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Discussion Starter #1
I was just looking and the RR, out of the 05 lineup, has the lowest CR at 12:1. Everyone else is anywhere from 12.3:1 to 12.9:1.

Is it just me or wouldn't bumping the CR up to 12.9:1 boost the HP by at least 4-5? Given the HP wars between these bikes, you can do 12:9.1 and still run pump gas and have a reliable bike.

I imagine if I bought the HRC cams and shaved and ported the head with a full Arata TI system and PC I could get at least 120 at the rear wheel. Maybe a wee bit more. That's race legal too, isn't it?
 

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Uping compression can cause a whole slew of problems...overheating, pinging(from lack of octane), decreaced engine life, etc...if you want those extra 4-5 HP, get a good slip-on and a PC3 and be happy! Honda made it the compression ratio it has for a reason.
 

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If you want HP, just by a damned 1000...geez :roll:

Reliability is key and the best way to get rid of it is to start tearing the motor apart.
 

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Discussion Starter #5
I just asked a question, sheesh. I'm comparing the other 3 makes, who have higher compression engines, and I don't see it negatively effecting their reliability.
 

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We're just answering your question.

Each engine is unique and engineered differently. The CR is a by-product of many factors that go into engine design. None of these motors are engineered to acheive a specific CR. They set the CR in order to acheive a certain level of performance and reliability.

So to compare CR's between bikes is sorta like comparing the OEM spec tires they come with. Its not necessarily an apples to oranges comparison, but its not really a meaningful one either. Just an interesting fact to know about the individual motor.

I hope that helps out a little more.
 

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Discussion Starter #7
Eck said:
We're just answering your question.

Each engine is unique and engineered differently. The CR is a by-product of many factors that go into engine design. None of these motors are engineered to acheive a specific CR. They set the CR in order to acheive a certain level of performance and reliability.

So to compare CR's between bikes is sorta like comparing the OEM spec tires they come with. Its not necessarily an apples to oranges comparison, but its not really a meaningful one either. Just an interesting fact to know about the individual motor.

I hope that helps out a little more.
This answer is a lot better than telling me to go buy a 1000RR :) I have a 1200 so I'm not drooling for HP.

I'm also pretty mechanically inclined so I know what boosting CR does for an engine. I guess my point was that given the fiercely competitive 600 class, you'd think Honda would join their rivals and BEAT them in the HP game with a more competitive CR. The Kawi isn't making all that extra HP from 36ccs, it's the 12.9:1 CR that's giving it the extra HP. I can't see the 36ccs giving it that much of a boost.
 

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At the pro racing level, that 36cc's may make the difference. But maybe there's some dynamic in the 600RR motor that prevents the Honda engineers to increase the CR. Honda is known for reliability so I'm guessing that they lose quite a bit of reliability when they increase the CR. But my speculation isn't going to get us closer to the answer so I'll just leave it at that :)

Also, the bikes are engineered with street riding in mind, not racing. So having a good midrange with a nice even torque curve is probably more beneficial than a few top end HP's. But again, total speculation on my part.
 

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comparing compression ratios between differently designed engines is pointless . the last test i saw ( rrw 600 shootout ) the rr only made less hp than one of the bikes tested , though it had the lowest comp ratio . also 36cc comes to a 6% increase in displacement , and in theory , should net an increase of about 6% more hp capability .
 

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Discussion Starter #10
r6beater said:
comparing compression ratios between differently designed engines is pointless . the last test i saw ( rrw 600 shootout ) the rr only made less hp than one of the bikes tested , though it had the lowest comp ratio . also 36cc comes to a 6% increase in displacement , and in theory , should net an increase of about 6% more hp capability .
It makes 3 less than the R6 and 7 less than the 636. That would make it 3rd (equal to the Trumpet, a few more than the GSXR).

Both the R6 and 636 have higher CR's than the RR. Bumping the CR will have no negative effect on this engine and boost the HP to make it a bit more competitive. The 36ccs on the 636 don't really matter THAT much. It's the CR (It's 12.9:1 vs the Honda's 12:1 - that's a pretty big difference in a cut throat class.
 

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It makes 3 less than the R6 and 7 less than the 636.
the gsxr has a higher cr than the cbr rr and the r6 , yet makes less hp . the zx6rr has the same cr as the 636 , yet makes the same hp as the cbr rr . 7 hp more for the 636 falls in with the extra 6% displacement . the 36ccs really are the difference .
 

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Discussion Starter #12
r6beater said:
It makes 3 less than the R6 and 7 less than the 636.
the gsxr has a higher cr than the cbr rr and the r6 , yet makes less hp . the zx6rr has the same cr as the 636 , yet makes the same hp as the cbr rr . 7 hp more for the 636 falls in with the extra 6% displacement . the 36ccs really are the difference .
7hp from 36ccs seems a bit high, though. That's 1 hp for every 5.2ccs.
 

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Also, you have to take those dyno #'s with a grain of salt. They didn't state when & where they dyno'd each bike. When I baselined my '05 bone stock, it dyno'd 106.2 peak where an R6 on the same dyno (different day) only ran 104.3.

Dyno #'s vary widley between even the same model of bike. In closing, we still haven't and will never definitely answer your question. And I don't think anyone cares to try anymore :razz:
 

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Discussion Starter #14
Eck said:
Also, you have to take those dyno #'s with a grain of salt. They didn't state when & where they dyno'd each bike. When I baselined my '05 bone stock, it dyno'd 106.2 peak where an R6 on the same dyno (different day) only ran 104.3.

Dyno #'s vary widley between even the same model of bike. In closing, we still haven't and will never definitely answer your question. And I don't think anyone cares to try anymore :razz:
Yeah, yeah :razz:

I do know that different bikes of the same model, depending on how they were broken in and what dyno they were on can vary wildly on their HP #'s.

I just don't hink 36ccs can possibly make THAT much of a difference. Granted, on the track the RR is just a few thousands of a second off and that can just be rider comfort.
 

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Eck said:
If you want HP, just by a damned 1000...geez :roll: .
yeah Brian, get yourself a 1200, take it completely apart and powdercoat the hell out of it, and add a 1216 kit, and port/polish it, and do all sorts of other go-fast mods and get it over with....oh wait, you've already done that...sorry. :bitchslap:

haha, sorry, I couldnt resist.

get that f'ing RR out to the track already!
buttonwillow, april 18
willow big track april 26
again may 25
again june 22
and so on...
 
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