06-03-2009, 03:34 PM | #71 | |
WERA White Plate
Join Date: Nov 2008
Posts: 1,059
|
Quote:
Hp is torque over a period of time, gearing will change torque, but not hp. So by the time you change the gearing of a 10,000 rpm twin to match a 15,000 I4, you lose 33% of your torque. As to why a twin won't make the same hp is valve area and rpm. The bigger valves of a twin take up more space across the chamber, and the valve area doesn't increase as fast as displacement does, so you end up with less valve comparably, and the mass of the valve is a key limit to rpm and cam profile and spring life. Smaller valves have less mass and can rev higher. Hp is all about torque over time, higher rpm if you can maintain torque makes more hp. F1 engines and now MotoGP engine show a similar development paths. More smaller cylinders that rev higher, with exotic methods to close the valves. |
|
06-03-2009, 03:41 PM | #72 | |
Chaotic Neutral
Join Date: Feb 2008
Location: Cherry Hill NJ
Moto: GV1200 Madura, Hawk gt
Posts: 13,992
|
Quote:
|
|
06-03-2009, 03:52 PM | #73 | |
Moto GP Star
Join Date: Mar 2008
Posts: 14,556
|
Quote:
|
|
06-03-2009, 03:54 PM | #74 |
WERA White Plate
Join Date: Nov 2008
Posts: 1,059
|
|
06-03-2009, 03:56 PM | #75 | ||
DefenderOfTheBuelliverse
Join Date: Feb 2008
Location: Parts Unknown
Moto: Buell XB12R
Posts: 18,585
|
Quote:
__________________
Quote:
|
||
06-03-2009, 03:59 PM | #76 |
Moto GP Star
Join Date: Mar 2008
Posts: 14,556
|
|
06-03-2009, 04:04 PM | #77 |
Aspiring Rapper
Join Date: Nov 2008
Location: Halifax, NS
Moto: '12 CB1000R
Posts: 3,569
|
Strange how one estimate is conservative and at the wheel. And the other is peak claimed at the crank....
My 2000 r6 supposedly made 120 at the crank. My buddies 07 puts 116 to the wheel with a full system and a custom dyno tune.. The 1125 with tuning and race system might put 130-135 to the wheel. Stock they see mid 120s at the wheel. |
06-03-2009, 04:10 PM | #78 | |
Nomadic Tribesman
Join Date: Nov 2008
Location: Brampton, Canada
Moto: '09 ER-6n
Posts: 11,150
|
Quote:
__________________
"Everything's better with pirates." - Lodge, "Dorkness Rising" http://www.morallyambiguous.net/ |
|
06-03-2009, 04:21 PM | #79 |
WERA White Plate
Join Date: Nov 2008
Posts: 1,059
|
|
06-03-2009, 04:21 PM | #80 |
Elitist
Join Date: Nov 2008
Location: SF Bay Area
Moto: Gix 750
Posts: 11,351
|
If it's a Ducati.......but not a Buell. Lol. When is the last time a Buell had the top-end of a Duc or even an Aprilia.
Last edited by Homeslice; 06-03-2009 at 04:25 PM.. |
Bookmarks |
Thread Tools | |
Display Modes | |
|
|