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notorious_jay
25-03-10, 11:13 AM
Hello all! So the GPz still aint running as well as she should. I pulled the carbies out and gave them a good clean but am still having some starting issues. about every 4or5 times after the bike has sat over night or a few days she wont start, Can sit there for 10 minutes trying (hoping the battery wont die!) and not even a gurgle. Its a fuel issue i think as the starter is going but it just wont fire. Then i leave it for an hour or so, come back and it will start (some times, other times will start the next day).

Was chatting to a mate and we think it might be the Prime isnt filling the bowls or something like that as there is no fuel off position.

Any idea's?

thanks
Jay

Mithel
25-03-10, 11:35 AM
Don't know the gpz but have you checked the vacuum hoses going to the tank. Are you starting choked or unchoked?


Another issue I had with the ZZR, i hope it isn't the case here. Symptoms were as you describe, problem was the head. As near as I can figure the intermittancy was the position of the piston and how much oil got in while it was standing. Some days it would fire up first time, others only after almost flattening the battery, and others fine after leaving it stand. This might be a complete furphy, but have a look at the plugs and see if they are fouled.

Kopfjaeger
25-03-10, 12:36 PM
the petrol tap is a diaphragm type tap. if it isnt coming out when on prime you have an issue there. works back from the cv carbs via the smaller fuel line to the tank. funky stuff with back pressure. could be your fuel as you say isnt reaching the bowls. start with the basics and work forward. check the fuel tap ( careful the screws holding the diaphragm in place strip easy. also check your fuel hose doesnt kink, i put a longer one on my 750 and that wasnt fun riding a km then stopping. if still stuck short i have the OEM manual for the gpz 900 r and the 750 supplement

Kopfjaeger
25-03-10, 12:39 PM
o and isnt it fun removing the carbs? he he he used to have to remove the thermostat to get the buggers out... and lets not talk about getting those springs on number 2 and 3 carb manifolds once all in place...... but i do miss my gpz 750..... 268k/hr, not bad for a 25 yr old stock bike

loopie
25-03-10, 04:03 PM
o and isnt it fun removing the carbs? he he he used to have to remove the thermostat to get the buggers out... and lets not talk about getting those springs on number 2 and 3 carb manifolds once all in place...... but i do miss my gpz 750..... 268k/hr, not bad for a 25 yr old stock bike

268 kmh out off a 750 what gearing are you running???, my rx even new in 86 would be hitting rev cut out about 250, the zzr 1100 c1 i had just reached 265km by the speedo, but i love theese old gpz,s ..... kawasaki still do a fuell tap rebuild kit for them, just done mine about $50.. bucks

notorious_jay
25-03-10, 04:21 PM
Excellent guys! this is great start for me.

Loop where did you get the rebuild kit?

thanks

J

Roninja
25-03-10, 05:07 PM
Have you confirmed that you have quality spark? I had the same problem when i bought my GPz900. Rebuilt the filthy carbies & rooted fueltap only to find the starting fault was the pulser coils going open circuit.

Arrne08
25-03-10, 05:17 PM
... Then i leave it for an hour or so, come back and it will start...


This is often a sign of flooding- something that is surprisingly hard to do under normal circumstances.

Does it need to be an hour. How about ten minutes?

Assuming you have spark, the first thing I'd try is:
- Crank the bejeeses out of it with full choke for say thirty seconds total (use short 3-5 second bursts so as not to cook your starter motor), maybe a bit longer. If you can turn the ignition off at the kill switch and still crank it, do that. The aim here is to prime/flood the engine.

- Wait about thirty seconds.

- Kill the choke and open the throttle WIDE. (We've put lots of fuel in, now it's time for LOTS of air). Crank normally (two to three second bursts) and see if there's a sign of life. If it does catch, it shouldn't run away on you before you can close the throttle to something a bit more reasonable. (This bit is the technique for starting a flooded engine; the alternative is to wait for while...)

Play around with the times, I must confess I do it by feel, not with a stopwatch.
This technique will start most reluctant carburetted engines, most times. It's what we used to do before Aerostart and SYB were household names.

One thing to remember here is that when the bike is cranking it is sharing the battery between the starter and the ignition. Just as you let go of the button, the engine is still spinning but the battery is only driving the ignition and you get a much stronger spark on that last half rev or so. This is another reason for short bursts of the starter.

Also, try releasing the starter at different parts of the cycle. Dependent on the configuration and type of crank there are better and worse times for the engine to catch.

Kopfjaeger
31-03-10, 12:15 AM
was a grey import GPz 750 r same colours as the 900 r in the red/silver. believe it was standard.268 was in 6th gear at 8 grand......on a back road near mt glorious.... tee hee,

Kopfjaeger
31-03-10, 12:15 AM
my 1000 gpz only does 248. sad but true.

Jimbo75
31-03-10, 06:05 PM
Have you confirmed that you have quality spark? I had the same problem when i bought my GPz900. Rebuilt the filthy carbies & rooted fueltap only to find the starting fault was the pulser coils going open circuit.

A mate had a similar problem and a new coil fixing it

notorious_jay
01-04-10, 01:44 PM
Great ill be sure to check these all when i get the change to work on her! Long weekend is looking good!

notorious_jay
13-04-10, 02:41 PM
eerrgh! So i pulled the tank off, drained it, cleaned it out, pulled apart/rebuilt the tap & lines, pulled/striped/soaked/cleaned out the carbies and made sure all was fine. Reassembled and put some fuel in and primed the bowls. Fired her up, was a little hard to start a first but was running like a dream on all 4. Road her up for about and hour and a half (was a little ruff but running!) them let her to rest for the night. Next day started her up no problems. let her run for 10 and shut her down. Day after, different story. Back to 1st base. starter is going, but she's not firing. tried again last night, and got a few little glurps out of here then nothing again!

errgh! i cant seem to think of anything else other than shes just constantly flooding or its electrical...

Chunked
13-04-10, 02:52 PM
Then it's either the air filter's clogged or you may have dodgy spark...

notorious_jay
13-04-10, 05:31 PM
The Battery is fully charged and i gave the air filter a good clean. Starts some days, some days nothing!

Chunked
13-04-10, 05:48 PM
Have you tried new plugs and checking the spark?

notorious_jay
13-04-10, 05:59 PM
Its 4 new plugs. checked all the lead lines ect, havent checked the actual spark yet though.

KitsuneStarwind
13-04-10, 07:03 PM
Are the pickup coils ok? possibly CDI issue?

notorious_jay
13-04-10, 08:49 PM
So i just tried her again, nothing. tried every combination of open throttle, closed choke ect. tested both the 2 outer plugs and there is spark, not huge, but its there. am thinking that the battery might be no good anymore. going to try having it hooked to a car battery and see if she starts tomorrow night...

Chunked
13-04-10, 08:58 PM
if it's not sparking very well outside the cylinder it's not going to spark AT ALL in the cylinder.

notorious_jay
14-04-10, 09:57 PM
So, the plot thickens. it appears to be a flooding issue. After hooking her up to the running car (as the battery went flat trying to start it) and trying to start her for about 20 mins if closed throttle/open throttle choke on/off combination i was about to give up, so i let her sit for about 10/15 mins still hooked to the car charging. then, still hooked to the car and the choke it, hit the GO button and she burped! burping on and off for 15mins (if i held the throttle open and tried it did nothing), she still just wouldnt fire. then just gave it a tiny little bit, rocking it on and off, she started! and took her for a ride!

now ill hope to see if she starts tomorrow. I have no idea whats happening, as she just appears to be easily flooding herself rather badly....

any ideas?

Doctor Shifty
14-04-10, 10:51 PM
An idea as I read the earlier posts, not a fuel issue, is that the plug boots are failing.

If you have never replaced them, do so now. Should be less than thirty bucks for the four. My old 1981 Suzie GS1000 was failing as you described - would sometimes start easy, other times not. I replaced the boots, everything was fine.

I was on a GS list when I had that bike (up to two years ago) and got the advice to give the replacement a try. Lots of other GS riders on the early bikes found the same thing.

notorious_jay
15-04-10, 01:45 PM
yeah, im just not too sure. Started this morning fine, rode her to work with out a problem and now 5 hours later on lunch break she wont start!

jefflthomas
15-04-10, 11:50 PM
shouldn't hook up to a RUNNING car

btw...how old's the battery