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CRF250X modifications

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I have a 2006 CRF250X that i want to get more mid range power out of.

I've been reading that dropping an 04 or 06 R cam in along with changing the head pipe from an R would give me more mid range.

I purchased a head pipe from an 06 CRF250R but it appears to be about 3 to 4" shorter than my X pipe. Is that correct? do i just move the Can up to connect to it (that doesn't seem right).

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check these links out one is the artical and the other is the pics. Look at the graphs, they show the dyno for the x cam, pipe, exhaust and r cam, with x pipe and x exhaust with no baffle and then different exhaust. on all graphs the r cam with the x pipe, x exhaust with no baffle is about the best with the exception of top end. Study them some and they become easy to read. I have a 06x with a 05 r cam, 07 r head, 08 r piston, and the x head pipe and exhaust with no baffle and after jetting it a good bit richer it runs great. I thought about a differant exhaust but as good as it run and sound after seeing the dynos i decide to stay with the x exhaust.

http://www.dirtrider.com/reviews/dirt_bike/141_0409_honda_crf250x_hop/photo_14.html

http://www.dirtrider.com/reviews/dirt_bike/141_0409_honda_crf250x_hop/index.html

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I bought my 06X and had them put on a full R exhaust system. I added a Hot Cam, JD jetting and a Loudmouth air intake with CCC recommended air box mod. Revved great, lots of top end but ya had to ride it like a 125 2 stroke (keep it revving and fan the clutch) Out of curiosity I switched to the full OEM X exhaust with modified baffle while I repacked the R can. Huge difference. Pulls like a tractor and is much easier to ride in all types of conditions. It still has about the same top end just takes a little longer to get there. Bottom line ...anyone want to buy a R system?

ST O.D.

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I have a 2006 CRF250X that i want to get more mid range power out of.

I've been reading that dropping an 04 or 06 R cam in along with changing the head pipe from an R would give me more mid range.

I purchased a head pipe from an 06 CRF250R but it appears to be about 3 to 4" shorter than my X pipe. Is that correct? do i just move the Can up to connect to it (that doesn't seem right).

If you're wanting to use a head pipe from the R model it must be from a 04-05 only. Honda switched to the twin pipe system on the 06-09 R's which required a shorter head pipe than the 04-05R's and 04-present X's.

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R headpipe used with the stock X small diameter tip (drilled or not) doesn't kill the lowend much if any, tucks in a lot lot better too,

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Some say the 05 r cam is the best compermise between top and bottom. Doesn't hit too hard off the bottom and not to weak off the bottom and also has good topend. Maybe not as much top as a hot cam or newer r came but still good top and bottom with great mid.

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The 05 r cam gives good low and mid range rpm improvments IMO with the emphasis being in the mid range, its also slightly better in the higher rpm ranges than the stage 1 hot cam.

BTW I have an 05 r cam thats in great shape I want to sell if anyone is interested.

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thanks for all the input. So it looks like i need throw the 06 R head pipe back on ebay and get an 04 or 05.

Also just to make sure I'm asking for the right thing. I do all trail riding no track. I'm happy with the low end but when i'm cruising along in 3 or 4 gear about half throttle and need to pull the front end up it just doesn't have the power. I have the JD jetting kit and open airbox mods done already and they helped alot but I want more wheelie response at half throttle.

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The 05 r cam gives good low and mid range rpm improvments IMO with the emphasis being in the mid range, its also slightly better in the higher rpm ranges than the stage 1 hot cam.

BTW I have an 05 r cam thats in great shape I want to sell if anyone is interested.

How much are you asking for the cam?

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Hope its ok to respond here, $100. plus postage and youll need to transfer your decompressor and bearing on that side

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If i'm wrong someone please chime in, if you want to pick the front tire up in 4th gear just by twisting the throttle you are asking alot. Other people may hay a 250x that can pick the front tire up in forth just by twisting the throttle but mine will not.

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just to be alittle more specific imo picking the front tire up and doing a fourth gear wheelie are two different things. With our bike picking the tire up to clear a hole or miss an edge is not to difficult if you twist the throttle and give the bars a pull, as long as you have some traction. The gearing should make a noticeable difference here, I think if your running 13/51 you could-if you wanted to-do fourth gear wheelies. We run 13/48

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oh yea mine will get the tire up to clear a small tree or so if i blip the

throttle and pull the bars but it will not hold it for long. I miss understood.

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I also have a 250x, but whenever i think about trying to gain power, i better think about migrating to 450x.

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So let me get this straight the "best" way to go is an 05' R Cam?...Before model year 06' header?...I already have the air box opened and diffuser drilled out and a re-jet...If I were to get the header and cam would I need to re- jet and also how complicated is it to switch out the Cams?...Any help would be great!

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I'm picking up my new X tommrow. I already found an 06R header pipe and muffler, I'm gonna pull the pink wire, and do the airbox mod. Am I on the right track and am I gonna need to change out the main after all that?! If so, to what? 50-55? Is there anyother quick and easy upgraded mods I'm missing?

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So let me get this straight the "best" way to go is an 05' R Cam?...Before model year 06' header?...I already have the air box opened and diffuser drilled out and a re-jet...If I were to get the header and cam would I need to re- jet and also how complicated is it to switch out the Cams?...Any help would be great!

The r cam is a good way to get a bit more power out of your bike, the 04,05 and 06 r cams are drop in cams not needing different, specific valve springs to work with them. The 07 and up r cams need to have the right valve springs and retainers when used.

You would likely need to rejet if you did these mods.

Here is a link that shows how to check and reshim valves, which is the same thing that is needed if you replace the cam. Its a good how to with pics.

http://www.thumpertalk.com/forum/showthread.php?t=179775

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So it looks like i need throw the 06 R head pipe back on ebay and get an 04 or 05. I do all trail riding no track. I'm happy with the low end but when i'm cruising along in 3 or 4 gear about half throttle and need to pull the front end up it just doesn't have the power. I have the JD jetting kit and open airbox mods done already and they helped alot but I want more wheelie response at half throttle.

You will be dissapointed I think, mine has ccc modswith 05R cam but using X header and 13.5:1 piston and it likes to rev and will lift the front a bit more as it comes on in the mid but it looses quite a bit of botom end. Not so good for trail riding. My mates sons bike with a hotcams S1 and R muffler kills mine for low and mid.

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You will be dissapointed I think, mine has ccc modswith 05R cam but using X header and 13.5:1 piston and it likes to rev and will lift the front a bit more as it comes on in the mid but it looses quite a bit of botom end. Not so good for trail riding. My mates sons bike with a hotcams S1 and R muffler kills mine for low and mid.

Why dont migrate to a 450x? I do trailriding too, at the begining i was using a 450R and wow! lot of power, the bad, it got hotttteer every difficult part on low speed, so i decided to migrate to a 250x because couldn't find any 450x on sale. But... the difference is 200cc its a lot. I did the jd and open airbox, also a megabomb and a power core. Not that much of a difference. My old 2002 450r lift almost both front and rear tire in 4rth gear lol very powerfull.

So ill be using one year the 250x and after that ill start looking for a 450x.

So the mod's to the 250x im not so sure they worth the money.

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I understand. I race SORCS events and ride with my buddies that are B class riders. They are fast as hell. But on this 250x its so easy to ride, and feels so plush and good through the tight, rough, choppy trails that I really don't need tons of power. I can ride the damn thing way faster than my rmz450 thru the woods!!! Even faster than my kxf250!! The bike just handles so well, you don't need 450 power to go fast. This thing pulls up any hill, runs with any other bikes in the woods and doesn't beat me up or tire me out! Most people can't even use the 250 to its full potential in the woods, much less a 450. Its all about handling, suspension giving you the confidence to put the hammer down on the worst of trails and with this bike, it does that for you! I did just order a Rekluse for my 250x, I'll do the airbox and pink wire mod and order a muffler. With all that, I won't need anything else, the bike has plenty and just handles like a dream. I know RaceTech says its under sprung for my weight, but it actually feels really really good in the woods, so i won't even invest in springs til later on when I got extra $$. This bike is ready and able right out of the box. Learn to ride, and you don't need to spend 1000s to gain a few hp lol

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