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Should I try to jet my mikuni carb

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The best way to jet it is to put it into the round file (garbage can) and let the proper people dispose of it.

 

I switched to the PWK and would never own a 250 with a Mikuni.. That's just me.   Shrub it up has apparently had some success getting the TMX to work *well*. I have never ridden his bike so I can't confirm that statement. PM him and he will probably respond and help you with jetting the TMX if you keep it.

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The best way to jet it is to put it into the round file (garbage can) and let the proper people dispose of it.

I switched to the PWK and would never own a 250 with a Mikuni.. That's just me. Shrub it up has apparently had some success getting the TMX to work *well*. I have never ridden his bike so I can't confirm that statement. PM him and he will probably respond and help you with jetting the TMX if you keep it.

exactly how I feel about the tmx one day it's fine next it's loading up like crazy and fouling plugs left and right. Thanks ill probably see what shrub has to say about it

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I fooled with those Mikuni carbs for far longer than I should have. It's not difficult to get them jetted so that the bikes runs perfectly. The problem is keeping them that way. My recommendation is to pitch the TMX and buy an Airstriker.

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They are extremely temperamental. I have a 02 with a 32.5 PJ 370 MJ, stock needle in first clip, 1.5 turns A.S, 32:1, S9 Nozzle, 05+ cylinder base gasket, stock reeds. Runs pretty good but doesn't like to restart when hot occasionally  It's always something. I tried a PWK brand new from a 2000 CR250 and it didn't run noticeably "better" even after jetting lean or rich. Had I of kept that for a while I could have commented whether it was more stable. Everybody else reports on the PWK stability so it must be. However, the other reports indicate a PWK will chase down 450s in a drag race so some of the results may be exaggerated some. :busted:

 

I have ridden a 07 with motor work and the PWK. Definitely runs better!

Edited by shrubitup

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I fooled with those Mikuni carbs for far longer than I should have. It's not difficult to get them jetted so that the bikes runs perfectly. The problem is keeping them that way. My recommendation is to pitch the TMX and buy an Airstriker.

yeah I'm not gonna waste time on it ill buy an air striker thanks

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They are extremely temperamental. I have a 02 with a 32.5 PJ 370 MJ, stock needle in first clip, 1.5 turns A.S, 32:1, S9 Nozzle, 05+ cylinder base gasket, stock reeds. Runs pretty good but doesn't like to restart when hot occasionally It's always something. I tried a PWK brand new from a 2000 CR250 and it didn't run noticeably "better" even after jetting lean or rich. Had I of kept that for a while I could have commented whether it was more stable. Everybody else reports on the PWK stability so it must be. However, the other reports indicate a PWK will chase down 450s in a drag race so some of the results may be exaggerated some. :busted:

I have ridden a 07 with motor work and the PWK. Definitely runs better!

What elavation are you at?

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Those are my summer settings so 2500-6500 feet elevation. Winter settings soon to richen back up for 0-1600 elevation.

im at 400-500 feet I might try to jet the mikuni once. What do you recommend I start at? The temps right now are 15-20 C but in the summer 20-30C

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im at 400-500 feet I might try to jet the mikuni once. What do you recommend I start at? The temps right now are 15-20 C but in the summer 20-30C

 I've only used the Honda jetting chart in the manual. Mine is different than yours since 01-03 used flat side TMX. If you have a manual just follow their suggested settings. You can typically vary one up/down from the chart. 

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I've only used the Honda jetting chart in the manual. Mine is different than yours since 01-03 used flat side TMX. If you have a manual just follow their suggested settings. You can typically vary one up/down from the chart.

ok thanks for the reply!

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ok thanks for the reply!

 

If you jet it go with pro-circuit's jetting recommendations. Should get you close. May need to adjust for temp a little.

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If you jet it go with pro-circuit's jetting recommendations. Should get you close. May need to adjust for temp a little.

yeah temps are all over the place right now thanks

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If you jet it go with pro-circuit's jetting recommendations. Should get you close. May need to adjust for temp a little.

 

Those are optimized for sea level at 70F but do work as a baseline to adjust from. Sort of what Keith said. :bonk:

Edited by shrubitup

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Those are optimized for sea level at 70F but do work as a baseline to adjust from. Sort of what Keith said. :bonk:

Ok the temps are getting pretty cold now thanks

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ON  my '05, I found my stock TMX w/ the TPS to be less temperamental than some here are saying theirs were.

 

But to control the spooge, I bought two leaner TMX needles from Honda, and that proved to be better at keeping consistent jetting and reducing the spooge than the stock

Edited by minibikedad

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ON  my '05, I found my stock TMX w/ the TPS to be less temperamental than some here are saying theirs were.

 

But to control the spooge, I bought two leaner TMX needles from Honda, and that proved to be better at keeping consistent jetting and reducing the spooge than the stock

Where did you get the needles and what were they? Thanks.

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05-07 CR250R

 

35 pilot

stock needle in the #2 position

430 main jet

 

rich on the bottom, lean everywhere else.

 

the mikuni isn't horrible, runs good, i know it would run " better " with the keihin, but it runs really good as is.

 

someone said that little screen in the back of the mikuni might be &%$#@!ing things up a little and i have heard around the net to remove it.

Edited by Atieri

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Mine isnt all that bad. sure it will have its days, but its pretty consistant and running well.

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what size pilot and main do you use ?

 

Mine isnt all that bad. sure it will have its days, but its pretty consistant and running well.

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