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Bad Flat Spot

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Garry.L
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Bad Flat Spot

#1 PostAuthor: Garry.L » Sun Apr 20, 2014 7:18 pm

My standard Z1000A1 has a proper bad flat spot around 4K revs, to the point it feels like it's going onto reserve (severe pulling back) if I try and hold these revs. However if I open the throttle further it easily revs through this flat spot.

Also (related?) the bike is VERY slow to warm up, ie even after several miles it can still bog down and pull back. Also (again related??) the bike seems a little 'Too' good on fuel?.

All consumables are new, ie plugs filters etc, carbs have been balanced and shims checked. plugs look the right colour, ie light brown etc.

Any thoughts?.

Ta.
Last edited by Garry.L on Sun Apr 20, 2014 8:01 pm, edited 1 time in total.
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tlc
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#2 PostAuthor: tlc » Sun Apr 20, 2014 7:31 pm

Garry.

Did you put the original coils back on?
It sounds very like the problem I had before I changed them.
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Garry.L
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#3 PostAuthor: Garry.L » Sun Apr 20, 2014 9:09 pm

tlc wrote:Garry.

Did you put the original coils back on?
It sounds very like the problem I had before I changed them.


She's still running the coils that were on I got her from you Chris....

Feels more fuel related to me, perhaps running too weak/starvation, but If I don't have any joy I'll try swapping them over (Are the set you gave me Ok?)

Cheers.
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#4 PostAuthor: tlc » Mon Apr 21, 2014 7:28 am

Well I wasn't sure Garry but kept them just in case. You could bench test them if your dealer still has a coil tester I suppose.

I agree it sounds like fuel. It usually took a couple of miles to warm up.
Could it be the pattern fuel tap or have you now changed that?
Also I found the mixture screws were very delicate and had to change a body in the past. Perhaps a check there. Also the choke mechanisms. All parts were replaced but with keyster parts supplied by z1 enterprises.
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#5 PostAuthor: Pigford » Mon Apr 21, 2014 8:32 am

Could try raising the needles a notch - or even going up a size on the pilots :?:
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#6 PostAuthor: Garry.L » Mon Apr 21, 2014 7:12 pm

Pigford wrote:Could try raising the needles a notch


From everything I'm reading/hearing this sounds like the answer....

:wink:
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