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Which Cam

By Glydene,
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Glydene

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I have a 2005 250X and I have 11 hours on new piston, rings, inlet valves (steel) and springs.

I have an offer for a 2005 250R cam and a 2006 250R cam but which would be the advantages of both and which would be best.

Any help would be of help as I cant make up my mind which one to get.?

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CRF420X

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According to Rick the new cam profile for '06 250R provides increased high RPM power compared to the '05. I wouldn't spend a bunch of time thinking about it though unless you had changed out all the other parts in the engine that changed btwn '05 & '06 to match. They are usually small changes that effect the entire package and not just the cam. In short, you may not see that extra boost if you don't have the other parts (like the new '06 head).

I would think the difference would be hardly noticeable. Which one is the better deal? If all things were the same I would buy the '06. If not I would go with the cam that showed less wear followed by price.

http://www.rickramsey.net/CRF250Xr0506.htm

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condor74

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The 2005 cam has better low end power bit not as good top end power as the 2006 cam. Both are way better than the stock x cam in my opinion. Get which ever one you get a better deal on. Do the ccc mods and pink wire mod to take the most advantage of the new cam. The 2006 r cam is the best mod I have done.

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Codeman00

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I only have tried the 05R cam...only because I read that the 05R cam increased the power throughout the entire range (which I can happily confirm!!!) and the 06R cam loses a bit of low but has more high end. It's up to you but I vote for the 05R if you are looking for an upgrade and you want to keep your low end. I'm very happy and I haven't even pulled the pink wire yet.

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CRF420X

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Good posts but I'm still a little fuzzy there. Most are making statements about cams but I'm not sure if they are talking about actual dyno results, seat of the pants impressions or going by what they read about a cam.

If its dyno then its a no brainer.

If its seat of the pants I would be suspect to take it as gospel but would tend to agree

If its what they read about a cam it would all be suspect. For example, if an '06 cam makes better top end on a '06 head with an '06 piston.... does that mean you can expect to see the same improved top end performance with an '05 head and '05 piston. Thats the part I have always been unclear about. It may improve top end on all bikes but then again maybe not.

I think I can sum it up with a question or two for the TT masses.

You have two bikes that are of different years but virtually identical except that there was a big change in the cam profile and the way the head was ported between the two. And since its relevant, lets say the cam on the newer bike was suposed to provide enhanced top end performance.

Would you expect identical results if you swapped out cams between the two? Would you see enhanced top end performance on the older bike?

Then of course there is the old trade off demon.

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condor74

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Swapping to an R cam on an X bike will give you more top end power at the cost of low end power no matter which year cam you are using. It is my opinion that the amount you gain on the top end more than makes up for the what you lose on the bottom end. The 05 is the mildest of the R cams hince it takes away the least amount of bottom end power. That doesnt change no matter what the flow characteristics are of your head. If you have a better flowing head you will have more top end power over the head that does not flow as good. However the lower flow head may make more bottom end power. It is the old trade off as you mentioned.

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moto_x2005

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Good posts but I'm still a little fuzzy there. Most are making statements about cams but I'm not sure if they are talking about actual dyno results, seat of the pants impressions or going by what they read about a cam.

If its dyno then its a no brainer.

If its seat of the pants I would be suspect to take it as gospel but would tend to agree

If its what they read about a cam it would all be suspect. For example, if an '06 cam makes better top end on a '06 head with an '06 piston.... does that mean you can expect to see the same improved top end performance with an '05 head and '05 piston. Thats the part I have always been unclear about. It may improve top end on all bikes but then again maybe not.

I think I can sum it up with a question or two for the TT masses.

You have two bikes that are of different years but virtually identical except that there was a big change in the cam profile and the way the head was ported between the two. And since its relevant, lets say the cam on the newer bike was suposed to provide enhanced top end performance.

Would you expect identical results if you swapped out cams between the two? Would you see enhanced top end performance on the older bike?

Then of course there is the old trade off demon.

If you comparing both to an X then the whole powerband is improved, even tho the X has good bottom end the 05R cam will make that bottom end hit even more noticable, pistons are the same for both years but the head porting is not.. even if you threw just an 05/06R cam in a X you will see gains, if you throw a better head in with it then the gains will be even more.. the X cam is anemic period, out of the R cams in a a 250R the 05 cam is the most anemic but has the best bottom end.. guys like this 05R cam swap to the X because the gains are still there, you will have more top end and the bottom will still be there, this is a seat of the pants result and you will most likely see close to or the same results on a dyno.. if you want to go the extra step and put an R head, and HC piston in it with the usual X mods you will see a really good boost without affecting reliability.. I have my old 05R, 06R cam and a modded 08R cam (springs), if someone near me has a X it would be cool to drop them in to see what the gains are..

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TheGrouch

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If you comparing both to an X then the whole powerband is improved, even tho the X has good bottom end the 05R cam will make that bottom end hit even more noticable, pistons are the same for both years but the head porting is not.. even if you threw just an 05/06R cam in a X you will see gains, if you throw a better head in with it then the gains will be even more.. the X cam is anemic period, out of the R cams in a a 250R the 05 cam is the most anemic but has the best bottom end.. guys like this 05R cam swap to the X because the gains are still there, you will have more top end and the bottom will still be there, this is a seat of the pants result and you will most likely see close to or the same results on a dyno.. if you want to go the extra step and put an R head, and HC piston in it with the usual X mods you will see a really good boost without affecting reliability.. I have my old 05R, 06R cam and a modded 08R cam (springs), if someone near me has a X it would be cool to drop them in to see what the gains are..

Let me know if you want to part with the 05R cam at a reasonable price.

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Glydene

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Guys, thanks for all the info and advise, I decided on the 05R and should get the cam on Friday and may fit it over the weekend ready for our trip to France to do some trails next weekend.

I will let you all know how it goes ?

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