Keihin carb

[stallion81]

Need to identify, and remove TORS, to replace(cable works, but might as well replace when doing brakes as has electrical tape at the lever). KEIHIN PWK

Got a 97 Blasty, carb is spilling all over(float?). Pulled the carb, and I cant Identify from the #'s on it.... 73RAB LC is on the carb, the motor side is approx 1- 7/8, airbox side 1 -3/8. Well I dont know how to get the cable out, as the carb is much different then the books. The carb has a 2 screw plate on top(tors), and the whole kit and kaboodle comes out(spring/sleeve/needle). Aso need to get the bottom off, to check the float valve. The 2 screws wont let it all out. Has a bottom nut(14mmish) but I havent removed it yet. Hoping for some help =).



Anyone got an old link to this kinda carb? The newer ones are definatley not what I have.

 

[slickerthanyou]

A pic might help.

 

[sicivicdude]

That's a keihin PWK 28.

 

[shawnsadler]

yeah sounds like a Keihin PWK... as far as size sicivicdude may be on the right track. i couldn't tell you. to get the cable out pull the top off and pull the slide out... pull the spring up so u have some slack and push the cable down and out the little hole in the slide. when it unhooks pull it up out of the top of the slide through the spring..... as far as bottom goes.. after the two screws are out.. pull the bowl down.. kinda firm.. there is a little angled rod inside that is a lil pain.. as far as the big nut on bottom. that is where you can change your Main Jet right on the bike. loosen the carb. Turn it till that nut is accessable. take the nut off.. change out the GOLD HEX MAIN JET put in your new size and put your nut back on.. turn carb back upright and tighten down. hope that helps.. if anyone has anything else to add that i may have missed please do. Good Luck

 

[98blaster+4]

when you loosen the screws does the top plate get a little loose? if so its kinda a pita to get the bowl off but it does come off with some careful persuasion. the big nut on the bottom is for main jet changes only not the pilot and shouldnt be olding anything together except itself to the bowl

get some pics for better instruction
what he said/\/\

 

[stallion81]

Thanks guys, I got it all figured out this morning. I still gotta pull the jets to see what size they are, hopefully they have the size stamped on them, like the ones for my S&S on my Harley. As for pics, I'll try getting some later.

The carb does have PWK stamped on it, but it looks exactly like the PWM. The tors is completely different between the PWK and PWM, from the pics I can find on the net.

The rubber tip on the float needle looks pretty worn. Thats probably where my overflow is coming from.

 

[sicivicdude]

There is no TORS on the keihin carburetors, only on the stock Mikuni.

The PWM's look limilar (from pictures on the web) to the PWK 28 because of the screw down lid.

That float bowl overflow tube can be a pain sometimes. Mine is always giving me fits trying to take it off.

The jets should be numbered but the numbers don't necessarily correspond with anything you might find in your harley. Kiehin "6mm hex" jets use a volume numbering system. All of the keihin "6mm hex" jets are usable in all carburetors that use them but they don't compare to other manufacturers strictly by the number.

Mikuni's numbering system is nearly twice what Kiehin's is. The biggest laugh is the dynojet numbering system which is almost the same as keihin's but just different enough to cause headaches... and possibly blown engines.

 

[cole454]

Mikuni's numbering system is nearly twice what Kiehin's is. The biggest laugh is the dynojet numbering system which is almost the same as keihin's but just different enough to cause headaches... and possibly blown engines.

Thats why I only buy factory jets.

 

[stallion81]

Dead on sicivicdude. Definatly a PWK 28mm. Well I pulled the jets, nothing stamped on the main. The pilot is 48.

I dont believe the engine is bored? It does have a FMF fatty and FMF silencer which I believe is powercore. Airbox is stock, had stock airfilter, but I'm using a twin air, with a no toil for backup on the stock cage for now.

The bike seems to run just fine. Very responsive, good throttle all the way thru. When 1st started, its idles down slow, but only lasts for 20 secs or so. Just pulled the carb to stop the bleeding.

I might tinker with it some more, when I bring it home to change the front end.

 

[sicivicdude]

48 is a might large for a stock engine with only a pipe. Have you ever done a leak down test on it?

Might be something to look into.

Anyway, the good news is, Keihin PWK 28's are relatively inexpensive and easy to get parts for. Main jets, float needles, and pilot jets are easily purchased from most motorcycle dealers which deal with dirtbikes too. The YZ85 and KX85 both used PWK28's and the pilot and "6mm hex" jets are used in various carburetors across keihin's line. You should find jetting relatively easy.

The PWK28 is a reliable and fairly robust carburetor

 

[stallion81]

=), I thought the same thing after I posted, was thinking RICH. Well I might have blown her up? Had the wife PU the float needle and sleeve, but my carb does not have a replaceable sleeve......

These carbs are about stupid, and they are smarter then my a$$ =). Well I learned that what I was calling TORS is the throttle connection. And the throttle lenght has to do with how the carb runs............... WHY DOES A CARB HAVE THROTTLE BUILT INTO THE GAS/AIR(when idling).

I guess I need to know how to adjust the trottle cable, basically the height of the slide in the carb body. Adjustable at the throttle, and the carb. Just new to making carb adjustments, with the throttle cable. How much open(slide) when the gas is not pulled(and then idle). This "slide adjustment", seems to have a big swing on how the bike fires, if it even fires.I can rework the jets, after I get it running.

 

[stallion81]

After doing more research, I'm thinking I may have damaged the slide or slide spring? The throttle cable was barely threaded in on both ends upon 1st removal(grip and carb side). With the carb in hand, and making cable connection adjustments, the slide would go further in the carb(closing), when screwing in the cable ends deeper, and further out(open) when loosening cable connections. I would assume those would be for "cable stretch" adjusting.

I guess what I need to know is correct slide operation. Should the slide go thru a full range, fully open to fully closed, when on or off the throttle?

I'm also unsure of where the needle was set prior to removal, as the c clip popped off when removing the cable. I tweaked to tighten the c clip, and set at #2 from the top.#3thru #5 seems to be worn a bit.

I guess if someone can answer the slide operation, I can see if it might be slide or slide spring damage.

I will be going to work on the bike today, and bringing it back home tonight for front end replacement.Lonestar a arms, 03 hydraulics,450r shocks.....Gonna suck if I cant get it running, or blew a hole in the piston..............=(.

 

[stallion81]

Kinda got it figured out =). Gonna get a new cable and possibly a slide spring, jet "kit" also if there is such a thing(but its probably the cable)....... Where to get the cable? Any links????? Thanks.

 

[98blaster+4]

get your cable from motion pro directly, they have ridiculously fast shipping and have anything you need.

 

[stallion81]

Well got that bike running finally. New cable.

Prior cable(3-4" longer) was routed thru the bars and strapped to the left side upper frame, back into the carb.

Routed new cable the same, no go.... I got Clymers, so found the real manual online, very vague. Found a post. Cable thru cable oval, back up over frame, just under center gas tank, to the carb. Walla. The pilot at 48 is too big, but its running fairly good at around 3/4-1 turn out on airmix screw. Haven't actually been on some real turf, to roll with it......BUT it runs again.

A cable causes tons of problems with a carb, new to me, but so be it.Would have never changed a thing if the carb wasn't leaking like a sieve.....