Flat spots at full throttle

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geoff c
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Flat spots at full throttle

Post by geoff c »

Hi
I have recently stripped, cleaned and rebuilt the carbs on my 1990 1000exup. I have replace all the seals, new jets, inlet rubbers and airbox rubbers and new plugs.
After balancing the carbs she sounded really smooth and very responsive.
However when i took the bike out for a run it picked up really well upto 7000rpm then hit a flat spot until 8000rpm then took off again until 10000rpm when it hit another big flat spot.
Any ideas what might be causing this. The bike is completely standard, the exup valve is working fine and set correctly.
Thanks in advance.
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nuggitt
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Post by nuggitt »

Good. That rules that out then. :nod:
Bit of advice. Buy a good bed and a good pair of shoes, because if you aren't in one you'll be in the other.
geoff c
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Post by geoff c »

Checked the breather which was free of restrictions as is the exup movement.
I installed new airbox rubbers, should these be sealed with silicon or are they self sealing, clutching at straws here.
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Teego
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Post by Teego »

It's worth checking the 2 fuel filters.
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Scrinja
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Post by Scrinja »

Also worth checking the float heights Dude
geoff c
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Post by geoff c »

I think i may have found the problem, i have a small crack in one of the carb tops, although it doesn't appear to have gone all the way through. Does anyone have a spare they might want to sell?
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