carb question

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tommorth
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carb question

Post by tommorth »

i got what i thought was a 35mm pwk off a kdx planing to swap over the 28mm one on my bike at present .Any how I got out the ruler to measure it and the throat on it is 38mm but the outside measurements match those of the 35mm .
Or for some bizzare reason does the 35mm have a 38mm throat ,
or has this been bored out seems like lot

[URL=http://img394.imageshack.us/my.php ... .jpg[/img][/url]
Last edited by tommorth on 02:43 am Aug 10 2008, edited 5 times in total.
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RBD
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Post by RBD »

Hi tommorth,

If the throat measures 38 mm it is most likely a 38 mm carb. The maximum safe over bore on a PWK 33 mm or 35 mm would be 36 mm.

The slide on a 33 and 35 mm PWK carb is about 36.9 mm wide. The slide on a PWK 38 mm carb is about 40.6 mm wide.

The spigot diameter (where it plugs into the reed boot) on the 35 mm carb is 42 mm and the 38 PWK is 46 mm.

As you can see; if it is a 35 mm carb and it is bored to 38 mm, you would see daylight around the sides of the slide. So I would think you have a PWK 38 mm carb.

Check the outside diameter of your spigot and the slide width, it should tell all. I hope this helps :)

Ron
tommorth
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Post by tommorth »

its spigot is 42mm front and 59 rear as per spec foir a 35mm carb
but the throat is definitly 38mm

the slide is about 36mm and apears to be slightly tapered i can see a small amount of light on each side of it

it has a number 6 slide (looks like its had a little bit taken out of one side),160 main ,52 pilot and a 1172 needle
it also has a stupidly stiff spring in it
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canyncarvr
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Post by canyncarvr »

The above link doesn't work at the moment..but I do notice the 'kiwi' part. Might this be a carb off an SR..therefore maybe not exactly the same as US PWKs?

I have no idea..just saying that SRs differ in some odd ways.

If the light you're referring to on either side is indeed the light that Mr. Black refers to that you would get in a small-bodied PWK bored to 38mm with a 36.9mm slide..I would think that what you are looking at is a piece of junk.

:sad:

AAhhh....I just re-read and got the 28mm part. Yup. SR 'fer sure.

.
.
....I think........ :hmm:

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tommorth
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Post by tommorth »

delayed update
yup bike is an sr not that many of them here though most are the same as us models apparantly someone imported a container load of them at some point

My sr has a 28mm carb on it at present thats why i got the 35mm i want more power

I got another carb this one seems in much better cond slide looks new has a150main 45pilot hasnt been played with by a twit
Had a look at them side by side today and the bored one has had some rough things done to it part of the boring involved changing or cuting the jet block so that it is flat in the throat rather than having a raised curved section, also whoever did it was to lazy to go buy the correct srewdriver to remove it and has just cut slots in the screws the stupidest thing is that the air srew was completly shut but not just shut but allmost a third of a turn past closed wtf so yes most probibly a peice of junk but may put it on at some point just to see what its like

usefull discvery for anyone convertin a sr to 35mm carb you need both carb boots and airbox hole in airbox is much bigger unles you want to cut yours but then you cant go back
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