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Post Info TOPIC: 32mm carb


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32mm carb
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had enough of the TTR carb leaking fuel...

Time to put the 32mm flat slide on...

the carb is 12mm shorter the the TTR carb so will

make a 12mm thick block to go between the head & manifold

that will move the carb/manifold back 12mm to get the inlet

into the air boot...

put a 42 pilot & 50 main jet in it to give a start point....



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Bikes... 06 TTR250 / 09 XT660R / 1977 Montesa Cota 348 MRR / 1979 Montesa H6 125 Enduro...

O yer and a Quad...



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Interesting. What brand is the carb ? How does it run with those jets ?

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2004 TTR250. White Brothers E series exhaust, modded airbox, rejetted, 13/48 c&s & many more mods..



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 KOSO.. ====> http://www.koso.com.tw/products.php?id=29&lang=en
JETS.... as I said it's a start point
it either won't run or will run like crap,..



-- Edited by petenz on Tuesday 29th of March 2016 04:26:17 AM



-- Edited by petenz on Tuesday 29th of March 2016 04:28:07 AM

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 http://www.kiwibiker.co.nz

Bikes... 06 TTR250 / 09 XT660R / 1977 Montesa Cota 348 MRR / 1979 Montesa H6 125 Enduro...

O yer and a Quad...



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not anything to do with the carb replacement....
a nice pretty set of blue braided brake lines turned
up in my mail box 2 day...




..

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 http://www.kiwibiker.co.nz

Bikes... 06 TTR250 / 09 XT660R / 1977 Montesa Cota 348 MRR / 1979 Montesa H6 125 Enduro...

O yer and a Quad...



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In my first post I said I put a #50 main jet in,,,, should have been #150..

now running 45 pilot & 152.5 main....
runs great apart from a slight stammer just off idle
if you snap the throttle open...
plug shows its maybe slightly lean at the top...
it starts very easy on a cold motor... thats tells me it
maybe also a tad rich on the pilot jet...

So will go back to the 42 pilot & try a 155 main next..
then fiddle with the needle setting.. see how it goes...
Also it's so easy to change jets... losen the clamps turn the carb
onto a 45* angle un-screw the fuel bowl.... easy easy easy..

how dose it go...
right from when I put it on the first thing I noticed
was the exhaust note was deeper... "GYTR pipe"
It's a lot faster on the throttle & can be a bit
snatchy on & off the throttle "compared to what the TTR
is standard but no worse than a lot of bikes I have
riden/owned..
Power from about mid range seems stronger " seat of the pants dyno"



....


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.....................................................................................................

 http://www.kiwibiker.co.nz

Bikes... 06 TTR250 / 09 XT660R / 1977 Montesa Cota 348 MRR / 1979 Montesa H6 125 Enduro...

O yer and a Quad...



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Had to find more information on this!  How is it running now, looks like this was done a while back from the post date.  did you get the jetting dialed in?  is it still stammering off idle?  maybe due to no accelerator pump?  Its funny because i run a Lectron Carb on my YZ250X and love that thing, zero issues with temp or elevation changes and fires first kick every time cold or hot also improved fuel economy and since installation I have yet to foul a plug (pretty difficult to accomplish that on a 2 stroke without rejetting for various elevations and temp changes).

the Lectron is a Power Jet carb, the adjustment behind slide on top which is for WOT only, wondering if this carb your running is the same?

 

please more information you have a very interested party here!!

 

Thanks!

 

Chris



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petenz wrote:

how dose it go...
right from when I put it on the first thing I noticed
was the exhaust note was deeper... "GYTR pipe"
It's a lot faster on the throttle & can be a bit
snatchy on & off the throttle "compared to what the TTR
is standard but no worse than a lot of bikes I have
riden/owned..
Power from about mid range seems stronger " seat of the pants dyno"



....


 

if the snatchyness is due to a different blade opening speed, you could always tone it down with a G2 adjustable cam throttle tube, I also run one of those on my YZ250X and found it very useful for managing tricky obstacles with more finesse. maybe the stock carb actuation is cammed with the funky linkages it uses?

 

Chris



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petenz wrote:

In my first post I said I put a #50 main jet in,,,, should have been #150..

now running 45 pilot & 152.5 main....
runs great apart from a slight stammer just off idle
if you snap the throttle open...
plug shows its maybe slightly lean at the top...
it starts very easy on a cold motor... thats tells me it
maybe also a tad rich on the pilot jet...

So will go back to the 42 pilot & try a 155 main next..
then fiddle with the needle setting.. see how it goes...
Also it's so easy to change jets... losen the clamps turn the carb
onto a 45* angle un-screw the fuel bowl.... easy easy easy..

how dose it go...
right from when I put it on the first thing I noticed
was the exhaust note was deeper... "GYTR pipe"
It's a lot faster on the throttle & can be a bit
snatchy on & off the throttle "compared to what the TTR
is standard but no worse than a lot of bikes I have
riden/owned..
Power from about mid range seems stronger " seat of the pants dyno"



....


Did you ever settle on a good jetting combination that worked over whole rev range?  I have the carb on order and they are going to send me extra jets and needles.  Found a seller local (in the US at least), hoping to have it in hand by Thursday!! Pretty excited, all kinds of fueling issue with the stock carb and just ready to be rid of it for something simpler!!



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I have had luck getting rid of that small lag at throttle snap by adjusting the valves. Also do you have a picture that shows how the throttle cables attach?



-- Edited by bwaldo on Monday 19th of June 2017 05:05:01 PM

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Veteran Member

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the stock carb already has everything u need i wouldnt change it its a good carb u can inject it and everything and the acell. pump if its increased u can make the squirtevileyeyawn come on faster

and you can bore the stock carb and roughed and polished the intake and exaust and the tourqe curve comes on faster and the us header helps alot for acel and tourqe the short header kills it and the stock pipe de baffled and cut the spark arrester off and stick the stock cap back on and it makes more power than the fmf or yoshi thats just weight diffrence to mehmmhmm

 



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