at the crank? and hp question.

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jmillheiser · #11 Post by **jmillheiser** » Sun Jul 09, 2006 2:52 pm

the R1 has come a long way then. One of my friends has an 05 R1 that puts out a hair over 160hp to the back wheel.

kabob983 · #12 Post by **kabob983** » Sun Jul 09, 2006 3:04 pm

Yeah, the newer ones pull over 180 hp at the crank, of course, all literbikes have come a "long way since then." Yamaha was a bit ahead of their time too, Suzuki didn't come out with the Gixxer 1000 till '01 or so, 2 years after the R1 came out. Kawasaki didn't make the 10R until even later than that I believe. And Honda dabbled with the 929, 954, and then finally the 1000RR in '04.

So really all of our current "superbikes" have come a long way in a very short time.

TechTMW · #13 Post by **TechTMW** » Sun Jul 09, 2006 7:51 pm

jmillheiser wrote:bhp is the amount of hp at the crank.

Yes.

VermilionX wrote:so if the bike has 150hp... i wonder how much bhp it has.

First off, Verm. EVERY BIKE IS DIFFERENT. Subtle differences in the manufacturing process, oil typ and weight, break-in procedure, riding style, and maintenance schedule all have an affect on how much power your engine is producing.

Your bike probably doesn't have 150BHP. You need to dyno it to know for sure.

Finally, as a comparison. A chain drive bike will transfer appx 98% of the power from the Transmission output shaft to the rear wheel. (A belt will lay down appx 93% and shaft 85%) The transmission also causes parasitic losses, but that's different for each bike, since the metallurgy of the shafts, gears, lubrication, number of gears, etc all have a say in how much power gets thru the tranny.

PS, The K6 750 has a claimed BHP of 148 (It's called CLAIMED because the manufacturer can't guarantee that's what your bike has. There's a remote possibility it's got more, but more likely your bike is actually a few BHP's weaker)

Anyway, MOTORCYCLIST magazine Dynoed a k6 750 and came up w/ 129.1 WHP (And keep in mind, that's at 13,250 RPM. You don't even hit 120hp until you are at about 11,000 rpm.) At 6000 - 8000 RPM you are only putting about 60hp to the ground. So. Unless you ride at at 10,000 RPM constantly, you're normally playing w/ less power than an SV650.

I know you don't care, and for you it's all about the numbers, But High-Side hit the nail on the head in this post. viewtopic.php?t=14289

earwig · #14 Post by **earwig** » Mon Jul 10, 2006 12:50 am

VermilionX wrote:i also heard that chains are more sturdy and better for aggressive riding compared to a belt.

This is not true. Race bikes use chains because they can be adjusted easier/on the fly to accommodate different track conditions.

kabob983 · #15 Post by **kabob983** » Mon Jul 10, 2006 12:57 am

Yeah, the track day I worked at yesterday was hosted by Buell and they had a ton of demo bikes, all of which were belt driven. I believe their XB-RR's were also belt driven (didn't help much I suppose).

earwig · #16 Post by **earwig** » Mon Jul 10, 2006 1:04 am

kabob983 wrote:Yeah, the track day I worked at yesterday was hosted by Buell and they had a ton of demo bikes, all of which were belt driven. I believe their XB-RR's were also belt driven (didn't help much I suppose).

XBRR are chain driven. The pre-production bikes at daytona sucked... they claim to have all of the problems worked out... we'll see I guess.

Dichotomous · #17 Post by **Dichotomous** » Mon Jul 10, 2006 1:42 am

[quote="TechTMW Unless you ride at at 10,000 RPM constantly, you're normally playing w/ less power than an SV650.
viewtopic.php?t=14289[/quote]

which is exactly why I have no care to upgrade. 10k rpm is just a little nutz to run around all the time with

Sev · #18 Post by **Sev** » Mon Jul 10, 2006 2:17 am

earwig wrote:
VermilionX wrote:
Sevulturus wrote:i also heard that chains are more sturdy and better for aggressive riding compared to a belt.
This is not true. Race bikes use chains because they can be adjusted easier/on the fly to accommodate different track conditions.

I didn't say that.

Learn to quote.

earwig · #19 Post by **earwig** » Mon Jul 10, 2006 4:35 am

Sevulturus wrote:I didn't say that. Learn to quote.

Bite me, I know how to quote... It's called a mistake and I am sorry

I notice your quote is screwed up as well... Learn how to quote!

DieMonkeys · #20 Post by **DieMonkeys** » Mon Jul 10, 2006 4:45 am

I don't know why but I always though bhp was British Horsepower, you know how those crazy Britons always have to be different for us Uh-murh-ih-cans, what with that weird metric system and whatnot.