Topic: Carb swap cb500 vs cb550??

[dergs713]

Are carbs from a 75 honda cb550f the same as a  73cb500f..? My 73's look pretty bad, an i fell upon a set off of a 75 550 that are in good shape.  Are they universal? they look very much the same to me.
Matt

[Bankerdanny]

Based on the specs here: http://www.sohc4.net/?p=338

They are no the same. However, they may work anyway as they are the same basic carb type and use the same jet sizes.

What do you mean by 'look pretty bad'.

[zojirushi]

My CB500 came with CB550 carbs.  They work fine.

[TwoTired]

The carbs look the same externally, but have different internal parts and adjustment settings which are matched to the induction and exhaust system.

If it's all stock, there will be some drivability issues swapping carbs.  However, both carb sets can be internally modified to work wherever.  But, it's not predictable beforehand with non-stock induction and exhaust components.   Many believe "close enough" is just fine, though.

Swapping will work.  It's up to the mechanic to determine how well.

Cheers,

[Danno]

the later 550 carbs will have leaner characteristics but as two tired said you have to try them and see they are the same profile so they will go into the boots just fine

if the boots are too stiff then boil them in wintergreen oil the process is here on the forum

I have also had good luck dipping them quickly in evapo rust wiping off the excess and letting dry over night  don't dip them for more then 5 seconds at a time if they are still not soft enough after the first time then you can dip them again

[dergs713]

Thanks a lot guys, and thanks a bunch danno for the tricks, will be putting them to use!
Matt