CARB question???

[Honzilla]

If I take out my big bulky air box from my 91' CB 750, and replace it with 4 individual air filters, do I need to have the carbs jetted???

[LukeM]

I can't speak for the 1991 models, but the carbs used on the 1979-1982 DOHC bikes were a constant vacuum design. They needed the restriction from the airbox to work properly.  The model number on those carbs was a VB42A/B/C depending on the bike model.

Making changes to either the intake or exhaust system usually necessitates a change in carburetion.  Opening up the exhaust (removing baffles) causes a lean condition. Same with running with no air filter, or opening up the inlet on the airbox (or running pods).

If you can get the model number off of your carb(s), perhaps someone can determine whether your setup will work.

Good luck, and keep us updated.
Luke M

[Honzilla]

Thanks Luke,

I am really ignorant about carbs, I thought the only difference was the manufacturer of the carbs and their respective sizes...

Is it difficult to remove the baffles from the exhaust???

The bike is REALLY nice and quite, which I like, however living in Hong Kong I need the bike to have some noise.  Car drivers here are totally ridiculous and unless you are sitting on their lap they don't know you're there.  I think I little more noise wouldn't hurt...

[Honzilla]

Thanks Luke,

I am really ignorant about carbs, I thought the only difference was the manufacturer of the carbs and their respective sizes...

Is it difficult to remove the baffles from the exhaust???

The bike is REALLY nice and quite, which I like, however living in Hong Kong I need the bike to have some noise.  Car drivers here are totally ridiculous and unless you are sitting on their lap they don't know you're there.  I think I little more noise wouldn't hurt...

[LukeM]

Removing baffles depends on the existing exhaust configuration.  On my son's CB550F, it was a matter of removing his muffler, reaching inside with some long nose pliers, and removing the inside.  His bike is essentially running straight pipes for exhaust.  It's loud...or let's say LOUD.  Not knowing what your exhaust is (aftermarket, or stock), I'd say take one pipe off and see if any of the insides can be removed without too much trouble, and leaving you the option of putting the baffle back in without destroying anything.

Hong Kong isn't the only place where "cagers" don't pay attention to bikers. In the first 10 minutes of me riding my new-to-me bike, 2 cars pulled out in front of me, without even looking my way.  I concur with your need to be heard and not just seen (or not seen, in this case).  I'd also recommend getting some good LOUD horns as well.

Luke M

[Honzilla]

LOL!  Ideally I want to put a train horn on her!

EVERYONE will know where I am...

[Honzilla]

Oh yeah, the pipes are stock as far as I can tell.