Author Topic: 1977 cb750f2 (915cc)  (Read 240543 times)

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Offline tweakin

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Re: 1977 cb750f2 (915cc)DYNO RUN
« Reply #750 on: May 12, 2012, 07:22:05 PM »
Sounds gorgeous.... ;) Not bad numbers either mate, i've recently been told that you need someone who really knows the Mikuni's to set them up right but once right, they are the shizzle..... I wonder if Mike Rieck has some input on that..?

Thanks Retro...  I know there is more HP to be had but I don't want to go to stacks or a different exhaust.  Dave (DocterD) has a pretty good handle on the tuning of the carbs, my accelerator pump was sticking a bit, which is why the AF goes lean early, I will work that out this weekend.  I am more than happy with the numbers for now and the thing is super fun on the highway and around town.

Great job.  Your bike helped me with mine in so many ways.  Just Awesome...



Thanks cheapride, I appreciate the comments.  I know I am not the best at documenting the build process but I am happy you found my build useful.

Nice!

We F'rs need to stick together.  ;)

Offline VTEC

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Re: 1977 cb750f2 (915cc)DYNO RUN
« Reply #751 on: May 12, 2012, 07:36:40 PM »
I really wanted to stop by twinline today to check out your guys builds but didn't worked out. Maybe next time. The builds you guys have are awesome!!

Offline tweakin

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Re: 1977 cb750f2 (915cc)DYNO RUN
« Reply #752 on: May 14, 2012, 05:36:00 AM »
Too bad you couldn't make it by the shop.  Next time...
I really wanted to stop by twinline today to check out your guys builds but didn't worked out. Maybe next time. The builds you guys have are awesome!!

Offline immortal

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Re: 1977 cb750f2 (915cc)DYNO RUN
« Reply #753 on: May 15, 2012, 10:36:01 AM »
Very Nice tweakin!...I have a question for you. What spark plug do you use when you put in a big bore kit like you have. Perhaps a silly question but I'm curious if you need to use a different plug for a larger bore. I have an 811 bore but use standard plugs.
Sometimes...the hard thing and the right thing are the same thing!

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Offline tweakin

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Re: 1977 cb750f2 (915cc)DYNO RUN
« Reply #754 on: May 15, 2012, 07:14:33 PM »
Immortal-  I run Denso iridium plugs, one step cooler than stock.  So not really anything differnet plug wise than stock.  Hope that helps.  I am traveling for work so if you want the exact plug send me a pm or I can get it for you when I get back into town.
Very Nice tweakin!...I have a question for you. What spark plug do you use when you put in a big bore kit like you have. Perhaps a silly question but I'm curious if you need to use a different plug for a larger bore. I have an 811 bore but use standard plugs.

Offline Godffery

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Offline Old Scrambler

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Re: 1977 cb750f2 (915cc)DYNO RUN
« Reply #756 on: May 16, 2012, 06:35:53 PM »
Very nice build.........inside and out!  I think the 915 kits are going to be the new standard for the builders. I just picked up a set of RS34s for my long-term F2 project. 
Dennis in Wisconsin
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Offline tweakin

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Re: 1977 cb750f2 (915cc)DYNO RUN
« Reply #757 on: May 17, 2012, 04:51:11 AM »
Thanks for sharing Godffery.
Well, look'e here:
http://www.facebook.com/photo.php?fbid=411429032222325&set=a.235805653117998.65771.235679506463946&type=1&theater&notif_t=photo_reply

Thanks for the good word.  I love the 915 kit and other bits I added to the engine.  By the time you get your F2 all sorted out we should have a pretty good base line set up for the RS34's between all of us using them on the forum.
Very nice build.........inside and out!  I think the 915 kits are going to be the new standard for the builders. I just picked up a set of RS34s for my long-term F2 project. 

Offline Sam Green Racing

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Re: 1977 cb750f2 (915cc)DYNO RUN
« Reply #758 on: May 17, 2012, 08:32:30 AM »
 8) 8) 8) 8) 8) 8) 8) 8) 8) as fcuk Tige, you should be real proud of yourself. ;)

Sam. ;)
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Offline tweakin

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Re: 1977 cb750f2 (915cc)DYNO RUN
« Reply #759 on: May 17, 2012, 06:04:43 PM »
Thanks Sam!  You are talking about my black aluminum rims??? :P

I just picked up a Kerker with 2.5 comp baffle, hope to gain a few more ponies with a little less restriction.
8) 8) 8) 8) 8) 8) 8) 8) 8) as fcuk Tige, you should be real proud of yourself. ;)

Sam. ;)

Offline Sam Green Racing

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Re: 1977 cb750f2 (915cc)DYNO RUN
« Reply #760 on: May 18, 2012, 03:42:00 AM »
On some bikes they look good Tige, on others a mess, not forgetting, I have a bike with black wheels. ;D ;D ;D

http://forums.sohc4.net/index.php?topic=31154.475

Sam. ;)
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Offline tweakin

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Re: 1977 cb750f2 (915cc)DYNO RUN
« Reply #761 on: May 18, 2012, 05:19:56 AM »
I appreciate the good word Sam!  That bike of yours is so sweet...

On some bikes they look good Tige, on others a mess, not forgetting, I have a bike with black wheels. ;D ;D ;D

http://forums.sohc4.net/index.php?topic=31154.475

Sam. ;)

Offline MRieck

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Re: 1977 cb750f2 (915cc)DYNO RUN
« Reply #762 on: May 18, 2012, 07:02:49 AM »
Thanks Sam!  You are talking about my black aluminum rims??? :P

I just picked up a Kerker with 2.5 comp baffle, hope to gain a few more ponies with a little less restriction.
8) 8) 8) 8) 8) 8) 8) 8) 8) as fcuk Tige, you should be real proud of yourself. ;)

Sam. ;)
I imagine you will Tige.
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Offline tweakin

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Re: 1977 cb750f2 (915cc)Kerker
« Reply #763 on: May 19, 2012, 12:44:03 PM »
After my time on the dyno I decided to try out a new pipe that had a little less restriction than the Yamiya.  Although I like the look of the Yamiya (Yosh replica) better the Kerker is starting to grow on me.  I really wanted a pipe that would maximize the performance of the 915 kit.  Only time on the dyno will tell, but I love the sound of the Kerker with 2.5 competition baffle.



2.5 Competition baffle


Running video
Honda cb750f Kerker header

Offline voxonda

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Re: 1977 cb750f2 (915cc)Kerker
« Reply #764 on: May 19, 2012, 01:04:48 PM »
Sounds good to me! Yep, only the Dyno will tell which is better. Personally think the Yamiya is a very nice looking pipe but wonder if it's a real "power-pipe".

Just another quick question, were did you get that lovely seat?

Thanks, Rob
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Offline Retro Rocket

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Re: 1977 cb750f2 (915cc)Kerker
« Reply #765 on: May 19, 2012, 01:52:14 PM »
Tweakin, i was surfing one of the Japanese sites, {not too sure which one} anyway, you can get 2 different baffles for the Yamiya pipe. Also, you could get a baffle off Chris from Motogpwerks, they are very free flowing... :o ;D ;)
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Offline Godffery

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Re: 1977 cb750f2 (915cc)Kerker
« Reply #766 on: May 19, 2012, 02:03:13 PM »
Hey Man,
Why dose Your Vid say "BC" 750...?

Offline tweakin

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Re: 1977 cb750f2 (915cc)Kerker
« Reply #767 on: May 19, 2012, 02:26:40 PM »
Sounds good to me! Yep, only the Dyno will tell which is better. Personally think the Yamiya is a very nice looking pipe but wonder if it's a real "power-pipe".

Just another quick question, were did you get that lovely seat?

Thanks, Rob

Thanks Rob.  I had the seat custom built from a local shop in Seattle, Macs.  They did an excellent job and even added a gel pad for extra cush.

Yes, I agree the Yamiya is a nice looking pipe.  After the seat of the pants dyno (test ride) the Kerker is hands down a better performing pipe.  The bike performs much better at all rpm range's and feels like it just wants to go and go.

As you guys know a properly tuned pipe (length, diameter, baffle, ect.) makes all the difference on a performance build or any build.  Even if the dyno results are not any better I am sticking with the Kerker, just based on ride, but I will bet the performance gains are there. ;)

Offline tweakin

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Re: 1977 cb750f2 (915cc)Kerker
« Reply #768 on: May 19, 2012, 02:30:20 PM »
Tweakin, i was surfing one of the Japanese sites, {not too sure which one} anyway, you can get 2 different baffles for the Yamiya pipe. Also, you could get a baffle off Chris from Motogpwerks, they are very free flowing... :o ;D ;)

RR-  I had the largest baffle Yamiya offers and the smaller one, bike was tuned with the larger.  The larger baffle from Yamiya was bigger and better quality (IMO) than the Motogpwerks pipe I originally had.  By seat of the pant dyno the bike just doesn't compare.  I have put too much time and $$ into the engine build to let the pipe hold me back because of looks.

At first I hated the Kerker on my build but know that I have some saddle time and have seen the pipe on the bike from different angles, I love it.

Offline tweakin

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Re: 1977 cb750f2 (915cc)Kerker
« Reply #769 on: May 19, 2012, 02:32:19 PM »
Hey Man,
Why dose Your Vid say "BC" 750...?

I am color blind and dyslectic, ha ha  :o.  Thanks for the heads up, fixed.

Offline brandEn

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Re: 1977 cb750f2 (915cc)Kerker
« Reply #770 on: May 19, 2012, 02:42:21 PM »
Weren't you supposed to get rid of that pathetic pile of twigs in your garage? Haha!

I really like the look of the Kerker myself. The Yamiya is purty but man that Kerker is REAL purty IMO.

Offline FunJimmy

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Re: 1977 cb750f2 (915cc)Kerker
« Reply #771 on: May 19, 2012, 07:33:46 PM »
At first I hated the Kerker on my build but now that I have some saddle time and have seen the pipe on the bike from different angles, I love it.

The Kerker has a period correct look to it.
I like it too, and I'm not just sayin cause I have one.
Can't wait to see the dyno comparison.

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Offline Stev-o

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Re: 1977 cb750f2 (915cc)Kerker
« Reply #772 on: May 19, 2012, 09:26:43 PM »
Glad to hear good things about the Kerker, I have one stashed away for my K1 build.
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Offline Jerry Rxman Griffin aka MuthaF'er

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Re: 1977 cb750f2 (915cc)Kerker
« Reply #773 on: May 19, 2012, 10:52:03 PM »
Sounds nice. Just installed my new baffle the other day but I'm waiting on the copper seals or the pipe would be installed in the morning. It's pipes, ignition and carbs time! Then oil, brake fluid and GAS!! Started to pick up some 100 proof octane AV gas for the first firing but thought it might burn too hot before I make sure the carbs are set up correctly. I got a call from my dealer that my new rubber tube for the bottom of the oil breather/collector has arrived so I'm looking forward to seeing if this experiment will fit. I'll let you guys know provided you're still running your collectors. This is the one that is the drain and has the flare on it to fit on the collector bottom.

When's your next dyno run? 

Just noticed your mount for the Kerker. I'll get you a picture when I get mine installed. You'll want to change your's!  ;D
« Last Edit: May 19, 2012, 10:54:59 PM by Jerry Rxman Griffin »
As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)

Offline tweakin

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Re: 1977 cb750f2 (915cc)Kerker
« Reply #774 on: May 20, 2012, 06:36:38 AM »
You are getting close Jerry...   I do not run the collector anymore but am still interested in any upgrades or different ways to do things for future builds.

What baffle are you running?  2.5?
I am also curious to how you mount your Kerker, I actually don't mind the strap off the shocks but am open to options.  If I had the stock foot peg mounts it would be easy to mount there, but with the rear sets not as many options.  Shoot me over a pic once you get it mounted.

I hope to be back on the dyno soon, possibly this coming weekend.

Sounds nice. Just installed my new baffle the other day but I'm waiting on the copper seals or the pipe would be installed in the morning. It's pipes, ignition and carbs time! Then oil, brake fluid and GAS!! Started to pick up some 100 proof octane AV gas for the first firing but thought it might burn too hot before I make sure the carbs are set up correctly. I got a call from my dealer that my new rubber tube for the bottom of the oil breather/collector has arrived so I'm looking forward to seeing if this experiment will fit. I'll let you guys know provided you're still running your collectors. This is the one that is the drain and has the flare on it to fit on the collector bottom.

When's your next dyno run? 

Just noticed your mount for the Kerker. I'll get you a picture when I get mine installed. You'll want to change your's!  ;D