That is a good thought, I had thought about that myself and was more on the lines of the ids would effect the inatial jump on the chart till the rubber cushions become compressed after hitting the gas.
Also from what I have read is that the tbw bikes like mine do not open the butterfly all the way untill a certan rpm to help prevent detonation even if you have it wacked all the way open.

Oh yea I think it will be a blast where it is at, but was just expecting a little more. The tq and hp on the print out looks long and smooth
I have not even rode it yet, still at the HD shop where I had it tuned.

 

James,
It doesn't matter either way.
I'm STILL gonna bust your *** with my HQ 107!

 

I think you may be on to something here...an old school indy that really knows his stuff told me to take the IDS off my bike and it would pull a lot harder/stronger...I won't do it because I really like the comfort on my bike...

 

You'd likely feel a harder hit when banging the gears, but that wheel is not gonna rotate any slower because of the rubber cushions. I just don't see the physics that could explain a loss in power. Engine rotates at a certain speed, the wheel has to follow.

Don't forget, that rubber cushion is also easing the shock on your crank. That is a good thing!




.

 

Is that rite?? You forget that I am a little lighter than you and I am also younger so these two together should make up for a couple hp or so..

 

I agree with you, I will not take it off!

 

The build results show less than 1hp per cubic inch.This is not typical of a Hillside build.I would be digging for answers.I would start with the tune,exhaust,& then the heads.Did you call Scott??

 

I am not suggesting anyone removes their IDS. The IDS in no way slows the bike down out on the road. It just creates error on the dynojet dyno.

Remember dyno dynamics dynomometers (dynojet) DO NOT directly measure engine power. They measure how fast the engine accelerates the dynojet flywheel and calculate the power from that.

The problem is that the engine is not just accelerating the dynojet flywheel, it is accelerating the back wheel, IDS, belt, gearbox, primary, flywheels and rotating engine parts.

The dynojet dyno assumes all bikes have the same rotational inertia, which is a very rough assumption.

A bike with a smaller and lighter back wheel will appear to have more power on a dynojet dyno. Similarly a bike with heavier flywheels and a chain primary will appear to have less power than a bike with light flywheels and a belt primary. Even a worn tyre will make a difference.

Wanna know more:
http://www.factorypro.com/dyno/true1.html

Dynojet dynos are a cheap and nasty way of measuring power. They were never designed to be able to compare power outputs between bikes, there are just too many variables.

 

Yeah, I'd think the additional weight of the 180 rear tire and the wider heavier Rim would have more effect than the 5 or so rubber cushions in the IDS.

Also, many folks have IDS's on 07s. We should ask them how their Dyno runs were effected if any.

My vote is for the ECM/TBW being the major difference...

lp

 

It's no secret that the 6 speed sucks up power, or that a larger, heavier wheel will reduce power on a dyno.

Still, I think his numbers are low.