DYNO Numbers for Baggers???
Can I put the same gearing and drive ratios in the Streetglide?
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I am thinking an R6/R1has a huge CD advantage over a street glide so not sure if you could even out the odds by strappng a barn door to the front of the yammy. Now if you add enough weight to the R6 with its low torq motor you might burn the clutch out before attaining any type of speed at all.
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all very entertaining in a scientific geeky sorta way i guess but it's kinda like comparing peak numbers on a dyno chart, doesn't tell the whole story and makes no difference in the real world.
yes on paper weight plays little to no part in top speed but in the real motorcycle world heavier means bigger which means more surface area which means lower top speed.
sorry but a built 140 hp streetglide won't come within 20 mph of a 140 hp R6. that's real world....
yes on paper weight plays little to no part in top speed but in the real motorcycle world heavier means bigger which means more surface area which means lower top speed.
sorry but a built 140 hp streetglide won't come within 20 mph of a 140 hp R6. that's real world....
And if you could strap the SG's fairing, forks and fender on the R6 to get it close to the Cd of the SG (without adding any additional weight), it would still beat the SG (with the same 140hp) because of the extra 450lbs. That much flab would result in more rolling resistance for that 140hp to push, which would make a measureable difference in the top end speed.
Last edited by Heatwave; Oct 6, 2011 at 02:58 PM.
This arguement is getting old. I'm saying that weight will not make a significant differnce in overall top speed. You're saying it does. I guess the argument would be what we consider significant. I will concur that weight will add to the friction of the bearing etc. But I don't concur that it would make that great a differnce. now if the weight you are adding is mass, i.e. riding 2 up, that wold make a differnce just with the extra drag. But if I filled up my tour pack with 200 LBS of lead, the only changes that would be made are on the friction, (top speed would be effected very very minimaly), but the distance to acheive top speed would be effected greatly.
When I argue that HP doen't effect top speed, I am assuming that the bikes have the power to reach the redline, that's why I used a redline of 4000 RPM's as an example. I will say that a 140 HP bike would have the same top speed (theoretically, if all componets were equal CD, friction, gearing etc.) as a 200 HP bike. Here's even a comparison to prove my point. In this attatchment I compared 4 differn't bikes, all differn't build, the speed line is practically identical to all of them. At 6200 RPM's they was at most a .26 MPH differnce. From the 74 HP bike to the 121 HP bike.
When I argue that HP doen't effect top speed, I am assuming that the bikes have the power to reach the redline, that's why I used a redline of 4000 RPM's as an example. I will say that a 140 HP bike would have the same top speed (theoretically, if all componets were equal CD, friction, gearing etc.) as a 200 HP bike. Here's even a comparison to prove my point. In this attatchment I compared 4 differn't bikes, all differn't build, the speed line is practically identical to all of them. At 6200 RPM's they was at most a .26 MPH differnce. From the 74 HP bike to the 121 HP bike.
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This arguement is getting old. I'm saying that weight will not make a significant differnce in overall top speed. You're saying it does. I guess the argument would be what we consider significant. I will concur that weight will add to the friction of the bearing etc. But I don't concur that it would make that great a differnce. now if the weight you are adding is mass, i.e. riding 2 up, that wold make a differnce just with the extra drag. But if I filled up my tour pack with 200 LBS of lead, the only changes that would be made are on the friction, (top speed would be effected very very minimaly), but the distance to acheive top speed would be effected greatly.
When I argue that HP doen't effect top speed, I am assuming that the bikes have the power to reach the redline, that's why I used a redline of 4000 RPM's as an example. I will say that a 140 HP bike would have the same top speed (theoretically, if all componets were equal CD, friction, gearing etc.) as a 200 HP bike. Here's even a comparison to prove my point. In this attatchment I compared 4 differn't bikes, all differn't build, the speed line is practically identical to all of them. At 6200 RPM's they was at most a .26 MPH differnce. From the 74 HP bike to the 121 HP bike.
When I argue that HP doen't effect top speed, I am assuming that the bikes have the power to reach the redline, that's why I used a redline of 4000 RPM's as an example. I will say that a 140 HP bike would have the same top speed (theoretically, if all componets were equal CD, friction, gearing etc.) as a 200 HP bike. Here's even a comparison to prove my point. In this attatchment I compared 4 differn't bikes, all differn't build, the speed line is practically identical to all of them. At 6200 RPM's they was at most a .26 MPH differnce. From the 74 HP bike to the 121 HP bike.
OTOH comparing the top end of 2 bikes with similar aerodynamics and the same HP/gearing where one weighs 500-600lbs more than the other will DEFINITELY make a MEASURABLE difference in top end speed. And the difference with be several mph when maxing out in the 120mph range.
A 200hp bike will reach a higher top end speed than a 140hp bike with the same gearing UNLESS both bikes never reach their top speed until they touch the same rev limiter. Generally that is unlikely as the 140hp bike will hit the "wall" of air and rolling resistance long before before it hits the rev limiter in its highest gear.
But IF both bikes are capable of winding out in their top gear all the way to the rev limiter (same setting) and have the same gearing...then yes...they will both be at the same top end speed. I just think that's a highly unlikely situation (and a waste of 60hp in the bike that could have just as easily done it with 140hp).
The bike with 200hp should either have higher gearing or another gear to reach its full top end potential which will definitely be higher than the 140hp bike. In your example you are artifically holding back the more powerful bike from achieving its real top end speed by forcing it to go no faster than the maximum rpm of the 140lb bike. In that case, the top end speed of both bikes are identical since they are both at the same rpms with the same gearing.
The point being that more hp absolutely enables any bike to achieve higher top end speed than a lower hp motor when both bikes can use the full range of their power and have the same gearing. Once again a simple matter of math. But I get your point...if you were to constrain the 140hp bike to the gearing and rpm range of a 50hp dirt bike, then give them both the same rev limiter, they would both reach the exact same top end speed. Which doesn't mean the 140hp bike wasn't capable of a higher top end.
Last edited by Heatwave; Oct 6, 2011 at 03:26 PM.
We actually agree to a large extent. In the real world adding an additional 130lbs (passenger for example) is very unlikely to be enough added weight to measurably change the top end of a bike. And I've said that multiple times.
OTOH comparing the top end of 2 bikes with similar aerodynamics and the same HP/gearing where one weighs 500-600lbs more than the other will DEFINITELY make a MEASURABLE difference in top end speed. And the difference with be several mph when maxing out in the 120mph range.
A 200hp bike will reach a higher top end speed than a 140hp bike with the same gearing UNLESS both bikes never reach their top speed until they touch the same rev limiter. Generally that is unlikely as the 140hp bike will hit the "wall" of air and rolling resistance long before before it hits the rev limiter in its highest gear.
But IF both bikes are capable of winding out in their top gear all the way to the rev limiter (same setting) and have the same gearing...then yes...they will both be at the same top end speed. I just think that's a highly unlikely situation (and a waste of 60hp in the bike that could have just as easily done it with 140hp).
The bike with 200hp should either have higher gearing or another gear to reach its full top end potential which will definitely be higher than the 140hp bike. In your example you are artifically holding back the more powerful bike from achieving its real top end speed by forcing it to go no faster than the maximum rpm of the 140lb bike. In that case, the top end speed of both bikes are identical since they are both at the same rpms with the same gearing.
The point being that more hp absolutely enables any bike to achieve higher top end speed than a lower hp motor when both bikes can use the full range of their power and have the same gearing. Once again a simple matter of math. But I get your point...if you were to constrain the 140hp bike to the gearing and rpm range of a 50hp dirt bike, then give them both the same rev limiter, they would both reach the exact same top end speed. Which doesn't mean the 140hp bike wasn't capable of a higher top end.
OTOH comparing the top end of 2 bikes with similar aerodynamics and the same HP/gearing where one weighs 500-600lbs more than the other will DEFINITELY make a MEASURABLE difference in top end speed. And the difference with be several mph when maxing out in the 120mph range.
A 200hp bike will reach a higher top end speed than a 140hp bike with the same gearing UNLESS both bikes never reach their top speed until they touch the same rev limiter. Generally that is unlikely as the 140hp bike will hit the "wall" of air and rolling resistance long before before it hits the rev limiter in its highest gear.
But IF both bikes are capable of winding out in their top gear all the way to the rev limiter (same setting) and have the same gearing...then yes...they will both be at the same top end speed. I just think that's a highly unlikely situation (and a waste of 60hp in the bike that could have just as easily done it with 140hp).
The bike with 200hp should either have higher gearing or another gear to reach its full top end potential which will definitely be higher than the 140hp bike. In your example you are artifically holding back the more powerful bike from achieving its real top end speed by forcing it to go no faster than the maximum rpm of the 140lb bike. In that case, the top end speed of both bikes are identical since they are both at the same rpms with the same gearing.
The point being that more hp absolutely enables any bike to achieve higher top end speed than a lower hp motor when both bikes can use the full range of their power and have the same gearing. Once again a simple matter of math. But I get your point...if you were to constrain the 140hp bike to the gearing and rpm range of a 50hp dirt bike, then give them both the same rev limiter, they would both reach the exact same top end speed. Which doesn't mean the 140hp bike wasn't capable of a higher top end.
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From: SW Minnesota
I just had our '06 Ultra TC88 dyno'ed this past Tuesday. Engine is stock, except for the addition of Andrew's 21G's. I'm running a SE K&N air cleaner with a Boyesen X-Wing, a set of cheap modified Road King stock mufflers, and a just installed Cobra PowrPro for fuel tuning. After five pulls, the PowrPro pretty much dialed itself in, and we got 74.77 Hp and 78.67 ft/lbs on the fourth pull. I was especially pleased to see the Andrews 21's pulling strong and steady already from 2200 rpm. The dyno tech told me to definitely get some better exhaust to pull better torque numbers, but I'm happy with what I have for the conservative riding I usually do.
The top and bottom line on the a/f chart are the first and second pulls. The auto tuning PowrPro then ran the a/f in the next three pulls in between the first two.
Here's a video I shot while testing out the PowrPro. Due to the mount it's upside down.
http://www.youtube.com/watch?v=kl3hCXqKCaY
The top and bottom line on the a/f chart are the first and second pulls. The auto tuning PowrPro then ran the a/f in the next three pulls in between the first two.
Here's a video I shot while testing out the PowrPro. Due to the mount it's upside down.
http://www.youtube.com/watch?v=kl3hCXqKCaY
Last edited by MNPGRider; Oct 6, 2011 at 08:36 PM.
Cruiser
Joined: Oct 2008
Posts: 132
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From: Northern Nevada
2006 FLHTPI
95"
100-100
PP, decked to match cc Heads, 10:25:1 se pistons, woods tw6, DD fatcat, power commander, K&N air cleaner
91 octane Avg 37 MPG at 70mph +
2002 FLHRCI
stock 88"
87-95
se 203, thunderheader, K&N air cleaner, powercommander
91 octane avg 32mpg
95"
100-100
PP, decked to match cc Heads, 10:25:1 se pistons, woods tw6, DD fatcat, power commander, K&N air cleaner
91 octane Avg 37 MPG at 70mph +
2002 FLHRCI
stock 88"
87-95
se 203, thunderheader, K&N air cleaner, powercommander
91 octane avg 32mpg