Swap Carbs from Slides to CV

[Anonymous]

Has anyone swapped the older slide carbs for the CV types found on the 1980 and newer models?

Thanks for help.

Louie

[SqDancerLynn1]

Best bet for the older slide carbs is to find a set of 29mm smooth bore carbs $$$$$. If you want the new type carbs the easiest way would be to put a later model cyl head on your bike

[Anonymous]

You don't state which model GS you own. Lynn is probably referring to the GS850, which in its first year, 1979, came out with old-style slide carbs. In 1980 and thereafter the 850 had CV carbs.

The head is totally different in the 79 model GS850 from that on subsequent models with CV carbs. I stock lots of GS850 parts, but I don't have any more cylinder heads available.

Nick

[Anonymous]

1979 GS750 LN. Hope this helps with more info. Thanks in advance.

[SqDancerLynn1]

1980 the 750 started using the BS carbs , but also changed to from 2 valve to 4 valve so the heads will not interchange. SO you would have to make custom carb intake adapters and probably use pod filters. As a performance mod I don't thing you would gain much, because of the miss matching of the ports that would result.

[humhead]

SO you would have to make custom carb intake adapters and probably use pod filters. As a performance mod I don't thing you would gain much, because of the miss matching of the ports that would result.

The mismatch is bad enough that it might cause a power loss. 29mm smoothbores are an easy swap. The only issue would be the choke cable.
Finding a set is another matter. They've been out of production for awhile.
1980 850 heads are more common. If your wallet can stand it, adding an 850 piston kit will really make a difference. It would cost more but the results would be great.

[Anonymous]

Blew the 2 spark plugs out of the cylinder. Suspect last owners over torqued spark plugs. Cylinders are stripped. That now makes total of three. Motor is going to get rebuilt with the 844 cc WISECO piston kit.

What head should I put on why I am at it to help facilitate the carb swap to CV type carbs?

1979 GS750 LN

Louie

[first timer]

does anybody have pic of some 29mm smooth bore carbs, or know how to tell if you have them?

ryan

[humhead]

1980 or newer. Use the 750 cams. The 850 cams are more of a "midrange" power grind.