Flat Spot

Twangled your powervalve grommit in your woodruff key? ask someone how to fix it here
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Steely
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Flat Spot

Post by Steely »

Hi there!
Took the KR-1S for a spin today, first time it has been out for a while using full power, full engine rebuild done, it has also been set up on a dyno.
I found that it has a quite bad flat spot at around the 5000 rpm mark and if you get caught up in it the bike really bogs down.
When you get over the 6000 rpm mark it then goes like stink, is this normal, i can't remember if it did this or not before the rebuild.
If you really nail it from low revs it misses the flat spot and just gets on with it, taking off like a rocket.
If anybody has come across this could they please put my mind at rest, really worried that i have it set up wrong.

Many thanks, Tony
Cliff
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Post by Cliff »

I've owned two KR's (one currently) and both behave exactly like what you describe. As far as i'm concerned it's normal for the KR.
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JanBros
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Post by JanBros »

jep pretty normal, allthough on mine it's always been arround 6.000.
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the-elf
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Post by the-elf »

are you lot telling me that you can ride a KR at below 9K :? :lol: :lol: perhaps I should start riding on the road again :wink: :wink: .
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col
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Post by col »

mine was between 6-7000rpm.
its normal.
you might want to try checking your valves are set up properly and opening/closing to the right positions when they activate.
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JanBros
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Post by JanBros »

the-elf wrote:are you lot telling me that you can ride a KR at below 9K :? :lol: :lol: perhaps I should start riding on the road again :wink: :wink: .
then you've got a bad engine :twisted: a good KR1 engine (even tuned) should start spitting out horsepower from 7.000 :!:

mine starts at 7.000, a little bit less than a standard engine, but gives another big boost at 10.000 :wink:
My ultimate goal is to die young as late as possible !
sacko
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Post by sacko »

Mine was exactly the same too. Tried running the needles at the top setting and that cures it completely. Since I had my rebuild though I have been running it at standard setting as I don't want it running lean and its back with a flat spot between 5-6k :D

It only really gets the flat spot if you sit below 6k for a while though so just ride in a lower gear, it sounds better then too :lol:
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Steely
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Flat Spot

Post by Steely »

Hi

Thanks to everyone for the info, put my mind at rest, i think i must be a bit nervous about riding through town in a low gear, a lot of beady eyed coppers around here.
It does sound a lot better though, what the hell, let's go.
mj43
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Post by mj43 »

Steely

If you are only in Rugby pop down and see me and I will give the bike a once over.

I live in Stockton nr Southam.

MJ
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