Rev Xtend feature?

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Jan 11, 2010 | 10:19 PM

#11

Mountainkowboy

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From: Anywhere we stop

Thanks for the info.

Jan 23, 2010 | 08:35 PM

#12

oneillto1

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From: Lakeland, Florida

Just another confirmation of previous posts. Since my engine build (08 Ultra), I've been revving the motor a lot more. I have also noticed the tach needle stops just above 5,000, but continues to rev to redline. Needless to say, I've hit the rev limiter a few times!!

Jan 23, 2010 | 08:46 PM

#13

harleytuner

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From: Fredericksburg, Va.

The rev limiter the ECU uses runs off the tach, so in order for PC to use rev x-tend the had to confuse the ECU to think that the engine isn't hitting the stock 5500 limit, so PC interupts the tach signal and stops the tach at 5000 - 5100 RPM's and takes over the limit. It's good in the fact that you can get higher RPM's but it sucks for racing or serious performance riding because you don't really know exactly where you are untill you hit the limit. By that time you are a split second late in shifting. no big deal unless you are racing or at the drag strip or something.

Jan 23, 2010 | 09:02 PM

#14

fuelmoto

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From: Little Chute, WI

Quote:

Originally Posted by harleytuner

Not exactly but you have the general idea. The stock rev limiter is a programmed function of the calibration. On drive by wire models the PC drives the crank signal above 5100 RPM's and clamps the signal and because the tach is wired off this circuit it stops at approx 5120 RPM's.

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Jan 24, 2010 | 12:12 PM

#15

riglide

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i find it is alittle strange when running with other people took pc out will try something else like an accurate tach signal.

Jan 24, 2010 | 01:05 PM

#16

harleytuner

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From: Fredericksburg, Va.

Quote:

Got it thanks. Basically PC has to trick the ECU to think it's not getting above 5100 RPM's. I was in the mind set that the ECU got the signal from the tach for some reason. but I hear what you are saying, makes sence to me.

Jan 24, 2010 | 07:37 PM

#17

papifun

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From: Quebec,Canada

Quote:

Originally Posted by fuelmoto

Jamie -I have the Stage1 download from HD with the PCV - should i have the revlimit in PC software with a check or not ?

Jan 24, 2010 | 08:28 PM

#18

harleytuner

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From: Fredericksburg, Va.

Quote:

Jamie -I have the Stage1 download from HD with the PCV - should i have the revlimit in PC software with a check or not ?

If you want your bike to rev to 6250 RPM check the box, if not leave it unchecked. It's not really a setting you have to have checked or not, it's a preference. I personally don't like the fact that the tach stops at 5100 or so RPM's and the bike keeps revving up. If you are "performance" riding you want to shift right before your bike hits the limiter, but when you can't see the tach it can be difficult. Just seems like a half assed way to get by the factory settings. I personally like my SERT, I raised my rev limiter to 6500 and my tach goes there.