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Rev Limiter Question!

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Haven't been on here in a while! (Now on hardcoresledder as well)

But anyhow... So my buddies were riding a nice local sandy practice track, thats mostly hills and massive whoops, its actually as beat as it can get.

So now my other buddy came down and he was unbelievably fast around this track and I noticed he was rippin' of the rev 60 % of the time! Now my other friend said that that actually isnt the proper way to ride, and your so much faster if you just click up a gear! He said hes lucky the bike didnt blow up!

Now im asking you guys what you think! I know its not bad to do it every once in a while, but if your really hammering it why do it more, why not just shift?

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On a 450?? SHift!!!! Now need to be riding of the rev limiter. You will actually be making less power than at the power peak etc. Probably like 3-4hp less than at the power curves peak. Plus missing out on all the mid range torque. Just my 2cs'

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Rev limiter on a CRF450 is about 11,000 RPM. If you look at the dyno charts of a 450, they tend to hit peak power right around 8000-8500 RPM. Optimal point to shift @ WOT is around 9000 RPM for a stock bike.

There is no reason to be on the limiter with a 450. I mean yeah we all hit it occasionally (like when trying to muscle through some nasty mud), but just extra wear and tear being on it most of the time.

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Oh yes see thats what I thought! But another kid was doing the same, only on his 250f, which seemed to hit a lot quicker then the 450's. He was actually on it more, does it cange going from a 450 to a 250?

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I never come close to the rev limiter on my dirt bike as it really looses steam at higher revs. I keep the revs where the bike has the most power. Which I'm guess is from 3-8K.

My street bike is the opposite, and I'm constantly bouncing off the rev limiter with it. Well in first and second gear. Bounce off the rev limiter in any other gear and I'll be losing my license.

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Yes there is quite a diff between the 250f's and the 450's. You generally need to ride the 250's up near the top end of the power band. Kinda like a 2 stroke. And even though I dont agree with constantly hitting the rev limiter!! I can see it happening alot more often on a 250.

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Oh so the "peak power" is more towards the rev.. I dont know what it is on a 250f but yea now this makes since. But it seems like it was rode pinned through woops sections with a lot of clutch work in the corners... The kids really good to he spends a lot of time down at MTF

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He needs to work on his technique if hes spending most of his time on the limiter. He's making about 5HP less staying on the limiter rather than shifting and staying in the ~7500-8500 RPM range. He's running so high in the RPM range, he can probably run up another whole gear without loosing much if any acceleration.

EDIT: Actually, I just ran the numbers:

He can run two gears higher and STILL have an increase in torque to the rear wheel..and torque at the wheel directly affects acceleration. The engine is just loosing that much power so being high up in rev range.

Edited by Lead Head

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See I love the facts! I know every once in a while you have too but its funny how much faster you can really be if you shift... even though it may sound "cool & fast"

Now does it actually do any damage to the motor?

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See I love the facts! I know every once in a while you have too but its funny how much faster you can really be if you shift... even though it may sound "cool & fast"

Now does it actually do any damage to the motor?

There's nothing about the rev limiter that actually does damage to the engine - as that is what it is there for. To stop you from over-revving the engine.

The thing is though, you're running the engine about 3000-4000 RPM higher than you need to. It's just a ton of excessive wear on every part of the engine for less power.

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not only is running a motor on the rev limiter above the peak power and torque, but if you were to mistakenly downshift while on the rev limiter your likely gonna bend valves/break the motor. The rev limiter cuts ignition when you give it gas, but there is nothing to limit revs on deceleration.. if the rear wheel grabs on a downshift the motor WILL spin faster than the perscribed rev limit.

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So I really dont get why I see a ton of guys hammering it off the rev all the time then! Just doesnt make sense to me..

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So I really dont get why I see a ton of guys hammering it off the rev all the time then! Just doesnt make sense to me..

It sounds cool and makes you seem fast. :lol:

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they wanna join the Justin Barsha fan club.. that kid has mad skill, but is REAL hard on motors. There is an onboard vid floating around of him on a 250f. holy rev limiter Batman! LOL

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So I really dont get why I see a ton of guys hammering it off the rev all the time then! Just doesnt make sense to me..

you need to watch more professional racing, and listen to how they run the motor. If it was clearly the way to run a modern 4-stroke mx race bike, you would see more top riders bouncing the motor off the rev limiter. yea, they run the shit out of it, but they are not on the limiter all that often..

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