Q: Hello to you all. Please can you help me with a recent issue regarding my 1984 Suzuki GSX750?
I’ve owned this bike for the best part of my life and it has over 80,000km on the clock, I say over because the speedo broke about a year ago, but that is not why I’m writing.
My wife and myself have been on many trips with no problems, and the bike has always been serviced at the correct intervals. But recently when the bike is in top gear, and after a few kilometers, the bike just dies. I then have to shut off and rev the engine until it begins to run smoothly again.
I’ve fitted a new air filter because the old one is, well, too old, and drained the carbs by undoing the screw under the float bowl. I also fitted new spark plugs, but the problem still remains.
So please can you tell me what to look for next because we still want to keep the bike because we still enjoy it and don’t really have the money to buy one of these new and too complicated expensive machines?
Korbus (and wife).
A: It might be time to have someone, who’s a qualified mechanic, to take off those carbs and give them a thorough overhaul and service. You can still get some genuine parts from Suzuki, if you need them.
However, bikes of this age can generate problems with the vacuum fuel tap. If the diaphragm inside the tap is worn or leaking it will certainly starve the bike of fuel in a manner you’ve mentioned. There are vacuum tap rebuild kits for sale on the Internet, so check that out by taking the tap off, dismantle, clean and inspect it, and also the internal screen filter as well for blockage.
Another thing to easily check is the breather for the petrol tank, if blocked or restricted this will also cause this issue. So take of the fuel cap, strip it down, blow through all the parts with an airline, and see if that helps. Push the bike backwards and forwards to swill the fuel around and make sure you can hear air escaping from the filler cap to make sure it’s functioning correctly.
Go through these recommendations and I’m sure your loved machine will be fine again and give you many more hours in the saddle, with your wife of course.
