Mechanical to Vacuum Carb Swap

[KrazyKarl02]

Ok, so here is a question. I have 2 GS 1000s One is an 81 that is beat up and in bad shape. The other is a 78 that I can not get the carbs tuned properly. The 78 has the older mechanical carbs and the 81 has the newer vacuum operated carbs. Can I swap the vacuum ones to the bike currently with the mechancial carbs? I realize there might be a problem fitting the air box in, but other than that any thoughts? Anyone done this????

-Karl

[Billy Ricks]

Shouldn't be a problem. If the petcock on your bike doesn't have a vacuum fitting just plug the fitting on the carb that supplies vacuum for it. Most carbs will deliver the right air/fuel ratio on any bike as long as they've been tuned right to start with and the motor is in the same basic state of tune as the donor motor. You may have to tinker with jetting a little.

[SqDancerLynn1]

The only problem would be the intake boots are a different size. You may be able to make something type of adapter with auto radiator hose. I don't know if the 82GS boots will fit on your 79GS head. Anything is possible. I would compare the boots.

[KrazyKarl02]

does not work

well I finally tried swapping carbs, and there is no way that this idea would work. The rubber intake boots are different sizes, so I figured I would swap those too. Well it is not just the rubber poots, the intake on the head is 2 uniquely different sizes with a different bolt whole pattern.....

Guess I am back to tuning mechanical carbs.....