Bandit GSF 400
 

Good morning (pls excuse my English), I have a Suzuki bandit 1991. We had difficulties having it start after the winter. So we change the sparkplugs and she finally started. but now there is 2 of the 4 cylinders that do not work. We have cleaned up everything where the sparkplugs are connected because it seems to have some humidity there, but they still don't worked. My friend is very good with bike, but he is out of idea on what to do.

I would like to repair her myself and not bring her to a mechanic, so is there anyone who can give me an idea of what I can do to have those 2 cylinders to work?

Thank you

Info??
 

Little more information! What was done to the bike before it was shut down for the winter, where was it parked, indoors or out?
Norm

won't start
 

Drain the carburators, on the bottom of each carb is a screw.....loosen it and gas should run out. That gets rid of that stale old gas. Then check if the center two or outside two cylinders are not running. Most japanese bikes spark the outside two cylinders and the two inside cylinders together. If just the two left hand cylinders are not running than you might just have plugged up carbs. If the outside or inside set of cylinders are not running you probably have a electrical problem and it is time to get a shop manual and do some more tests. How to see which cylinder is running on a 4 cylinder bike? Lightly touch the exhaust pipe for each cylinder to see which ones warm up first. (don't try this after a ride. Or if you do check the link under 3rd degree burns!)

bandit
 

I live in Laval (Québec), it was stored in a shed in my back yard and nothing has been done before putting her there for the winter.

When changing the sparkplugs we found out some humidity in 2 of them that is why we opened it and clean everything. Still the 2 right cylinders won't work!

OK First thing to do is as bill said "Drain the carburators", also check the fuel tank to see if there is water in the bottom. Condensation will form in the tank over the winter! Do the spark plugs on the dead cylenders have spark. Remove plugs and hold to the side of the engine and crank engine over you will see the spark between the point of the plug. Let us know what you find

Hi Bill, you going anywhere this year? Maybe stop in and see you again, first of July, on my way down to Colorado.
Norm from Calgary, Alberta

Non starting Suzy
 

Here in montana we deal with a lot of non starting bikes after sitting during the winter snows. We drain the tank and start with fresh fuel and flush that thru the carbs. We also install new spark plugs just to be on the safe side. Then make sure the battery is fully charged or replace it also. Hey Norm do stop in...but I won't be working at the honda/yamaha shop anymore. I am changing jobs and am excited about it. The door is open for travelers passing thru and I should be home this summer except for weekends (I have to build up some leave time and good graces).

How's about checking the obvious: are the plug leads on the right plugs?

Try swapping over the two non-working plug leads.