holes in the front of the cases lately. That repair bill is steep, but I'm more concerned with me if that happens on a big jump face.

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Yeah, and it would spank me in 2 laps! More than my conditioning can handle.

On the 250 CDI, my concern would be having the rev limiter at 13,000+...seems like an easy way to blow a motor during a panic rev or stretching a gear into a corner. Do you guys not worry about over revving it ever? An extra 2,000 rpms is a lot, how do you insure you keep it below 11,700 or so? If it's just by feel, I don't think that's for me.

Even with the rev limiter at 11,2 Ive seen my tattle tale register 12.8 from a massive panic rev....Bumping that to 13500 or something sounds risky...

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did u rejet with the stage 1 cam if so did u have to do the needle main pilot leak or what? im going to put a stage 1 on my o2 and was wondering what all else i have to buy for the carb?

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