Author Topic: 1977 cb750f2 (915cc)  (Read 240623 times)

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Offline bwaller

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Re: 1977 cb750f2 (915cc)
« Reply #900 on: November 10, 2013, 04:58:07 PM »
How many miles on the engine, could be the rings haven't completely sealed.

Like RR says that likely isn't a smoke issue.

Offline Retro Rocket

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Re: 1977 cb750f2 (915cc)
« Reply #901 on: November 10, 2013, 05:36:34 PM »
My thinking was that the RS34's have an accell pump and just blipping the throttle without load would lead to a bit of unburnt fuel or a rich condition momentarily, hence the puff of smoke....... ;)
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If You can't fix it with a hammer, You've got an electrical problem.

Offline tweakin

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Re: 1977 cb750f2 (915cc)
« Reply #902 on: November 10, 2013, 07:35:13 PM »
What headlight is that? Looks way better. Sounds awesome!
I never liked the chrome headlight, was just too lazy to change it.  Got this one from speedmoto.

Offline tweakin

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Re: 1977 cb750f2 (915cc)
« Reply #903 on: November 10, 2013, 07:36:12 PM »
My thinking was that the RS34's have an accell pump and just blipping the throttle without load would lead to a bit of unburnt fuel or a rich condition momentarily, hence the puff of smoke....... ;)
That is what I was also thinking RR, just wanted to put it out there for the sohc braintrust.  Only really happens after hard throttle chops.

Offline Retro Rocket

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Re: 1977 cb750f2 (915cc)
« Reply #904 on: November 10, 2013, 08:52:36 PM »
Whats the quality of the headlight and shell like ...?
750 K2 1000cc
750 F1 970cc
750 Bitsa 900cc
If You can't fix it with a hammer, You've got an electrical problem.

Offline bwaller

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Re: 1977 cb750f2 (915cc)
« Reply #905 on: November 11, 2013, 05:06:27 AM »
Without bashing the D2000 ignition, (most guys love them) I'm interested to read about you guys trying the Pamco. I bought two D2K's and it must have been at the height of their poor reliability period. One I junked, the other is still on my 750. I was going to reinstall the single pick-up Presolite I used for 35 years but instead may try this Pamco unit.

I have read some of the nonsence pro & con on the "P" unit the last couple years or so. It's good to read that "real world" riders having had good results.

Offline tweakin

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Re: 1977 cb750f2 (915cc)
« Reply #906 on: November 11, 2013, 06:57:26 AM »
Whats the quality of the headlight and shell like ...?
The quality is great for the shell, little disappointed in the actual light quality.  I am used to glass sealed beams but this one is plastic but puts out fantastic light.

Offline tweakin

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Re: 1977 cb750f2 (915cc)
« Reply #907 on: November 11, 2013, 07:05:25 AM »
Without bashing the D2000 ignition, (most guys love them) I'm interested to read about you guys trying the Pamco. I bought two D2K's and it must have been at the height of their poor reliability period. One I junked, the other is still on my 750. I was going to reinstall the single pick-up Presolite I used for 35 years but instead may try this Pamco unit.

I have read some of the nonsence pro & con on the "P" unit the last couple years or so. It's good to read that "real world" riders having had good results.

I too loved the dyna 2000 and never wanted to change.   After two separate pick up failures and the many $$ to replace / fix I decided to try something new.  Bike ran great with the Dyna as long as it was always moving and temperatures were in the 70 degree range.  It was as if the Dyna would heat up on hot days (90 degree) and the pick ups would fail.  BrandEn and Funjimmy both have had good success with the Pamco and the price was great. 

I hope to get out on the bike today for a test in riding conditions.  One thing is for sure, my bike fires up immediately  and idles smoother than it ever did before.

Offline Retro Rocket

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Re: 1977 cb750f2 (915cc)
« Reply #908 on: November 11, 2013, 11:32:49 AM »
Whats the quality of the headlight and shell like ...?
The quality is great for the shell, little disappointed in the actual light quality.  I am used to glass sealed beams but this one is plastic but puts out fantastic light.


Thanks mate... ;)
750 K2 1000cc
750 F1 970cc
750 Bitsa 900cc
If You can't fix it with a hammer, You've got an electrical problem.

Offline tweakin

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Re: 1977 cb750f2 (915cc)
« Reply #909 on: November 12, 2013, 06:05:15 AM »
Got out for a ride yesterday with BrandEn and the bike ran excellent with the Pamco, more than pleased with the results.  Comparing the two ignitions; easier starts, smoother idle, and the bike pulls just as hard as before.  The bike actually felt stronger, but it I believe it's all in my head.

I think the little puffs of smoke is the accelerator pump dumping extra fuel when hard on the throttle, no smoke when down shifting off throttle.

Offline iron_worker

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Re: 1977 cb750f2 (915cc)
« Reply #910 on: November 12, 2013, 06:59:26 AM »
Damn, that sounds good!  8) 8) 8)

I wouldn't be too worried about that little puff of smoke. I'd say it's probably fuel as well. Keep an eye on your oil consumption but I doubt it's anything to worry about.

IW

Offline SOHC4 Cafe Racer Fan

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Re: 1977 cb750f2 (915cc)
« Reply #911 on: November 12, 2013, 10:26:57 PM »
Does anyone with the Pamco know if it comes with the features of the Dyna 2000 -- rev limiter and RPM output for a electronic tach??
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Offline tweakin

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Re: 1977 cb750f2 (915cc)
« Reply #912 on: November 13, 2013, 06:04:33 AM »
Does anyone with the Pamco know if it comes with the features of the Dyna 2000 -- rev limiter and RPM output for a electronic tach??
No, it does not, just a basic ignition.

Offline NagChampa

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Re: 1977 cb750f2 (915cc)
« Reply #913 on: November 22, 2013, 10:46:41 PM »
Just finished reading this thread from the beginning over the last few days. Very very impressed with the attention to detail and top notch work. You are willing to tear that thing down to the last bolt at any moment, some may call that crazy and maybe it is but thanks for showing us how to do it the right way.

Offline Roland

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Re: 1977 cb750f2 (915cc)
« Reply #914 on: December 29, 2013, 12:31:17 PM »
Tweakin, what petcock did you use on this bike?  I am building a motor now and putting Mikuni RS 34's on my 77F but cannot figure out if I should put a different petcock on for better fuel flow.

Thanks!

Offline tweakin

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Re: 1977 cb750f2 (915cc)
« Reply #915 on: December 29, 2013, 01:59:55 PM »
I am just running a NOS petcock and Pingel fuel filter and a bit larger fuel line.
Tweakin, what petcock did you use on this bike?  I am building a motor now and putting Mikuni RS 34's on my 77F but cannot figure out if I should put a different petcock on for better fuel flow.

Thanks!

Offline tweakin

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Re: 1977 cb750f2 (915cc) Trying a new pipe
« Reply #916 on: January 14, 2014, 06:57:43 PM »
With the "Turd" (71 cb750 build) in full swing, I decide to try a new pipe arrangement on the 915.  The motoGP stainless pipe is awesome but still hit my remote filter housing since I am running an oil cooler plate, it fits fine on a stock set up.  Plan is for the motoGP pipe to go on the turd so I decided to do something different with the Kerker to get the look I want.

Had the Kerker header ceramic coated and added a Cone Engineering 2.5 inch stainless can on it, just the look I am going for.  Not sure how the performance differences will stack up but I am more than happy.  Just wish I had easier access to a dyno so I could have tested all the different pipe set ups.

Also picked up some new all black Joker Machine clutch and points covers, I like the simplified look of no fins.






Offline Roland

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Re: 1977 cb750f2 (915cc) Trying a new pipe
« Reply #917 on: January 14, 2014, 07:05:58 PM »
With the "Turd" (71 cb750 build) in full swing, I decide to try a new pipe arrangement on the 915.  The motoGP stainless pipe is awesome but still hit my remote filter housing since I am running an oil cooler plate, it fits fine on a stock set up.  Plan is for the motoGP pipe to go on the turd so I decided to do something different with the Kerker to get the look I want.

Had the Kerker header ceramic coated and added a Cone Engineering 2.5 inch stainless can on it, just the look I am going for.  Not sure how the performance differences will stack up but I am more than happy.  Just wish I had easier access to a dyno so I could have tested all the different pipe set ups.

Also picked up some new all black Joker Machine clutch and points covers, I like the simplified look of no fins.







I'm really liking the look of that cone on there, especially with the black headers.

Offline MRieck

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Re: 1977 cb750f2 (915cc)
« Reply #918 on: January 14, 2014, 07:12:59 PM »
Got out for a ride yesterday with BrandEn and the bike ran excellent with the Pamco, more than pleased with the results.  Comparing the two ignitions; easier starts, smoother idle, and the bike pulls just as hard as before.  The bike actually felt stronger, but it I believe it's all in my head.

I think the little puffs of smoke is the accelerator pump dumping extra fuel when hard on the throttle, no smoke when down shifting off throttle.
They will do that.
Owner of the "Million Dollar CB"

Offline tweakin

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Re: 1977 cb750f2 (915cc) Trying a new pipe
« Reply #919 on: January 14, 2014, 07:21:35 PM »
Thanks Mike.  I couldn't have built this engine with you you. 
Got out for a ride yesterday with BrandEn and the bike ran excellent with the Pamco, more than pleased with the results.  Comparing the two ignitions; easier starts, smoother idle, and the bike pulls just as hard as before.  The bike actually felt stronger, but it I believe it's all in my head.

I think the little puffs of smoke is the accelerator pump dumping extra fuel when hard on the throttle, no smoke when down shifting off throttle.
They will do that.

Offline cheftuskey121

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Re: 1977 cb750f2 (915cc) Trying a new pipe
« Reply #920 on: January 14, 2014, 07:24:05 PM »
looks good Tige...what are you playing at though...I have a cycle x 4-2-1 with matte black headers and SS cone. I had mine first, just not ON the bike. how does it sound?

Offline tweakin

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Re: 1977 cb750f2 (915cc) Trying a new pipe
« Reply #921 on: January 14, 2014, 07:27:36 PM »
 No documentation wit pics, so it never happened... ;D  I guess brilliant minds think alike.
looks good Tige...what are you playing at though...I have a cycle x 4-2-1 with matte black headers and SS cone. I had mine first, just not ON the bike. how does it sound?

Offline brandEn

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Re: 1977 cb750f2 (915cc) Trying a new pipe
« Reply #922 on: January 14, 2014, 08:21:01 PM »
That looks pretty sweet Tige. I bet its pretty loud. Can't wait to hear it. We should have some dry weather soon so you can give it a spin around the block.

Offline Retro Rocket

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Re: 1977 cb750f2 (915cc) Trying a new pipe
« Reply #923 on: January 14, 2014, 08:24:29 PM »
The cone looks good Tige, is it a 12 inch..?
750 K2 1000cc
750 F1 970cc
750 Bitsa 900cc
If You can't fix it with a hammer, You've got an electrical problem.

Offline tweakin

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Re: 1977 cb750f2 (915cc) Trying a new pipe
« Reply #924 on: January 14, 2014, 08:59:06 PM »
The cone looks good Tige, is it a 12 inch..?
thanks fellas.  I don't think it looks as good as the Motogp pipe but I can't have a pipe that hits my oil filter.  Yes Retro, it's the 12 inch. 
« Last Edit: January 15, 2014, 04:38:33 AM by tweakin »