Needles !!!

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headcoats
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Needles !!!

Post by headcoats »

The KR bikes had a few different needles over the models like 99E and N68 etc but what are the different dimensions

Taper
length
Diameter
Can it yer old boiler
headcoats
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Post by headcoats »

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Can it yer old boiler
KR-1R
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N68A vs N68X PWK28 needles for KR-1

Post by KR-1R »

the overall needle Length = 57mm

used dial vernier (so rough and no 99's handy to measure)... by looks...
N68A = 2.435 mm dia but is 'Twin Taper' - see Sudco specs ~= JJH or maybe JLH (they are NOT 2.75 dia 'HarleyD' needles as quoted elsewhere)
N68X = 2.395 dia ~= JJD
... so needle N68A is slightly leaner than N68X all the way along its length (at corresponding points N68A being around +0.05mm more diameter against N68X)

JJH (Taper, L1, Diameter)
length (overall) = 57mm needle
Taper = 3°
L1 = 25.4 mm
Diameter = 2.435 mm

people with Banshees/blasters etc seems to like the N68A (twin tapered) more the JJH

have you tried somebody elses 28 carbs? compared with yours
youve gone 2 screws out on 45 pilots so why havent you gone bigger pilots still?
headcoats wrote:I went to #160 mains in the summer and lost 4.5 BHP and it wouldn't rev over 9 grand,so went back to 152's

Anything less than #45 pilots i get a horrible jerking on light throttle and only going up on the pilots seemed to cure it

But i guess the thing i need to know is about these fabled JJH needles :-({|=
if youre running problem is less than half throttle it wont be mainjet related >>> Pilot >>> Needle (dia...clip...taper) >>> Mainjet


Image
...visually - difficult to tell these two apart



there is a typo error in diagram below
if the needle is 2.435 dia if cant be 2.515mm further along the taper...

Image
Last edited by KR-1R on Mon Feb 28, 2011 11:56 pm, edited 1 time in total.
KR-1R
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Post by KR-1R »

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headcoats wrote:I have bought some needle shims for my PWK carbs and when they arrived they just look like normal washers :evil:

One measures 0.71mm and the other 0.59mm :?

For these clips to lift just half a clip position what thickness should they be


...pretty much half of 0.9mm for half a clip
= 0.45mm
Last edited by KR-1R on Mon Feb 21, 2011 11:24 pm, edited 1 time in total.
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