Change of plans mikuni-keihin issues

Budget_Blaster

New Member
Dec 25, 2009
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Ok i just spent many hours trying to mount this TM34 and im convinced with a stock boot it just aint possible due to its size and shape.Ive tried about everything imagineable and have two problems one the carb doesnt seat all the way into the boot due to interference with the lower left bolt ive tried all types of different bolts with an assortment of different heads none worked and the second is even with a spacer it just hits the clutch lever.Soooooo i give up.

I got to looking at this KEIHIN PWK 35 i have on my KDX200 and its perfect in every way fitment is like yamaha intended it to be used on the blaster even with a dremeled boot.So i swapped the TM34 to the kdx and sure as sh*t it fits like a glove.

Now im planning to use the Keihin on my blaster and the mikuni on the kdx anyone see any issues with this?

The keihin has a 158/45 with a DGL needle but i also have a CEL and BGP needles that i can swap into it.Will the jets in the keihin be enough for my blaster?The KDX loved this combo but will the blaster.

The mikuni has a 330/45 and 6FP63 jet needle will this be enough for my kdx?

Im really at a dead end here since im mixing and matching here so any of you guys familiar with these carbs or that are just good at tuning please chime in.
 
that jetting should be fine for your bbk, because its cold out i am running160/50 but could easily go down to 155 48 and still be safe
 
Thats great news!!!!

How much better/worse is this carb?

Any ideas on running the mikuni on the kdx?The kdx isnt too wild just boysens,fmf desert pipe,and a uni.
 
i'm with noobs on the keihin
in my 34pj, ported stock cylinder/all the goodies
i run a 45/155/dgh needle in summer, 45/162 in cooler months, and stay on the couch during the "below freezing" winter
no clue on the kdx
 
Ok i just spent many hours trying to mount this TM34 and im convinced with a stock boot it just aint possible due to its size and shape.Ive tried about everything imagineable and have two problems one the carb doesnt seat all the way into the boot due to interference with the lower left bolt ive tried all types of different bolts with an assortment of different heads none worked and the second is even with a spacer it just hits the clutch lever.Soooooo i give up.

I got to looking at this KEIHIN PWK 35 i have on my KDX200 and its perfect in every way fitment is like yamaha intended it to be used on the blaster even with a dremeled boot.So i swapped the TM34 to the kdx and sure as sh*t it fits like a glove.

Now im planning to use the Keihin on my blaster and the mikuni on the kdx anyone see any issues with this?

The keihin has a 158/45 with a DGL needle but i also have a CEL and BGP needles that i can swap into it.Will the jets in the keihin be enough for my blaster?The KDX loved this combo but will the blaster.

The mikuni has a 330/45 and 6FP63 jet needle will this be enough for my kdx?

Im really at a dead end here since im mixing and matching here so any of you guys familiar with these carbs or that are just good at tuning please chime in.


MOST people buy a replacement boot when they try to run a larger carb. I know for a fact that the UPP boot is about 3/8" longer than the stock boot. I'm sure that it would allow you to clamp that carb body on.

That being said, you can run a KDX on a TM34 and you can run a blaster off a PWK33.

Your jetting sounds like it will be close enough (for a starting point anyway) for both machines.
 
i'm with noobs on the keihin
in my 34pj, ported stock cylinder/all the goodies
i run a 45/155/dgh needle in summer, 45/162 in cooler months, and stay on the couch during the "below freezing" winter
no clue on the kdx



So will the 158/45 DGL,CEL,or BGP be ok in 30 degree temps on my blaster?
 
MOST people buy a replacement boot when they try to run a larger carb. I know for a fact that the UPP boot is about 3/8" longer than the stock boot. I'm sure that it would allow you to clamp that carb body on.

That being said, you can run a KDX on a TM34 and you can run a blaster off a PWK33.

Your jetting sounds like it will be close enough (for a starting point anyway) for both machines.

Its a pwk 35 if that matters and yea thats what im going to do id rather not have to buy another boot at this point so im going to mix and match.

By the way bro i disassembled that carb in those are some funky ass floats lol and there was what appeared to be aluminum powder in the float bowl so i soaked it a few hours in seafoam and then blew all the passages out with carb cleaner and compressed air other than that i cant wait to see this on my kdx in action.
 
Well we shall see then thanks guys.

And any of you with kdx200's let me know on the jetting for the mikuni setup on my kdx i love that bike and dont see 1 mm being all that much of a downsize but ive been wrong before...like once lmfao
 
Personally I'd start 1 or 2 sizes bigger on that main on a ported BBK in cooler temps, the airscrew position it idles the highest at will determine what that pilot circut wants
 
Its a pwk 35 if that matters and yea thats what im going to do id rather not have to buy another boot at this point so im going to mix and match.

By the way bro i disassembled that carb in those are some funky ass floats lol and there was what appeared to be aluminum powder in the float bowl so i soaked it a few hours in seafoam and then blew all the passages out with carb cleaner and compressed air other than that i cant wait to see this on my kdx in action.

Those are some funky ass floats LOL. Seem like they'd work pretty well though, even off angle when a "pivot" type float might hang...

Aluminum powder? Must have floated down in there during "other operations" in the garage. Strange though, it was setting in a box together in the corner of the garage.

The two carbs should work equally well on either engine. Your jetting sounds CLOSE but if you have it, you can follow Awk's advice and bump up the main from the 158 to 160-162 range just to get a little more fuel to it for testing purposes. I have a feeling you're going to end up in the 155-158 range before it's over with but you can't be sure without a plug chop!
 
cool so whats the best way to mod the stock air box i followed the link awk posted and most said the guy did it wrong.Anyone got a laundry list of exact parts and sizes to buy to fit this pwk 35 to a stock air box and pics of the CORRECT way to go about this?
 
i believe yz otis posted that link/pics where someone used about a 6" piece of pvc, cut the airbox boot back a little at a time till the pvc fits in tight, clamp it on, for the pvc to carb...measure the outside diameter of the rear of carb, in inches, then go to any good hardware store and ask for a "fernco" fitting to go from 2" pvc to the measurement on the carb
 
i believe yz otis posted that link/pics where someone used about a 6" piece of pvc, cut the airbox boot back a little at a time till the pvc fits in tight, clamp it on, for the pvc to carb...measure the outside diameter of the rear of carb, in inches, then go to any good hardware store and ask for a "fernco" fitting to go from 2" pvc to the measurement on the carb

So the 2x2 peice wont work in the link you posted?

What about the coupler is there a particular one or brand i should get that will hold up to fuel?
 
a lot of guys are running a "fernco" plumbing coupling/reducer on the back of their carbs, found at any hardware/plumbing/home stores, they come in a bunch of different combinations of reducing sizes, the 1 3/4" prolly needed for the back of your carb probably isn't one of them. as thats not a common plumbing size ???
i'd think 1 1/2" pvc has an o.d. of 1 3/4 ???
or is pvc already rated at o.d. ???

if your not finding anything in a ferco fitting suitable,
heres what a I and few others of us run, and swear by, they come in every conceivable size needed.................

Intake Pipe Reducer

i believe mine is a 2.25" x 1.75", but that 2.25" is for my cfm airbox tube, you'll need to measure for your exact need
ps.....get the clamps from there too, they are (.)(.)'s
 
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