GPZ900R

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bikeral64
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GPZ900R

#1 Post by bikeral64 » Fri Sep 25, 2009 11:39 am

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.

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joecrx
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#2 Post by joecrx » Fri Sep 25, 2009 1:52 pm

poor spark ,or not enough air when choke is on

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Samray
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#3 Post by Samray » Fri Sep 25, 2009 3:35 pm

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

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bikeral64
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GPZ900R

#4 Post by bikeral64 » Fri Sep 25, 2009 4:24 pm

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.

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bikeral64
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GPZ900R

#5 Post by bikeral64 » Fri Sep 25, 2009 4:26 pm

joecrx wrote:poor spark ,or not enough air when choke is on
We will look into that one!

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Samray
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#6 Post by Samray » Fri Sep 25, 2009 4:35 pm

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. :smt012

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Kwackerz
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#7 Post by Kwackerz » Sat Sep 26, 2009 3:58 pm

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?
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Kwackerz
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#8 Post by Kwackerz » Sat Sep 26, 2009 3:59 pm

And Sam, crap in the tank.. understatement! more crap than fuel I seem to recall... :smt002
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#9 Post by MartDude » Sat Sep 26, 2009 5:57 pm

Samray wrote:, till I got crap in the tank. :smt012
Were you taken short?
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bikeral64
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Re: GPZ900R

#10 Post by bikeral64 » Thu Oct 01, 2009 7:41 pm

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.

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joecrx
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#11 Post by joecrx » Thu Oct 01, 2009 11:23 pm

check valve clearances

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