Topic: need!! 1976 CB750A carb holders/intake manifolds

[cully76cb750A]

Hey everybody !! I am in need of a set of carb holders/intake manifolds for my 1976 CB750A. I have dug all over the internet and called many places today with no luck. If anyone knows where I can get a set please direct me. Thanks. Dean C.

[05c50]

Dean, I currently make boots for the 77/78 750A and have plans to make ones to fit the 76. How soon did you need them? Here's a picture of my reproductions


Maybe I can help

...........Paul

[cully76cb750A]

I would need them asap, spring has finally sprung in Michigan and they are the only thing holding me up on my carb rebuild. Also the 76 has 24mm carbs on it not 28mm like so many people and articles say.

[05c50]

You have a pm.

..............Paul

[chickenman_26]

Hey everybody !! I am in need of a set of carb holders/intake manifolds for my 1976 CB750A. I have dug all over the internet and called many places today with no luck. If anyone knows where I can get a set please direct me. Thanks. Dean C.

Just to be clear, do you need the air box boots shown, or do you need the parts between the engine and carbs?

Stu

[05c50]

The boots shown are the the carb to head isolators, not the ones between the air box and carb. I'm pretty sure that's what he needs.

............Paul

[cully76cb750A]

Hey paul, Ya what I need is what we are talking about carb holders/intake manifolds which are on the engine side between the head and carbs, not the airbox boots. I do need to know what you mean by pm. thanks.

[754]

05c50.. are you saying you are making the manifold rubbers?
 Can you custom make a few sets for me?

 I need short ones about 1.25 inches long for my Weber manifolds.

 I can make the molds if need be, let me know..

[05c50]

Hey paul, Ya what I need is what we are talking about carb holders/intake manifolds which are on the engine side between the head and carbs, not the airbox boots. I do need to know what you mean by pm. thanks.

PM = personal message. If you click on my forum name (05c50, highlighted in blue, top left corner, above avatar) it will take you to my profile page. Scroll down to the bottom of page, you'll see "send a pm" Click on it. You can send a message just like an email. If you send your phone number and the best time to call, we can discuss the boots.

..............Paul

[05c50]

05c50.. are you saying you are making the manifold rubbers?
 Can you custom make a few sets for me?

 I need short ones about 1.25 inches long for my Weber manifolds.

 I can make the molds if need be, let me know..

Yes, I can make them. Do you have a sample. If not, what material would you use for the mold?

.............Paul

[chickenman_26]

The boots shown are the the carb to head isolators, not the ones between the air box and carb. I'm pretty sure that's what he needs.

............Paul

Sorry - I should have looked at my bike more closely.

[754]

I could make the mold out of steel or aluminum.
 Is it poured cold or hot?

 Is it completely fuel proof?

 Is it (as far as you know ) machineable after the fact.

 If I knew where to get it, I would try it. Or I can maybe help you .

[05c50]

Sorry it took so long to get back to you, but to answer your questions.... The material I'm using is a 2 part urethane that does not require heat to harden. The manufacturerer expects the material to last approx. 30 years. Some testing has been done to assure that it is fuel proof. I soaked samples in gasoline, alcohol, brake fluid, and Seafoam. The only effect was that the gasoline softened the surface slightly after soaking for 30 days. After air drying for a day, it returned to normal.
The cured boots have a shore hardness rating of 60, approx. the same as tires. It is machineable using high speed grinders and drills.
Hope this answers your questions. I'm sure we can make something work for you.

...........Paul

[754]

If you picture a 750 intake spigot, and another 1/4 in away, but the tween portion being the same ID as the port.. that is what I need.. plus enough room for a clamp on each end.

At least 3 sets..

[WNY750A]

I have a pre-production set of Paul's carb isolators and I can tell you he did a great job on them. They fit and seal and after 30 years my 750A's carbs are actually isolated from the engine vibration. I highly recommend them.

Bob

[05c50]

Thanks for the kind comments, Bob.   I was trying to figure out your screen name (wny750a) WhiNeY 750A?    Did you get out for a ride today? It was beautiful here wpa.  

...........Paul

[scottly]

05c50.. are you saying you are making the manifold rubbers?
 Can you custom make a few sets for me?

 I need short ones about 1.25 inches long for my Weber manifolds.

 I can make the molds if need be, let me know..

Frank, I used some fabric reinforced, silicon hose for my Webers. Got it from a local industrial supply place; I think they said it was used in gas pumps...

[754]

Last time I tried to mount a manifold, the best I came up with was fuel hose, but to get it on, I had to strip one soft layer and one braid layer... dont recall having that much trouble back in the day..
 Also I never liked the fact that between the 2 spigots the id of the hose is bigger than the ports..


 Anyway I have contacted 05c50, and he has given me a decent price on 4 sets, 16pcs, which takes care of my end for now.. well maybe 1 or 2 more sets.

 So if anyone else needs the short rubbers for Webers, speak up now..

 We were talking about 1.25 long  that is 1/4 in of reduced diameter in the middle (port size), plus 2 clamping areas.

 This will take care of my splayed MPD manifolds plus another style with similar int ends, but straight line carb mounting.

[scottly]

Sorry it took so long to get back to you, but to answer your questions.... The material I'm using is a 2 part urethane that does not require heat to harden. The manufacturerer expects the material to last approx. 30 years. Some testing has been done to assure that it is fuel proof. I soaked samples in gasoline, alcohol, brake fluid, and Seafoam. The only effect was that the gasoline softened the surface slightly after soaking for 30 days. After air drying for a day, it returned to normal.
The cured boots have a shore hardness rating of 60, approx. the same as tires. It is machineable using high speed grinders and drills.
Hope this answers your questions. I'm sure we can make something work for you.

...........Paul

Paul, where do you get this stuff? Sounds like it would be useful for making all kinds of parts!!!
Thanks,
Scott

[scottly]

OMG!!! You guys have developed the cure for Involuntary Poditutude!!! There is hope for all those that need the carb-to-airbox rubbers that seem to be made of unobtainium!!  

[scottly]

 Also I never liked the fact that between the 2 spigots the id of the hose is bigger than the ports..
 

Me neither, but I always considered it a necessary evil, and lived with it... I'll PM you.

[Clyde]

Paul,
if you are making some 76 CB750A head to carb manifolds, I also need a set for my 76 Automatic.
Thanks
Clyde
Sydney Australia

[gaskog]

Paul:
Thanks for the great  intake manifolds....fits great.
Was it so youcould make the airfilterbox boots to?

Geir ARne
Norway

[Curtimatic]

Paul, I realize this is a very old thread but I was hoping you were still making the 77-78 750a boots?

[ceebass68]

Thanks Curtimatic for reviving this thread. I would be interested in a set for a 76 750a...!