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crf250 valves

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Hey guys, I have a 2004 crf450 so I am normally in the 450 forum. I am selling the 450 because I dont want to deal with the valve problems. So I was just wondering if the crf250r's have valve troubles like the crf450's (frequent adjusting, replacing, hard starting, exc) Please let me know what you guys think. Thanks. :applause:

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I have never had valve problems on my 06 crf250r, I got to one hundred hours before the first adjustment, and 10 hours later when I put in new piston and rings, the intakes have not moved one bit from the .006 thou. and the exhausts haven't moved at all, except for a little bit on the right exhaust, not a problem at all.

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Hey guys, I have a 2004 crf450 so I am normally in the 450 forum. I am selling the 450 because I dont want to deal with the valve problems. So I was just wondering if the crf250r's have valve troubles like the crf450's (frequent adjusting, replacing, hard starting, exc) Please let me know what you guys think. Thanks. :applause:

they all take maitanence. but the x is a little better on valves

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The X cam is less agreesive in performance but the cam lobe / ramp design is harder on valves than the R

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Hey guys, I have a 2004 crf450 so I am normally in the 450 forum. I am selling the 450 because I dont want to deal with the valve problems. So I was just wondering if the crf250r's have valve troubles like the crf450's (frequent adjusting, replacing, hard starting, exc) Please let me know what you guys think. Thanks. :applause:

If you are trying to run from valve issues off a 450 to a 250,you are chasing your tail in the wrong direction.Break down and buy some RHC coated steel valves maybe a new head.You can do this for less than 700.00 bucks with 07 head.It's better then dumping 6K on a new bike.

450's should generally get longer valve life because your not squeezing em for all the power.With your 04 450 it's time to put a little back into it.Any thing is better than a new bike payment.:applause:

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Justin get a 250R like mine... You know you want too.

Take mine out for a spin anyway and see if you like it.

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I am still not sure yet Ryan. I want to see the difference between your x and your r.

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I dunno, I have heard that the 250's dont have the valves trouble like the 450's. I don't know if thats true, but I definately want to find out before I get another bike. Thanks for the info. :applause:

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so will an aftermarket cam like the crower eat your valves up or not???? I dont understand all of the valve issue's and needing to change the oil and piston so often. My 1000 went 35000 miles with only regular oil changes every 3000 and I rode the crap out of that bike. constantly popping it up and revving it too the moon and I never even thought about rebuilding it. Every body gets me so hyped up about my bike blowing up I find my self changing the oil in both sides everytime I go. Oil still looks brand new when im taking it out. My dealer told me it was horse shit and not to check my valves until the bike is making noise or is hard to start. Why cant they make the valve train just like the big street bikes?? they are light and super high revving and get alot of hp from a given displacement.

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so will an aftermarket cam like the crower eat your valves up or not???? I dont understand all of the valve issue's and needing to change the oil and piston so often. My 1000 went 35000 miles with only regular oil changes every 3000 and I rode the crap out of that bike. constantly popping it up and revving it too the moon and I never even thought about rebuilding it. Every body gets me so hyped up about my bike blowing up I find my self changing the oil in both sides everytime I go. Oil still looks brand new when im taking it out. My dealer told me it was horse shit and not to check my valves until the bike is making noise or is hard to start. Why cant they make the valve train just like the big street bikes?? they are light and super high revving and get alot of hp from a given displacement.

sport bikes dont get thrashed around in mud, knocked over, arent banging off the rev limiter most of hte time, and have a lot of air going through the radiators. They also hold a lot more than 700 ml of oil

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so will an aftermarket cam like the crower eat your valves up or not???? I dont understand all of the valve issue's and needing to change the oil and piston so often. My 1000 went 35000 miles with only regular oil changes every 3000 and I rode the crap out of that bike. constantly popping it up and revving it too the moon and I never even thought about rebuilding it. Every body gets me so hyped up about my bike blowing up I find my self changing the oil in both sides everytime I go. Oil still looks brand new when im taking it out. My dealer told me it was horse shit and not to check my valves until the bike is making noise or is hard to start. Why cant they make the valve train just like the big street bikes?? they are light and super high revving and get alot of hp from a given displacement.

Just like weather man said, and also these bikes are getting an excess of 2.3 HP per cubic inch, that would be the equivalent of having a 350ci truck getting over 800 horsepower... And they also rev to the moon, 13,140 rpms, is the limiter on 06 and down. not many things can last at those rates, w/out proper care and maintenance. They are designed for one porpuse, to be as competitive as possible, as stated in the front of the service manual.

Your piston is going up and down over 200 times a second and your valves are opening and shutting over 100 times a second, when you are revvin'

Don't worry about your bike blowing, just keep up with regular maintenance and you will be fine, you can stay at limiter for 10-15 seconds before it blows or any damage is done, so as a rule of thumb try and keep it under 7 seconds if needed.

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The cams in the curent dirt bikes also have more agresive seating velocities than the gsxrs and such causing the valves to where .also over years of working on motor cycles you would be suprized how many of the gsxrs and hondas i had seen with there steel intake valves eroding and loosing clearance all most all of the 1980 cb 750 hondas that got ran hard had some problem with there intakes they were usally leaking just enough that they wouldnt idle good and you could not sync the carbs worth a crap .

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