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-   -   Factory Rev Limiter? (https://www.hdforums.com/forum/exhaust-system-topics/583994-factory-rev-limiter.html)

dnlcrrgnHD 11-19-2010 07:40 PM

Factory Rev Limiter?
 
I have a 1999 FXR2 that is all stock except an andrews ev-51 cam i just installed along with an "180" jet in my stock keihin carb. This cam says that the rpm range is from 2500 to 6500 rpm's. But the bike still peters out just after 5000rpm like before the cam and jet swap. Is this a factory rev limiter im hitting or is the carb not big enough for this application? Help please.

1SG 11-20-2010 07:17 AM

when you hit the limiter you will know it, a different sound and the motor seems like it has a fouled spark plug. If you have a tac will it rev past 5000 at stand still, has it always done this or just started, have you checked for intake leaks, made all adjustements to carb, including cable adjustment, idle stops wide open stops, do you have a programble ignition crane, DTT, ect. and probably alot more more questions I can't think of.

JohnnyC 11-20-2010 09:13 AM

Factory ignition module limits revs to about 5,200 rpm, but you may notice the motor hitting it's peak at about 4,800 and then holding there. It may give a feel like it's shutting down.

I just installed a Crane HI4E ignition module and it has many adjustments and variables having to do with ignition timing, advance, spark and adjustable limits.

Now my bike shows red line on the tach at 5,000 rpms. With an older bike I really don't want to let it hit hi revs and destroy the stock engine. In your case just because the cam has a limit of 6,500 rpms doesn't mean the rest of the motor can handle spinning that fast without issues.

Also jetting up a carb and not allowing for better flow will leave you with a "too rich" condition. Typically carb re-jetting is done with the addition of better performance air filters and more flow in the exhausts by altering them in one way or another.

You will find a lot better performance, to start, with an ignition module upgrade.

dnlcrrgnHD 11-20-2010 12:35 PM

Well thanks for the input. It was helpful. I was really just wanting more power, this bike will barely get out of its own way.. lol.. However it only has about 13k original miles, so i figured that the engine would be able to handle about 6000rpms or so. The next step will probably be ignition or something to that nature. thanks again.

Mike T 11-20-2010 12:44 PM

Put a high flow A/C on and it will make a big difference.


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