Topic: 1976 CB750A Discontinued and unavailable Carb. Isolators?

[KingCustomCycles.com]

I wanted to give some of you a heads up, and to ask if there is a source for CB750A Carbureter isolators?  They are discontinued from Honda and Dennis Kirk has none.  EBAy came up dry....Thanks!
(These are the rubber boots that mount the carbs to the engine)

[KingCustomCycles.com]

Follow up........I just scored a good used set on eBay for $30.00.  They were listed less than 3 hours.  This does not solve the long term and frankly disturbing spectre of these parts not being available.   

[Soos]

How are they different from 750k rubbers? (are the K andF's different as well?)

l8r

[medic09]

There was a place in Germany that was marketing them for all the SOHC bikes.  They post them on Ebay every so often.

[KingCustomCycles.com]

How are they different from 750k rubbers? (are the K andF's different as well?)

l8r

That is what I was hoping to find out.  I suspect a cross reference to a K model but don't know. 

[medic09]

How are they different from 750k rubbers? (are the K andF's different as well?)

l8r

That is what I was hoping to find out.  I suspect a cross reference to a K model but don't know. 

Did you check cross-reference # on a parts fiche, like Bike Bandit or HondaPartsDirect?

[KingCustomCycles.com]

Yes, they are unique according to my local Honda Dealer.

[Soos]

So are the carbs different? Or the head?
I would imagine that would be the two determining factors for these SOHC 750's and the carb isolators....

Any cb750A owners know whats up??


(not that I own a 750...yet.  but i'm curious!)

l8r

[rbmgf7]

the insulators are different then all of the CB750's. the internal diameters are quite small and a smaller set of carbs were used (can't remember the bores). there was a link somewhere i saw on here a couple years ago that had the specs but i can't find it anymore after the webpage moved. someone started a hondamatic website so you can go there to find more info on it.

[eldar]

I think the carbs were 26mm or 2 mm smaller than the K. I would check david silver I suppose.

[troppo]

If you can find an original honda parts number go here
http://www.motogrid.com/pages/parts/viewbybrand/7/default.aspx
It will give you a list of every honda that used the parts

[05c50]

I can add some info about this subject. The 750A uses PD carbs,similar to the cb550 carbs. The outside diameter where the boot slides on is about 33mm. I believe the K and F carbs are about 36mm. Thats only half the problem. The real problem is that the PD carb rack is not as wide as the 750A/K. In other words, the carbs are mounted closer center to center. The two outside boots on the 750A are shaped with a wierd angle to make them fit from the wide 750 spigot spacing to narrow 550 carb rack. I hope this makes sense.
I tried to find new ones,but never found any. They will only fit the 3 years of 750A.
Here's a link to the Hondamatic forum http://autos.groups.yahoo.com/group/hondamatic/
Hope this helps

.........Paul 

[Soos]

The carbs sound as if they are VERY similar to cb650 '79 mechanical carbs with those measurements...

Anyone have any carbs for a Auto 750 they can measure??

I have a post comparing the measurements of a set of '79 650 carbs and '73 cb750 carbs....

Just wonderin'...


l8r

[KingCustomCycles.com]

Oddly enough I am doing carb work on a 1980 CB650 and the 76 Hondamatic at the same time here.  I will compare the boots when I get them and do some measuring on the carbs and engines.

[Soos]

Awesome!




l8r

[troppo]

Those part numbers are not used on any other honda bikes