Motorcycle Repair: 82 suzuki gs850, calibration curve, plug caps

Question
i have a gs850 that onlt runs on choke but will idal iraticly with choke off carbs are spotlesss all jets are clean but air box is off does it need air box to run properly?

Answer
Waylon, there is a website called www.gsresources.com I think that specializes in these bikes.

Sounds like you have an air leak in the manifold connections or the ignition timing is off. Could also be bad spark plug caps, too. If carbs are good, then it should idle properly, unless the valves are tight or you have compression loss issues.

Off idle leanness is probably normal with air box connected, once you take it off, the whole fuel calibration curve is affected. You may have to put some washers under the needle clips and/or put bigger main jets in the carbs. Changing the exhaust system will also require jetting changes.

Bill Silver