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Have i got the right carbs?

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FatFreddy:
Now that i've got the old girl firing on all four cylinders at the right time, it's time to sort out the carbs. (no groaning at the back please).

The engine in my bike was a replacement for a severly knackered F2 (conrod for cylinder 1 came away at 90mph and did a very good impersonation of a certain gut-busting scene from Aliens). It's a F1, and it didn't come with any carbs. So after some time perusing ebay, i got hold of a set.

However, i'm not entirely sure i've got hold of the right type, ie i think the ones i've got are somewhat too old for the engine and thereby i'm not going to get the best performance. Do you mind having a look at the pics below and helping me out. Should i replace them with something more recent/better?

 

Post edited by: FatFreddy, at: 2007/03/26 22:53

JonnyB:
Hi Freddy,

Those are of the same type as the F1 in fact all the CB750 used that type up untill the F2.

The way I see it, if it idles and runs up to 70/80mph without ant flat spots, chances are the're fine.

Check your plugs - See chapter 3 in the Haynes,

The main problem with eBay carbs I found is that you never know if the last own tweaked any thing.

Voxonda:
Hey there,

I agree, carbs are the same on the F1 and the K models, only the K7 and F2 have other carbs, although the same innerdia, these have accelerator pumps and pressed in primary jets. Be happy with the ones you've got, because they are easier to adjust.

Good luck.

FatFreddy:
Cheers chaps.
Just thought i has better make sure before i start sorting them out. The bikes running rich on 3 cylinders, doesn't rev out like it should, not as powerful as it should be, and sounds rough despite sorting out the timing. You can hear occasional 'popping' in the exhaust when she's warmed up and ticking over. I guess that'll be excess fuel not being burnt up in the cylinder.

Well then, i've got meself some carb balancers, so it's time a learnt how to use them. Any tips or things to look out for when sorting these carbs out?

Cheers

JonnyB:
I found Balancing with a set of vacuum guages a pain, and couldn't get it right, in the end I had to remove the carbs and manually setup the float heights. After that it all settled down.

Good louck and remember :S it's only a hobby :S

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