My gk76

[bayz]

Hi i recently got a non running gsxr 400 gk76, cant remember if its a 92 or 94 but its one of those lol..

after cleaning the sticky carbs, putting new spark plugs, and new oil i managed to finaly start it, but.. it refused to rev up.. and after a bunch of test and a few other opinions we figured out that the cdi was was messed up, and instead of firing 2 plugs then the other 2.. it sparked all 4 at once.. hence why it idled but wouldnt rev up as the firing time for amoount of fuel was wrong.. so ordered a new cdi, started the bike, and it reved up nicely.. the bike now even rides like a dream..

only 3 major problems im currently experienceing, 1/ is cold starting it in the mornings, i run the battery flat, then lift the seat and jump it from my ford ranger.. then it takes about another 2 mins before it will start.. i cant imagine this to be right..

i dont know if is could be leaky o rings, as the bike when it rides have no stutters at low rev nor hight revs, its clean throughout the revs

also i dont keep the starter pressed all the time at once,.. i press at for like 5 seconds per try..

2/ is my front disc seems to be loose it makes clicking sounds when im riding,.. as i dont know anybody else with a gk76 i cant compare to see how loose the disc should be on the dowels/ floaters

and at no 3/ my front shocks are leaking, ill be taking it in within the next week te be re sealed and re oiled, unless somewhere there is a dummy proof step by step way to do it myself..

i dont know much about shocks so i dot know what tools would be needed inside the shocks and all that, and if its difficult to do or not .. so i think im best of just taking it in..

any help or info would be highly apreciated
thanks

[dobbslc]

I've got a similar starting problem as you draining the battery but I have just found that the bike is turning over but the plugs are not fireing then suddenly it will start and run ok. I thought it was the carbs having a partly blocked idle circuit.
I have just found that there is a loose or broken wire somewhere under the clocks, I moved it and it started!???
The weird thing is is that once it starts it will run ok
Will look into this further tomorrow.

The brake disc's will have a little bit of movement on them back & forth / side to side as long as it's not more than 1 or 2 mm it should be ok.

I have just today done the seals in my forks (non sp) it's not to bad too do but the damper rod / top cap can be a bit of an arse to get back on. You will need a large vice. If you take the forks out yourself then take them to a shop it will save you 1 to 2 hours labour.
Hope this helps.

Dobbs

[bayz]

thanks dobbs, that sets my mind at ease regarding the front discs :D

interesting discovery you made there, i will look into this, but i doubt i have this kind of problem..

what it looks like to me is when i attempt to start it, it does in fact have spark because it sounds like it wanst to start the whole time on the exhaust, the exhaust doesnt sound as if theres no spark.. not sure how to put my mind into words there ..

so it seems as if with every burst of spark, it obviously ignites the fuel, which result te bike sounding like it want to start, but then it only goes on like this.. but then with each combustion it actually add a bit of heat to the motor until eventually after the battery is flat and im jumping it.. after 2 mins from jumping its hot enough to actually go and keep on going... (the entire process takes about 5-8 mins, maybe 10mins.. havent really timed.. but more or less)

im not sure if any of that babble i wrote makes any sense or if i far fetched my theory ...

dont know if my air fuel mixture is not right at the moment, when i cleaned the carbs i set the air jets on standard 2 and half turns open

besides for the air jet setting, heres what else is up with my air fuel mixture.. in the image bellow, the circled breather pipes is not currently connected to my airbox as i dont have these pipes.. im thinking of putting those small k&n filters on them ..


Uploaded with ImageShack.us

then the airbox self, the previous guy drilled 4X 10mm holes at the back, and the round filter is missing.. so for time being i just wrapped a piece of car upholstery around the fitting.. just to keep that extra dust particles out..

so i dont know if this all could be the problem, or might be part of the problem

[ben2306]

ever try pulling choke?

[bayz]

yes, i use choke on start, i actually alter between full choke and half choke every few presses at the start button..

i've even gone as far, as to have a go at the start button a few times, then priming the carbs a bit with the tank tap, and then switching the tank tap of after prime, and having a few tries at starting again.. .

when the bike does actually start on full choke, i leave it to heat up a bit before i close the choke,.. but that quite quick.. takes about 30sec after i get it to start, for the revs to start going up as it heats up..

also it idles at about 2000rpm when i close the choke.. some say it idles to high,

[dobbslc]

Bayz
I have just found a small relay under the seat that has something to do with the kill switch circuit, I replaced it and so far it's starting on the button
Get your carbs balanced then set the air screws to 2 or 2 1/4 turns out as it seems to let the revs drop down to idle quickly when set to that on my bike.
Also check or swap the coils as I had a duff one the caused all sorts of trouble like hard starting & poor running.
Dobbs

[bayz]

Hi dobbs

anychance you can put a pic up of the relay your talking about.. just so i can make sure i get the right thing ... also is your bike still starting every time now on the start button??

I did a test tonight out of curiosity to see if i can actually cold start the bike by push starting it ... so when i got home this evening, i pushed it outside kicked it into 2nd gear and of i went.. and it started rather quick if i must say.. after popping the clutch the 4th time it started ...

so now im confused as hell .. why does it cold start so quick when being pushed.. but when using the starter it takes up to 10 mins to start..

surely that is another sign that my o rings should be fine

and to you above post, the carbs has already been cleaned and sinced.. all jets are set out normal 2 and half turns out ..

[dobbslc]

When you bump start a bike it takes a big load off the battery helping to give a better spark. A faulty coil, bad earth or bad battery may cause this.
The relay is the one next to the indicator relay under the seat.
My bike seems to start ok now but seems to like the ignition to be turned on for few seconds first???
Don't know why.
Dobbs

[bayz]

i havent tried the relay yet.. im still trying to source one, or an aftermarket one to see if thatll work..
but right now im thinking of redoing the carb o ring, as of what knowledge ive gained from this site i came to a conclusion, just because you replaced something doesnt necessarily mean its fixed, think i might have pinched or cracked an o ring or two without noticing, didt lube them or take the proper route, just jammed them in and figured their good now

since i have my idle set higher than what it should be, by personal preference at 2k i never really seemed to notice the shaky very low revs.. so to day i figured ill just set the idle to normal 800 to 1k revs and se what happens.. i then noticed at right at the bottom its running extremely rich and shaky picking up..

i cant seem to find new o-ring set on ebay .. dont know if anybody on here knows of someone selling new o-rings..

[stripes1976]

your idle is too slow at under 1k. set it at 1200