Gsxr750 running on 3 cyl

[Hendley]

Hi all, I have just joined the forum, I own a 1992 gsxr750m, It has just started firing on 3 cylinders I have isolated it to the second cylinder in from the left, I have changed the plug and tried new coils and no change but when I pull the plug cap off I can hear the electrical pulse in the plug cap so it's getting power, anyone got any ideas regards paul

 

[Rosie66]

Hi, is it getting a spark if you put a plug into the ht lead and ground it? if it is it sounds like a fuelling problem.

 

[Hendley]

Hi, is it getting a spark if you put a plug into the ht lead and ground it? if it is it sounds like a fuelling problem.

Hi yes just checked it and all plugs are sparking however it's down to 2 cylinders, the 2 outer cylinders are running, so the 2 inner cylinders mustn't be getting fuel so what's the deal with these carbs, any general issues with them, I have to say the bike was in an awful state when I bought it so I'm slowly getting it somewhere close to respectable but it has got 45000 on the clock, So it wasn't looked after, is there any think that packs up in these carbs that would cause no fuel getting through, I've been using the bike for about a month now so it's had plenty of clean fuel going through. Paul

 

[Rosie66]

Mikuni flat slides should be pretty reliable, I would take off the carbs strip and clean them, check the jets, float height, diaphragms etc etc. I assume the plugs on the 2 cylinders not firing are dry?

 

[Hendley]

Mikuni flat slides should be pretty reliable, I would take off the carbs strip and clean them, check the jets, float height, diaphragms etc etc. I assume the plugs on the 2 cylinders not firing are dry?

Hi, yes the plugs are dry, just thinking about it there has been a strong smell of petrol around the bike over the last few days, I will strip them and check them out, just seems strange the inner 2 are playing up.

 

[Rosie66]

 

[GSXR916]

have you recently run it very low on fuel?

get yourself an inline fuel filter.