Topic: Cb 500 carb upgrades

[winnipeg550guy]

Hello all, sort of new here used to have a login but it's been along time, anyways my question is about carbs.

 I finally found a suitable 500cc motor (from 73' cb500) to drop into my Rigid Bobber CB550 frame, due to insurance costs I'm downsizing, $700.00 difference in insurance rates just by downsizing to 500cc or lower motors I Know It's Nuts!!

 Tore apart Cb500 carbs &  thier pretty gummed up been sitting for long time, since I've got all kinds of CB550 parts lying around
  I wondered if the 550 carbs would fit? They appear to be exactly the same,  Need re-jetting? jet sizes?, I'm running pod filters which ran good on the 550 but may not on the 500
 
 

[TwoTired]

The non-PD carb bodies for the CB500 and 550 are from the same castings.  The jetting and various internal bits and pieces are different among models.  The carb bodies are stamped with a number to indicate the internal setup.  627A, 627B are found on the CB500s.  CB550 can have 022A, 087A, 069A and some others I haven't encountered as european specific variants.

The set up for each carb body is tailored for the air filter, exhaust type, and displacement of the as-delivered model from Honda.

There is a chart in the FAQ that outlines known differences.

Even if you have carbs with a proper setup stamp laying around, what are the odds they have already had internal parts swapped or modified by someone along with other bike configuration changes?

All the internal parts will swap.  But, I'm not sure the solid tipped air screws found on the 069As should be swapped.

What is it about carb cleaning that deters you?

Cheers,

[SteveD CB500F]

What was your previous username?

We may be able to resurrect it.

[winnipeg550guy]

Can't even remember my previous username it may have been the same not sure though.
As far as cleaning goes I already been working on the 550 carbs over the previous months when time allows, polishing and such. Just thought I could save myself a few weeks/months of work. But maybe I'll finish up the 550carbs & sell them off then get to work on the 500's
            Thanks for the info I'll have a look for those charts in FAQ's 

[Soos]

Why not drop that 550 motor into the 500 frame?(will this work??)

It's dancing around fine print.... but who would be able to tell the difference?
Unless you have a cop that is a honda nut, no one would be the wiser.
Heck... a 650 motor might fit as well, I know a 650 motor in a 550 frame is possible.




l8r

[TwoTired]

The 550 cylinder block has 544cc cast into it, facing forwards.
The 500 Cylinder block has 498cc cast into it.

I have a 605cc kit for the 500 cylinder block. 

There is also the issue the engine serial number beginning with the engine displacement. 

Cheers,

[winnipeg550guy]

Want to keep the 550 frame because I've Stretched & hardtailed the rear end, so I wanted to drop the 500 motor in it, eventually pick up a bigbore kit for it