Mikuni Across the GS range

[Samiam]

Hey guys. So, while rebuilding my carbs(again!), I had the cheapo-chinese replacement air screws disintegrate in their impossible to reach tunnels. I have tried everything short of black magic to get them out, so at this point I just want to get a replacement rack. Bike is a 1980 GS550 with Mikuni BS32SS carbs. Will the carbs from a corresponding 750/850/1000 fit, or are they different diameters? Thanks for your help!

[Steve]

Up through 850 is the same diameter, but the length of the arms between #2 and #3 is longer on the 750 and 850.

You will have to restrict your search to 550 and 650 carbs.

The "choke" mechanism is a bit different on the '82 and newer bikes, but the old one will fit right on.

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[Sci85]

Steve, which arm would that be? Can you replace the arms with those from the 550/650 rack?

Thanks.

[SVSooke]

Steve, which arm would that be? Can you replace the arms with those from the 550/650 rack?

Thanks.

The arm Steve means is the lower arrow.Can't just put a different one on because the carb spacing is determined by the bar the upper arrow is pointing to.
OK ,just looked at my spare carb set.You MIGHT be able to use a set of BS32's from something else by using the arms and spacers from a 550.Getting it all off could be more trouble than it's worth though

[Samiam]

thanks for the help!

[Steve]

Steve, which arm would that be? Can you replace the arms with those from the 550/650 rack?

The arm Steve means is the lower arrow.Can't just put a different one on because the carb spacing is determined by the bar the upper arrow is pointing to.

Several things would need to change.
1. You already have the mounting bars, they determine the spacing between the carbs.
2. The throttle shaft on either #2 or #3 needs to be changed (I think it's #2).
That is not easy, as you have to remove the screws holding the butterfly to the shaft, and they are swadged into place.
Actually, getting them out isn't so bad, it's getting them back in and re-swadging the ends so they can't fall out.
3. The "choke" linkage needs to change, but you should already have the short one.
4. The fuel "T" also needs to change, once again, you should already have the short one.

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