Author Topic: How much HP out of 736cc?  (Read 4681 times)

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Offline KB02

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How much HP out of 736cc?
« on: May 12, 2010, 04:19:03 AM »
It's not that I don't want one of Mike's fabulous blocks, but in thinking about my next project (heh! First one isn't even done yet) I was wondering just how much Horse Power can be squeezed out of the stock displacement for a SOHC4 750. I realize that it would all be in the valve train - Stage III porting, bigger valves, the right cam - but I'm just wondering what you guys think?

I just think it would be fun to pull up next to someone with an 836 (or 850) and to smoke them and just say, "Yeah, it's not bored out at all."
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Offline Sam Green Racing

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Re: How much HP out of 736cc?
« Reply #1 on: May 12, 2010, 05:50:06 AM »
Perhaps Mark (KOS) at M3 would be best to answer that one, but the highest output of the Daytona bikes in 1970 was 96bhp but they didn't last very long. :D
The thing to remember, the torque suffers when you start making big power and a good 836 (mine made 62ftlb) would still smoke you from the lights. ;)

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Offline Ecosse

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Re: How much HP out of 736cc?
« Reply #2 on: May 12, 2010, 12:18:50 PM »
musings from a neophyte?

since you wanna make power the hard way i'll assume you're not on a tight budget. first, use every trick in the book to harden/strengthen all the internals such as cryo, beefier parts, better materials.

then add nitrous oxide. you were just talking straight line, right?

also, get creative lightening the hell outta the bike. anyone can just rip bits off and call it a day. but that's not so stealth is it? i'd like to see a 'glass or aluminum replica of the stock tank. an aluminum or 'glass seat pan, a wee hi-tech battery, cycle x alternator, lose the starter, alum. rims and handle bars, etc...

just my 2 cents. adjusted for inflation.
   
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Offline kos

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Re: How much HP out of 736cc?
« Reply #3 on: May 12, 2010, 01:03:21 PM »

QUOTE:
Perhaps Mark (KOS) at M3 would be best to answer that one, but the highest output of the Daytona bikes in 1970 was 96bhp but they didn't last very long.


Nothing went wrong with top end of these high output engines...only bottom end primary chain failures.


We went 17 races in a row and won every one of them prior to any failure and that was just cam chain. Used one of those Yoshimura gear wheels  on tensioner arm, NO GOOD! Invented slipper system and never had a problem

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Offline kos

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Re: How much HP out of 736cc?
« Reply #4 on: May 12, 2010, 01:09:04 PM »
Back in the day I built a standard bore 736cc engine for a customer in the Honda shop I worked for. Used Pop's Yoshimura high compression pistons at zero deck,  Daytona Yosh cam, cleaned up ports, HD valve springs, re-jetted stock carbs & open K0 pipe.... that thing rocked.  No, can't get those pistons anymore but a set sold on ebay a few months back. I missed out!

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Offline MCRider

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Re: How much HP out of 736cc?
« Reply #5 on: May 12, 2010, 01:19:28 PM »
It's not that I don't want one of Mike's fabulous blocks, but in thinking about my next project (heh! First one isn't even done yet) I was wondering just how much Horse Power can be squeezed out of the stock displacement for a SOHC4 750. I realize that it would all be in the valve train - Stage III porting, bigger valves, the right cam - but I'm just wondering what you guys think?

I just think it would be fun to pull up next to someone with an 836 (or 850) and to smoke them and just say, "Yeah, it's not bored out at all."
Purely a seat of the pants opinion, but a stocker with headwork would likely pull an 836 without head work. I've had both. An 836 with headwork? No way.
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Offline NitroHunter

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Re: How much HP out of 736cc?
« Reply #6 on: May 14, 2010, 03:37:17 PM »
Q: How much HP out of 736cc?
A: About 150 with a turbo...  ::)
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Offline MRieck

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Re: How much HP out of 736cc?
« Reply #7 on: May 14, 2010, 06:12:38 PM »
Q: How much HP out of 736cc?
A: About 150 with a turbo...  ::)
That's it??? ::) ::) :D ;)
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Offline 754

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Re: How much HP out of 736cc?
« Reply #8 on: May 14, 2010, 07:50:46 PM »
Heyy how come with all the new advanced stuff.....

 nobody has outperformed Nitrohunters..

 10.0 in the 1/4 mile.. with stock CB 750  pistons.. ???
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Offline MRieck

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Re: How much HP out of 736cc?
« Reply #9 on: May 14, 2010, 08:13:27 PM »
Heyy how come with all the new advanced stuff.....

 nobody has outperformed Nitrohunters..

 10.0 in the 1/4 mile.. with stock CB 750  pistons.. ???
Honestly Frank....nobody is interested I'd guess. You need a stimulus package and a busa. ;)
« Last Edit: May 15, 2010, 05:31:31 AM by MRieck »
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Offline NitroHunter

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Re: How much HP out of 736cc?
« Reply #10 on: May 15, 2010, 10:09:26 AM »
MR you are SO right, building an ancient era time bomb cost just as much as putting together a modern go-fast... In these days why would anyone even want to do it when you can have a much quicker, highly dependable machine that you can get parts for?
 
Hell, I just put it together that way because I had a large conglomeration of used stock stuff and wanted to keep bracket racing for the summer. I slapped it together in one weekend and never imangined it would stay in one piece. ::)

But hey Frank if you are volunteering to try it, I'm sure that we can come up with modern tuning ideas that would work... for a few runs at least. ;D  ;D  ;D
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