Carbs/Power Valves

Twangled your powervalve grommit in your woodruff key? ask someone how to fix it here
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nickbee
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Carbs/Power Valves

Post by nickbee »

:D Just got my KR1S running after rebuild and for the first time as when I bought the bike I didnt hear it run. From looking in the manual it lists I think N68 needles but on my bike it has N99. Whats the difference and where should the circlip be positioned on them as currently they are in the middle groove.

The pilot jet is 40 and the main jet is 135 these are the standard jetting I think.

Also how much free play should the power valve cables have as when I turn the ignition on it opens and closes but there seems to much, then if you tighten them to much they wont do the full cycle of close/open/close.

Cheers

Nick.
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the-elf
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Post by the-elf »

If you look on the team sparrow site it gives the standard carb settings. Most people put the circlip in the top notch as its supposed to improve the mid range. I'm running KR1R 35mm carbs now and my memory is a bit slack on the standard needles but IIRC the NXX numbering system is Kawasaki's own numbering and is very different to the manufacturers numbering system.

Look on MJ's team sparrow site and on Allens performance web site and there is some info on the needle numbering system on both. Also someone posted a link ages ago on a site which had a converter to swap between the two numbering systems.

To set the power valves up drop the exhaust, switch on and once the Powervalves are open switch off the ignition and using a torch adjust the cable so that they aline correctly with the port when open (the closed position is alot less important). Also the PV cables require regular oiling as the heat from the engine can dry out the cables and cause them to sieze.
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KR-1R
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Post by KR-1R »

the original needles were
the KR-1 (B) needles were Kawasaki N68A
the KR-1S (C) were N68X

second notch from pointy end

if its pulling through the entire rev range without coughing the needle should be fine - you never know if someone hasnt machined the diameter or taper etc

play with clip position to see if pulls a bit harder going rich (lower) then lean position (higher clip)

dont go smaller than 130 mains (stock B model) 135s are good in either B or C models
nickbee
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Post by nickbee »

:D Thanks for the info will try at weekend if not snowed in!!!

I had a look on the team sparrow web site and listed my needles + jets matched a C3 model. How do i tell its a C3 model?

My bikes black & green and a 1990 h reg.

Cheers

Nick.
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Post by KR-1R »

you can tell the model from the chassis number stamped on the righthand side of the steering headstock between the fork triple clamps.

some THROTTLE advice...
make sure there is sufficient slack in the throttle cable adjuster (as it comes out of the twist grip)...

there should be AT LEAST a good couple of mm play in the twist grip before any movement of the carb slides and certainly turn the bars left and right to see if if alters any pull on the cables/idle

if the throttle cable is incorrectly routed (around the forks and over the engine) cable tension can be affected (it can open the throttle slides when turning a corner (low speed) etc UNSAFE blah blah) .

too tight and all sorts of running symptoms may appear - lean idle (slow to rev down). Might make you think the needles or jets are wrong.

You wouldnt take ALL the play out of your clutch cable, why would you do it to the throttle?
nickbee
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Post by nickbee »

:D Thanks for the info about the throttle cable, i must admit i didn't think about that.

Cheers.
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