Topic: CB550 Carburetor bore out?????????

[L.A. Nomad........]

I've seen some small carburetors bored out out before, has anyone tried this on a 550 carburetors yet? The alternative would be to get larger carburetors from a CB750, but how difficult would that be to setup??

Eddie
 

[masonryman]

I am no expert, I think the carbs breath better than the engine, unless there are several upgrades on the top end and a much better exhaust

Mark

[Soos]

Another option is to use cb650 carbs.

Either the (1979)650 or the 750 carbs would be a larger bore and be a much easier transition than the time/money involved in boring your 550 carbs out IMO.

But it's your wallet/time here.... how much of either do you have?


It also depends on whether you want a accel pump as well, the 78/77 carbs on the 750 have them, 76 and earlier didn't.
The 650 (1979) carbs have an accelerator pump also.
Some thoughs to take into consideration when swapping carbs is any mods you have/intend on doing, as well as cost of the carb rebuild kits.

The '77/'78 750, and the '79 650 carbs all have accel. pump diaphragms, as well as air cut-off diapragms.
So add 15.00 per air cutoff diaphragm, and about 30.00 for the accel pump diaphragm.


So a rebuild of a '76 or earlier carbs is about 70.00...
A 77/78 cb750 & '79 650  carb set rebuild will cost you in the neighborhood of 170.00!!!
70+(approx cost of kits) and another 100(cost of 4 air cutoff diaphragms, and 1 accel pump diaphragm).


I had thought of this for my 650 carbs... and decided just getting a set of older (pre-'77)750 carbs was way easier.
I went for a set of '73 carbs(they were cheap through E-bay) for my '79 650 due to the re-build kits only costing less than 70.00 for all four carbs.

l8r