DYNO Numbers for Baggers???
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Not necessarily. I've seen very nice trq/hp curves with both older and newer bikes with similar engine upgrades. The only difference is the peak hp/trq. You'll see far more hp/trq from a 2003 103 then you will with a 2011 103 that has very similar engine upgrades. Both will have nice flat trq curves but the peak #s will be 5-10% lower on the newer bike.
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Not necessarily. I've seen very nice trq/hp curves with both older and newer bikes with similar engine upgrades. The only difference is the peak hp/trq. You'll see far more hp/trq from a 2003 103 then you will with a 2011 103 that has very similar engine upgrades. Both will have nice flat trq curves but the peak #s will be 5-10% lower on the newer bike.
Last edited by mtclassic; Dec 10, 2011 at 02:56 PM.
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When John Sachs bored, decked, & ported my 2007 motor (A wire also), he installed a Kury 52mm intake. We talked long about the new "fly by wire" controller, and, being an electrical engineer, I dug into it quite deeply. I found nothing on dampening the initial onset (perhaps this was added AFTER the 2007's started to "Scissor" their crankshafts?). John DID complain about the new helical gears in the 6 Speeds "eating up 10 Hp". He mentioned this so often, that I thought about retrofitting an older tranny, since I'd invested so much already, and hated to lose 10 ponies. Just thought for the table . . . Stoood ; )
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From: Roseville, CA
If indeed the TC88/95s were straight cut gears, giving better dyno readings, or in your case the same (same dyno and conditions?), then it's the transmission.
Since its been established the 6speed trannys are not an OD, the extra gear ratio in the given speed range make for quicker acceleration.
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The other big difference that could account for the lost power is the fact that we are no longer in direct control of the throttle once the bike has a Throttle-by-wire controlled by the ECU as in the newer bikes.
That older engine had no technician between your throttle hand and the power coming from the engine. The only thing between your throttle hand and the engine's response is a cable on that older bike. Sure that cable could get stretched or not be adjusted properly but you were in control.
Once we went to having a design tech riding with you at all times with software code used by the ECU to convert your throttle position to power, we essentially gave up some throttle control to the MoCo. They can embed code that modifies how the engine responds to the throttle position and the change in throttle position.
It's my opinion that the coding in the ECU that manages throttle response can be somewhat improved by tuning software adjustments however I still believe there remains inherent torque management coding that is buried in the ECU that at least partially contributes to the reduced performance of newer engines versus older engines of the same displacement.
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From: bklyn,ny
That will do it, it seems. So the TC88s were all straight cut?
I think we're on to something here.
If indeed the TC88/95s were straight cut gears, giving better dyno readings, or in your case the same (same dyno and conditions?), then it's the transmission.
Since its been established the 6speed trannys are not an OD, the extra gear ratio in the given speed range make for quicker acceleration.
I think we're on to something here.
If indeed the TC88/95s were straight cut gears, giving better dyno readings, or in your case the same (same dyno and conditions?), then it's the transmission.
Since its been established the 6speed trannys are not an OD, the extra gear ratio in the given speed range make for quicker acceleration.
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Joined: Apr 2007
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From: Roseville, CA
Yep that sounds about right but I really struggle to believe the addition of a 6th gear resulted in a 10% power lose for a similar configured engine with the same displacement.
The other big difference that could account for the lost power is the fact that we are no longer in direct control of the throttle once the bike has a Throttle-by-wire controlled by the ECU as in the newer bikes.
That older engine had no technician between your throttle hand and the power coming from the engine. The only thing between your throttle hand and the engine's response is a cable on that older bike. Sure that cable could get stretched or not be adjusted properly but you were in control.
Once we went to having a design tech riding with you at all times with software code used by the ECU to convert your throttle position to power, we essentially gave up some throttle control to the MoCo. They can embed code that modifies how the engine responds to the throttle position and the change in throttle position.
It's my opinion that the coding in the ECU that manages throttle response can be somewhat improved by tuning software adjustments however I still believe there remains inherent torque management coding that is buried in the ECU that at least partially contributes to the reduced performance of newer engines versus older engines of the same displacement.
The other big difference that could account for the lost power is the fact that we are no longer in direct control of the throttle once the bike has a Throttle-by-wire controlled by the ECU as in the newer bikes.
That older engine had no technician between your throttle hand and the power coming from the engine. The only thing between your throttle hand and the engine's response is a cable on that older bike. Sure that cable could get stretched or not be adjusted properly but you were in control.
Once we went to having a design tech riding with you at all times with software code used by the ECU to convert your throttle position to power, we essentially gave up some throttle control to the MoCo. They can embed code that modifies how the engine responds to the throttle position and the change in throttle position.
It's my opinion that the coding in the ECU that manages throttle response can be somewhat improved by tuning software adjustments however I still believe there remains inherent torque management coding that is buried in the ECU that at least partially contributes to the reduced performance of newer engines versus older engines of the same displacement.
Somewhere in my research about the OD debate, I came across a list of gear ratios. It would be an interesting comparison.