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Correct me if I'm wrong-Rev Limiter

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I understand every aspect of the rev limiter. It's purpose, everything. Now here's what I want to know. They say...yes say...that hitting the rev limiter can cause pre-mature valve wear/recession. Now that may be true, hitting the rev limiter every race may cause it. But how and why does anyone do it in the first place? I have all the power I need in the mid-RPM range. Even if I did ride the limiter, theres not that much power there. So why do most people do it?

Just curious-

CRF250AWP

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Looking at the dyno curve provided by KLX300A5L, you're right. According to the gear ratios posted on Rick Ramsey's site, you'll put the highest average power to the ground by shifting from 1st to 2nd gear at around 12,000 rpm. First to second drops engine RPM (ideal conditions, perfect traction, etc.) by about 19%. BUT, that's not the whole story.

I ride an '05 X and it turns out that this past weekend, we had a ride area that involved a 50 - 75 foot sandy straight, followed by a moderate sized sand jump, then a steep climb up a sandy hill. When accelerating on the straight, judging by RPM feel, I should have shifted from 3rd to 4th right at the face of the jump, but this is a dangerous proposition as you'll know if you've ever accidentally missed a shift on the face of a jump. I tried short shifting before the jump, but the engine fell off the power curve noticeably. I seemed to get the best times by over revving in 3rd gear until I cleared the jump, shifting into 4th in the air, and then climbing the hill in 4th. I was able to keep my overall momentum and acceleration up by over revving past the peak power range. The more aggressively I ride, the more I find situations like this where I need to make a call between over rev and short shifting. Just my opinion.

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Well for one instance, when you land off a jump sometimes it is neccesary to hold the throttle wide open before you land so you can clear the next obstacle, or just so your up in the RPM range.

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i no on my yz250f im usally in the high Rpms in my dist tracks. but on these 2 tracks im bouncing off the revlimiter in 4th.... is it a bad thing i dont think so thats why there is a rev limiter

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I'm just saying in general, yeah when I'm about to land I hit it once or twice. But people talk about being on the rev limiter the whole race. And what about that mod you do to the X's...the pink wire or something? If you have power where you want it, why modify the limiter so you can just keep reving?

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hahaha, good point CRF250AMP 😢

those people must be -> 😢😢

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you must have a stock bike. i have a 2005 CRF250R with a 05 white brothers aluminum pro and my bike pulls past the limiter it has just as much power on top as it does in the middle or bottom. that bike rips. i ride it hard in races and have no oil or valve problems yet. this bike decimates all!!!!

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you must have a stock bike. i have a 2005 CRF250R with a 05 white brothers aluminum pro and my bike pulls past the limiter it has just as much power on top as it does in the middle or bottom. that bike rips. i ride it hard in races and have no oil or valve problems yet. this bike decimates all!!!!

How can your bike pull PAST the limiter?? I promise you that you are dropping at least 5 to 8hp from peak to the limiter with your exhaust! Tdub

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Being on the limiter all race... That is usually a fish story....exaggeration... We ride little MX but alot of GNCC Style races. Most of the Top 125 guys ride their bike with little movement of the throttle it is ON or OFF. Most guys getting on a 250R/X are from that school. The 2 strokes like to be over revved to keep the power drop to a minimum. My son said the CRF wants to be shifted more. For most good MX/SX guys that know their track they will tweek the gearing/tuning to get maximum corner to corner rev out and minimize pinging that limiter alot. Running offroad that cannot be done as the track has to may variables. Changing our riding stlye a bit is harder to adapt to than anything else. Our pink wire is on a switch for now as we started to practice with it and without it. The bike sounds better but lap times are not much better. Junior said with the extra revs he likes it in some places since if he short shifts there is not enough power to get through the section and if he waits to shift into the power you get way too much speed just before you have to slow and turn. Now it's downshift or clutch it to death. Bottom line the CRF is just another balancing act like the 125 in some ways but the new found torque is another issue.. Maybe that big bore CRf may have merit....

As for me when I trail ride it or push at my race pace the bike hits the limiter only from my lazines to shift because that lil 4 stroker pulls so nice and I am a heavy guy.

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when riding in sand you want to keep the rear wheel spinning, if you're tapped in 3rd or 4th and you upshift its gonna take awhile for the engine to build momentum. Being a 2-stroke rider, Im used to overrevving the guts out of my bikes, but when i ride my friends 250F, i can feel the meat of the power and know not to overrevv.

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250f's are still making all of their power up high, not in the mid or bottom, just look at the dyno charts, all the power is up high, if everyone could short shift we probably wouldn't be as fast and wouldn't have to worry about any bike maintance.

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