KR-1S.co.uk Forum

is it me or am i being thick, thanks to a couple of kind people on here i sourced 3 pwk28s, top job really pleased.

when i look for main jets on the web i.e. splatshop they look totally differant to mine.

the mains on the parts diagram in the section below look the same as mine.

why the differance and where can i buy the proper ones

thanks

kez

If you can give us an example link it might help, but at a guess, they are probably for the larger PWK carbs.

Drop rocket a PM and he'll be able to sort you out some for your 28's.

Splt shop jets are the hex type for the newer PWKs and the ones you need are the round slotted type

Allens performance sell them

. there's 2 DIFFERENT types...T

OEM (standard) KR-1, KR-1S mainjet... OEM type round head (99101-393 series)



KR-1 = 130 main
KR-1S = 135 main
Kwak part... 92063-1013 ...JET-MAIN,#140
Kwak part... 92063-1015 ...JET-MAIN,#138
Kwak part... 92063-1014 ...JET-MAIN,#135
Kwak part... 92063-1076 ...JET-MAIN,#132
Kwak part... 92063-1075 ...JET-MAIN,#130

the AFTERMARKET (Sudco/Allens etc) version of PWK28 (from KX80/85) etc is the -357 series (hex head) and Not for KR - for big PWKs and FCR - different fuel bowl drains

thanks guys , it is the round ones i have and all 3 are jetted to 138's i wanted some differant ones to try as im still setting up the bike, and spares would be good before it goes to the dyno.

i will get in contact with allens performnce

I would keep the jetting standard unless you are racing or have severely tuned your motor.

.
.
http://www.allensperformance.com/keihinjets.html

^^^ just check your thread and head size on Allens in case I'm wrong on the part number series

I guess the two types can possibly be interchanged - after all isnt the jet submerged in the fuel in the bowl?

the common, long hex head mains (-357) are used on carbs that have the large fuel bowl drain bolt (aftermarket/KX65/85/125/250/500) - so on a Motocross bike the jet can be easily accessed and changed with little hassle (without removing the bowl) - the hex being more robust for tools (race bike) - whereas the slotted variety are more likely to be set and left for good (road bike)

Just remembered these are not on a KR.

the engine has had porting and custom pipes made and at the mo the carbs are on 138 mains




its not a kr1 your right but the carbs were the recomend of the tuner

Before you start buying random sets of jets from Allens (which aint cheap) hows the bike running, could have discussed this last Sunday

hya nick

it was its fisrt run out last week but to be honest it ran ok but not brill, quite bogged down between 4 and 6 thou but when it hit 7 fook me it took off like a scallded cat all the way to 10k.( the redline on the dial is about 8 )
as far as jetting goes mick abbey wanted std. pwks from kr-1 but they are stated as 135 mains mine are 138's hence my initial question on jet types

KR's bog down around those revs

It might be worth dropping the needles a notch or two first

As Said the needles play the the biggest part between 1/4 & 3/4 throttle so try dropping them a couple of notches to lean up the mixture. I wouldn,t try reducing the size of the mains or this may happen to yours what happened to mine on the way back from Bury Hill on Sunday. I forgot cold air leans up the mixture

Shit luck nick really sorry to hear that did it make it home or were you stranded.

on a brighter note if you had your triple you would still have two working cylinders

Blew up 100 yards away from a pub so had a couple of pints waiting for the recovery van to arrive