DYNO Numbers for Baggers???

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Oct 7, 2011 | 02:55 PM

#2851

harleytuner

Outstanding HDF Member

Joined: Mar 2009

Posts: 3,253

Likes: 222

From: Fredericksburg, Va.

Quote:

Originally Posted by Heatwave

The video evidence is that an Ultra in mostly stock form with about 75 hp and a 5sp transmission can achieve about 104-105mph (GPS) when the engine is fully wound out. Given the exponential factor of air resistance, an Ultra will absolutely need at least another 25 hp and probably more like 30hp to generate another 15+ mph top end speed.

But then again Don Quixote thought he cold defeat a windmill with his lance, so I guess anything is possible in the mind of those that wish hard enough

yeah it's video evidence that this basically stock bike can reach a speed of about 105 MPH on the street, Look back at the sheets I posted, you'll see a camparable HP bike reaching speeds of 116 MPH on a dyno in 4th gear. I've NEVER said in here or anywhere that a basically stock (or stage I) bike can reach 120 MPH. I've only argued that it doesn't have to be 120 HP to reach those speeds. Like I've said. My wifes LowRider (96" with 211 cams can and will reach speeds in excess of 120 MPH). You kep throwing out that they need over 100 HP but have offered absolutey no proof.

Last edited by harleytuner; Oct 7, 2011 at 03:07 PM.

Oct 7, 2011 | 07:43 PM

#2852

coolerman69

Road Warrior

Joined: Aug 2010

Posts: 1,788

Likes: 5

From: Tennessee

Quote:

Originally Posted by harleytuner

If you have all stock gearing etc, etc. In 4th gear at 6250 RPM's your theoretical speed would be 122.1 MPH. Red line in 5th gear would be 149.7 MPH assuming your bike could get to 6250 RPM's in top gear. Keep in mind that these numbers are NOT accounting for Cd, friction and all that other crap. In 5th gear your bike would hit 121 MPH at 5000 RPM's

Thanks HT! Hell i was close. Like I said in an earlier post......My speedo {(according to gps) is ssslllllooooooowwwwww. So if we are going by the math method, which is never wrong, when my bikes speedo reads 120 and my rev limiter kicks in, i'm actually doing 122! This cant be! I have stock heads and less than100hp!

Oct 7, 2011 | 07:49 PM

#2853

coolerman69

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Joined: Aug 2010

Posts: 1,788

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From: Tennessee

Quote:

Originally Posted by Heatwave

But where do the rpms stall in 5th gear? That will likely be the top speed of the bike.

The only way i gain speed in 5th on this bike is goin down a big hill. Now my 95 incher is a whole different story!

Oct 7, 2011 | 08:01 PM

#2854

coolerman69

Road Warrior

Joined: Aug 2010

Posts: 1,788

Likes: 5

From: Tennessee

Hey y'all. I got into a little duel last night with a Victory and that mother was fast! I was a little worried at one point. My speedo was pointed straight down! How fast is that?

Oct 7, 2011 | 08:02 PM

#2855

harleytuner

Outstanding HDF Member

Joined: Mar 2009

Posts: 3,253

Likes: 222

From: Fredericksburg, Va.

Quote:

Originally Posted by coolerman69

Like I said though, that speed is theoretical, it's not taking wind resistance, friction, etc into consideration.

Oct 7, 2011 | 09:12 PM

#2856

mtclassic

Outstanding HDF Member

Joined: Oct 2007

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I have seen 165mph on my speedometer but it was on a honda XX probably an actaul 150-155 and it was pretty relaxing tell my buddy passed me on his 'busa like I was going backwards, said his speedo was showing 185.

Oct 8, 2011 | 10:04 AM

#2857

Heatwave

Member

Joined: Jul 2009

Posts: 4,310

Likes: 1,079

Quote:

Originally Posted by harleytuner

So show me evidence of an HD bike that can hit a GPS measured 120hp and has less than 100hp? You're not gonna find one with the possible exception of a jacked up sporty or dyna that has 100hp and even that's a maybe. You're simply not gonna get an HD Touring bike (or even a softail with shield and bags) to 120+ mph without making the investment to build out 100hp.

The example shown of a 75hp Ultra winding out to 105mph is perfect evidence of that fact. Those next 15mph to get from 105 to 120mph will need alot more power to overcome the exponentially rising air resistance that will be needed to get to 120mph. And the only way that's gonna happen is if the engine generates a bare minimum of 100hp and probably more.

Last edited by Heatwave; Oct 8, 2011 at 10:08 AM.

Oct 8, 2011 | 10:16 AM

#2858

Heatwave

Member

Joined: Jul 2009

Posts: 4,310

Likes: 1,079

Quote:

Originally Posted by coolerman69

OK, you guys finally have me convinced....I just had to find out for myself what 115hp could really do with enough stretch of open highway.

I took the TP off to get the best possible Cd and I really tucked down behind my windshield. It took a long run but I just let it wind out. I guess I had enough HP and Torque to reach my rev limiter (6250) in 6th gear since I had alot of open smooth roadway. I finally hit my rev limiter in 6th gear and I was going 167mph!!! Man.... was I cooking

I'm now with you guys..... the math and physics had to be wrong all along!!!

Last edited by Heatwave; Oct 8, 2011 at 10:23 AM.