If you are using the stock cam there is no reason to go beyond 5500 since you stop making power at approx 4200 rpm.
Unbalanced, it's funny you would say that. Not funny ha, ha, but it does surprise me just a bit.
This is my dyno sheet of an '08 SERK with V&H Dresser Dual, V&H Oval mufflers, SE AC upgrade and a PCM III installed. Not that my dyno sheet is anything to write home about, it isn't, but it does show my HP still climbing up to about 5,400 rpms. Granted my torque was gone long before that, but the seat of the pants dyno can tell a difference between the stock rev limiter and the bumped up to 6,200 rpm rev limiter.
Usually getting onto the freeway in second and third gear I would hit my 5,500 stop very quickly. The bike was still gaining pretty good at that point. Now with the rev stop lifted up to 6,200 rpms, I seldom hit it and the bike does not die out over 6,000 rpms. I know the dyno sheet contradicts my butt dyno, but I really prefer the higher limiter.
On my last rod project, I had a new 540" BBC with 660 hp. The builder builds hundreds of these motors and he recommended a shift point of 6,500 rpms with my peak hp dropping off at about 6,000 rpms. He said that during the shifting it will keep me more in tune with the available power. I think in the case of the 110" and its 6 speed, that theory would not hold up as the rpm drop per shift is less that the 4 speed automatic I was running in the car.
I know there is a lot of hupla going on right now on dyno sheets, one bike to another. My sheet is using the dyno for a very good purpose. The base line was with the same hardware, but with Power Commander's very first web map available. It ran great, but didn't get the mpg I thought I should and I was curious in what it put out. So the dyno chart shows my power when I drove up and the after is when I left the dyno. He gained my about 9 hp over what I had and as you can see, the torque made overall big improvements. Afterwards, I increased my mpg about 6 on the average; went from 33 up to about 39/40 range. The bike also seemed to have more throttle response.
I guess now that I've rambled on and on and on, sorry..... I have to say I'm very happy with the added rpms available with my setup. Whether it's all in my head or not, I do feel that I've gained upper end with the higher limit and it performs when needed even at those higher rpms.
Fourstar still raises a good point about the stroke and the rpms. Just think on my now sold 540" BBC, it had 4.38" stroke and 4.5" bore and again, he wanted me to shift at 6,500 rpms. Boy is that a lot of mass flying around inside that motor. I think the weight involved in the 110" motor is better suited for the 6,200 rpms than my V-8 was. I guess, within reason, I'd rather have an under square motor than an over square motor. 110" over square and the 540" under square. In the V-twin genre, over square seems to be the norm and V-8's all seem to be a bit less than square. Piston speed is the killer in a motor.
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Topic: Rev limiter 110" (Read 2758 times)