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mn519

91 mph on stock 06 yz450f!

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Only 3 hours on my new 06 and I ran her down the road side by side with a 04 CBR600 just to see what she has. I ran up on 92 before the rev limiter kicked in, holding her on the limiter for a few seconds was a steady 91 mph! That is just insane!:thumbsup:

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Only 3 hours on my new 06 and I ran her down the road side by side with a 04 CBR600 just to see what she has. I ran up on 92 before the rev limiter kicked in, holding her on the limiter for a few seconds was a steady 91 mph! That is just insane!:busted:

I didn't realize there was a rev limiter on the YZ? With my bike and a Dr.D , I have yet to reach any limit. It just never stops pulling in 5th and I've had it in the desert where it's wide open riding.

5th gear just never ends on my bike. :thumbsup: :thumbsup:

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The YZ450 is rev limited to 11,500 RPM. Most people don't run into it much because the power drops off rather sharply at around 10,500.

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Only 3 hours on my new 06 and I ran her down the road side by side with a 04 CBR600 just to see what she has. I ran up on 92 before the rev limiter kicked in, holding her on the limiter for a few seconds was a steady 91 mph! That is just insane!:thumbsup:

To really find out for sure, get a GPS and do the same thing....street bike spedometers are usually quite flattering, especially at higher speeds. Some are off as much as 10%.

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91 mph is a factual number..... Dirt Bike mag dyno'd the '07 and it pulled 91 mph, so thats the real deal. Amazing top speeds..... I think I have hit 5th once, and that was by accident LOL, I also hit the rev limit once, and that was also by accident.... LOL

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The numbers seem right to me. My '03 has been clocked at 87 running a 15/49.

The theoretical top speed at 11,500 is 96, and at 11,000 it's 92. Factor in wheel spin, even on pavement, and 91 seems completely believable if it actually hit the rev limit.

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The numbers seem right to me. My '03 has been clocked at 87 running a 15/49.

The theoretical top speed at 11,500 is 96, and at 11,000 it's 92. Factor in wheel spin, even on pavement, and 91 seems completely believable if it actually hit the rev limit.

Yeah it actually hit the limiter, it was pretty pronounced. I was side by side with the cbr looking at him when it hit and he heard it loud and clear also. When we got to the river(we were heading to jump in) his exact words were "you hit 92 as you hit the limiter, then it was a steady 91" the "steady 91" was a few seconds I just held it there fluttering. We were no more then a foot apart side by side so we were goin the exact same speed.

To the guy that commented earlier on the headshake. It doesnt bother me on tar, I used to race a rocket and have had bad headshake setting the front end down over 100mph when the front tire is not spinning anymore. Lets say it leaves a 10ft black mark with the front wheel and headshakes like a :thumbsup: sometimes, but I always knew when it would happen and could muscle it out. In the dirt is when I hate headshake, because I never know when to expect it, and it seems to be alot on this bike:mad:

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I think that I read in one of the 06 shootouts that the 06 yz450f and the 06 crf 450 both put out 50 hp and top out at 97mph. Not 100% sure so easy on the lashings.

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You're right about the horsepower :

http://www.thumpertalk.com/forum/showthread.php?p=2750635#post2750635

But the speeds are theoretical, "on paper" calculations based on gearing and wheel size at the rev limit ( I get 96.2 using a tire with a 13.25" rolling radius). In the real world, tires slip under the kind of load necessary to reach 90 mph, and with a knobby, even on pavement, you have to take off 5-10%. 90-92 is more like the truth.

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as far as i know a 250 2 smoker will only do 70mph flat out. the 450's are that much faster ?

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Yes, they are. The way it's geared overall, a 2005 YZ250 will produce rear wheel speeds of 77 @ 10K, and 85 @ 11K. Knock off 5 mph or more for tire slippage, and there you have it.

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