PLEASE HELP AT MY WITS END GSXR 400 SP (none starter)

[martinstephensons]

HI all
i have recently bought aa none starting gsxr400 sp 93 on a kplate gk76a model. would not start at all when i bought it as battery was dead. replaced the battery and still wouldnt start so checked plugs and 3 out of the 4 plugs where knackered. replaced plugs and all fire ok. bike still wont start so striped the carbs and cleaned all jets. bike still refusing to start. i have had it started twice and it sounded really nice when reving but would only tick over at 3000 revs, any lower and it would just cut out. at 3000 revs it was surging up and down from 3 to about 4000 revs. checked plugs again and all fine (fuel is getting through to the plugs ok). This bike is in mint condition has had only one owner from new who had the whole carbs balanced and replaced all jet rubbers and everything back in 2008 and has just been stood since then. i have replaced the fuel so its not the fuel that has gone off just not mechanically minded so not sure what to do next. please help anything will be much apreciated as getting close to just stripping the hole thing and selling it for bits but would be a great shame to do. i live inbetween bradfor and dewsbury but any help either someone taking a look or just through messaging many thanks in advance...

[CMSMJ1]

Welcome to the site..

O rings...That is all..

One of the GSXR regulars (Mr Variable Valves Suck) will come and sort you some of these out and you will have a working bike...to note, was tough to read your post - stick some spaces in and perhaps a sneaky line break.

Like so.

So it is easier to understand

This is the place to be for getting your bike sorted...so chill, have a read of the other users issue and I am sure that your problems will make sense

[martinstephensons]

many thanks for the reply!!!

where is the best place to get the o rings from??

have read a few of the the other messages on here but most never seam to leave a message when they have sorted there problems.

[cruicent]

Variablevalvessucks on here sells them, hes on ebay too under a different name I think, £11 or £12. Or are the sp ones a little different? He said the jet rubbers were replaced in 08 would they have dried out again this quick?

[stripes1976]

depends on the quality. But definately carbs.

[martinstephensons]

depends on the quality. But definately carbs.

done the o rings in the carb but now there is fuel in the carbs but the plugs are bone dry.

ANY IDEAS ANYBODY????

[stripes1976]

what settings have you used? Also did you use box carb cleaner inside the carbs?

[martinstephensons]

The settings for the idle screws were 1.5 turns out which is what they were before taking them out. but there is no fuel getting to the plugs at all.


Yes when the carbs were cleaned they were sprayed with carb cleaner including all jets and idle screws and then blasted out with the air compressor.

Just out of curiosity there are 2 fuel pipes that go to the petrol tap 1 (1 at each side) and the vacuum pipe that goes to the end of the petrol tap and into the carb. Then there is a pipe that is attached under the petrol tank by a metal pipe like thing that is attached to the tank this doesnt attach to anything is this correct and is it a breather pipe. many thanks.

[martinstephensons]

LOST ALL INTEREST NOW STRIPPING FULL BIKE AND SELLING BITS IF ANYONE NEEDS ANYTHING FOR THERES JUST LET ME KNOW.

[Variablevalves suck]

Hi Martin,
You sure you going to strip the bike out as you will be left with loads of stuff.
The bike woz running so so and then you changed the o'rings (did you get them from me?) now the bike dont run.
Did you change anything else at the same time? If not-
Its clear that there is a problem with the carbs- it ran before they were removed- so this is the place to start.
First, have you connected the vacume pipe correctly and have you put the pilot screws in correctly- o'ring, washer, spring and then screw as if wrong gives this symptom. Did you remove the floats and are they as factory settings?
You usually find its the slightest of things that give major problems with carbs.