Topic: Carb swap-but one issue remains

[Mr. Mike]

Hello all,

Had a friend swap out my 1978K PD carbs for a set of 74 round tops. I like the cold starts and responsiveness of the new old carbs, but the original air box boots don’t clamp down on the carbs like they should (I know some of you are nodding your heads already because you know this).
So, who has done what to compensate for this gap between boot and carb?

Thanks

[BomberMann650]

Can you get the boots for the model you need?

[Mr. Mike]

Yes that’s the easy part, but I understand they won’t fit my original air box diameter-wise. Maybe I need an earlier air box, or someone’s good garage mod idea.

[seanbarney41]

Yep, just use the earlier air box and boots

[Mr. Mike]

Thank you sir!

[seanbarney41]

pm me if you need an earlier(k1-k6) airbox...been going through stuff lately and I have a bountiful plentitude of these

[77379]

I don’t mean to butt in, but are there any differences in the K1-K6 air boxes, each one of mine says HM CB750F on the air box. These are on my 750K1 and K4. I was wondering what the F stands for and if this is the correct air box for my 750K.

[Mr. Mike]

My 78 says HM CB750F-F
I’m no guru but when searching for an air box for years early 70 through mid late 70’s they say the same box fits several models, so I’d say yes, the boxes you are using are correct for your years. CMSNL shows the same p/number for K1/K6. As far as the F goes...i don’t know.