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Any suggestions on how we can get our GPZ900R to start from cold. It starts first time on the button when it's warmed up, even when it's left for an hour or so, but when it's cold, it tries to start but just won't catch. Any throttle kills it dead. The choke is working properly, we have tried it in all sorts of positions 1/4,1/2, 3/4, no difference. The carbs are all balanced, new plugs, new cdi unit all new mains and needle jets and needles. Float positions checked. Goes like a rocket once it's started, no flat spots etc. Must be something simple, perhaps a GPZ900R owner has had similar problems. We hope to here from you all.

poor spark ,or not enough air when choke is on

Have you got the three position fuel tap? .. On, Reserve, and Prime?

Samray wrote:Have you got the three position fuel tap? .. On, Reserve, and Prime?

Yes it has got the 3 position fuel tap, we have tried it on all positions. We have also checked the vent in the filler cap.

joecrx wrote:poor spark ,or not enough air when choke is on

We will look into that one!

Thinking back, when mine was behaving in a similar manner, it took a new battery to resolve it and was no trouble after, till I got crap in the tank.

How did the problem manifest itself to start with? slowly over time or all of a sudden?

What ya got the revs set to for idle?

And Sam, crap in the tank.. understatement! more crap than fuel I seem to recall...

Samray wrote:, till I got crap in the tank.

Were you taken short?

bikeral64 wrote:Any suggestions on how we can get our GPZ900R to start from cold. It starts first time on the button when it's warmed up, even when it's left for an hour or so, but when it's cold, it tries to start but just won't catch. Any throttle kills it dead. The choke is working properly, we have tried it in all sorts of positions 1/4,1/2, 3/4, no difference. The carbs are all balanced, new plugs, new cdi unit all new mains and needle jets and needles. Float positions checked. Goes like a rocket once it's started, no flat spots etc. Must be something simple, perhaps a GPZ900R owner has had similar problems. We hope to here from you all.

We have been advised to do a compression check, this has revealed a serious loss of compression on the two outside cylinders. I think this might just be the problem. We will let you know in due coarse.

check valve clearances