Topic: 78 cb550K carb question

[weirdal]

I am hoping someone here can help. I pulled the carbs off my 78 cb550k and they are in bad shape, so I bought a set on ebay from the same year bike. Mine are stamped 46CAPH and the ebay ones are stamped 46CAPJ. What is the difference and will the new ones work on my bike? I am also having a hard time finding a set of rubbers from the airbox to the carbs as two of mine are ripped. Is there an aftermarket set available or a set of filters I can use instead of the stock airbox/filter setup that will not mess with my tuning at all?
Thanks
Dan

[lucky]

I am hoping someone here can help. I pulled the carbs off my 78 cb550k and they are in bad shape, so I bought a set on ebay from the same year bike. Mine are stamped 46CAPH and the ebay ones are stamped 46CAPJ. What is the difference and will the new ones work on my bike? I am also having a hard time finding a set of rubbers from the airbox to the carbs as two of mine are ripped. Is there an aftermarket set available or a set of filters I can use instead of the stock airbox/filter setup that will not mess with my tuning at all?
Thanks
Dan

Your carbs were not rebuildable???  Sure would like to see that.

[Lostboy Steve]

yeah... I'll take those un-rebuildable carbs off your hands.

[Scott S]

 I though the '78 carbs were PD series?
 There's a guy...a member here?..... who sells the replacement air box boots. For the life of me, I can't remember his name. Maybe someone will speak up?

EDIT: Here ya go:
http://www.classicmotorcyclesolution.com/

[TwoTired]

Mine are stamped 46CAPH and the ebay ones are stamped 46CAPJ. What is the difference and will the new ones work on my bike?

Of main concern is that they are both PD46C.   The rest of the letters mostly relate to a build date code (month/week), rather than some internal differences.  (That's an educated guess from an engineer who has seen this sort of thing elsewhere.  It has to do with failure tracking and quality control issues within the company, and what division/department gets the money hit on service callback charges.)

Cheers,

[weirdal]

Lucky,
I didnt say the carbs were not rebuildable, just in real bad shape. The posts the main jets are screwed into are rotted and badly pitted and I was afraid of twisting them off when trying to the main jets out.  I bought the other set because they were a good price and in great shape compared to mine. I will at some point rebuild mine as a spare set.

Scott,
The fellow that was making air box boots stopped production of his last year due to the compound he was using does not hold up to ethanol fuels.

TwoTired,
Thanks for the input on the stamp coding on the carbs. You were correct in your educated guess. That was confirmed by the fellow at sirius consolidated who was kind enough to point me at this page with lots of info on carbs.
h**p://www.motorcycleproject.com/motorcycle/text/specs.html

I picked up a set of aftermarket cone style filters for 15 bucks a piece from sirius consolidated. I got the bike fired up on sunday and it sounds pretty decent so far, I do think that I am going to have to enrich the mixture a bit. I havent been able to do a road testing on how it runs yet, still have to rebuild the forks and tinker with a couple other gremlins. But I am itchin like mad to take a spin on my first street bike 8-)

[Scott S]

Scott,
The fellow that was making air box boots stopped production of his last year due to the compound he was using does not hold up to ethanol fuels.

 Check again....he stopped making the boots that fit on the manifold side. The air box side doesn't really come in contact with fuel. I just got some boots from him a couple of months ago.

[weirdal]

I had a look at his site again and I guess I had misread his announcement earlier. Gotta love working night shift and a general lack of sleep lol
The air box connectors are available, I will shoot him off an email.
Thanks