34mm PJ Keihns - are they any good

[scooble]

I have seen several 34mm Banshee Keihns for sale now and again, are they much different in design from the PWK35's (also used on Banshees)?

seems you can get them for a 'reasonable' price.
If the choke diameter is only differnt by 1mm seems like might be a viable alternative option - any thoughts?

[KR-1R]

my opinions...

PJ carbs were the design from 80's
which evolved into PWK series (90's and still OEM fitment today from KTM's to CR to KX, RM YZ...)

the main difference is the shape of the throttle slide - parallel (PJ) vs PWK (crescent).
PWK offers additional tunability in the cutaway on the slide to tailor the A/F ratio (be aware indiviual slides are expensive US$50 each only really serious race budget, most will choose 6.0 slides)

SO ON WHOLE, PWK CONSIDERED SUPERIOR IN TERMS OF THROTTLE RESPONSE.

ebay prices US$250 (PJ) pair vs US$350 (PWK)? = get what you pay for.

IF youre going to pick the route no one else has gone down (or can help you tune) then is second hand RGV Mikunis an option (which may have who knows what tampered with drilled out) (?which were tunable for main jet etc on removal of slide alone? rather than having to yank whole carb out?)

Can you afford for an engine rebuild BANG while you experiment - the extra $100 spent is in fact a saving on a rebuild. Also, is it peace of mind that youre UPspecifying the factory 'R' route rather than backyard mechanicing - if you ever go to sell you can say 'R' spec big carbs in confidence.

Those here running PWK35 have either bought ex KX125H1 (1990) or KDX200 (1990+ 1996 and later KDX were Air Strikers) second hand (a pair for 25% that of new price?) or new ones.
WAKI went on Air Strikers which really only differ from standard PWK in the small venturi fins in the throat and additional vents (mud blockage)

the PWK35 fitment on the KR is pretty tight (space below carb)
the total height dimension PJ(34) is 174mm and for PWK(35) is 163.3mm
so you ITS YOUR GUESS as to whether PJ's will even fit!! probably most of this dimension is above the throat of the carb (throttle pull clearance) but I cant be sure.

Youre main headache after choosing bigger carbs is finding/fabricating the rubbers that attach onto them (engine&airbox)

[scooble]

thanks for the comprehensive info!
All things considered, I'll probably get a set of PWK's when I can, (although I have always been keen on a bit of experimentation - I'm onto my 4th modified seat unit!)

[Tripitaka]

If the choke diameter is only differnt by 1mm seems like might be a viable alternative option - any thoughts?

I seem to remember reading that the PJ uses the choke mechanism as the idle speed adjuster.

Which would mean that you have to leave the chokes as they are and having two independent chokes to contend with every time you start up may be a pain in the harse.




Neil.

[mgtkr1]

pwk 35 the way to go. for above reasons and also agree that you can honestly say it has the same carbs as the kr1r. not important but a bit of kudos added to the fact that we know they will physically fit.

[KR-1R]

RGV mikunis was a dumb suggestion... due to the dangle angle