[shadetreegixxer]

I just purchased a 93 gsxr 750 and I can not get it to run. It ran fine for about ten minutes when I went to pick it up and after unloading it at home it decided to guite running. I have done the normal checks like carbs, ignition, and so on. I did a compression check on the motor and here are the results.

CYL1 = 80#
CYL2 = 82#
CYL3 = 85#
CYL4 = 85#

I think these are very low numbers but I am not sure. I believe that they should be in the 160 range but I have not recieved the manual that I have ordered yet. Does anyone know what the stock compression numbers should be?

I also noticed a little gas in the oil which can effect compression but do not have any base numbers to work from.

Also if these are as low as I think they are, would this keep the engine from running? Currently all i get when I try to start it is a very loud exhaust backfire(using choke) and a few good hits along the way.

Any help would be most appreciated.

Thanks

 

[pitbull76]

Shadetree,
Change your sparkplugs!!! I had the exact same problem with my GSX750 Katana. I started it for a few minutes, but didn't totally warm it up (when inspecting the bike to purchase it). When I went to restart it, all it would do was backfire. I called a Suzuki dealer and he told me he was almost certain that I had fouled the plugs. He said it was quite common after starting it cold and not letting it run long. I replaced the plugs and it fired right up. Your engine may still have a compression problem, but if it ran before and is backfiring now, the plugs are probably the reason that it won't start. Good luck.

 

[shadetreegixxer]

Plugs did the trick. I also changed the oil. Fired right up. I think the carbs may need sync'd but it is running good. Thanks for the wake up call. I had considered the plugs but never gave it a second thought.


Thanks