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New Rev 3 Mikuni Carb?


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#91 samo

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Posted 03 June 2009 - 08:08 PM

I'm not good in English..but are we talking about this method: http://www.ntxtrials...ers/RCR0106.pdf (page 2)
This seems to be the easiest method. No drilling...

Samo

#92 samo

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Posted 07 August 2009 - 07:28 AM

I'v done all three mods. Drilling, float tangs mods. and atmosphere tubes mods. and now the problem is solved..;)

I think that you can see on the spark ( black or brown ) if the float level is corect..

#93 si8433176

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Posted 08 May 2011 - 08:24 PM

what exactly gets the treatment from the drill?

would be nice if the above mod works, ill try that for starters but am interested in what you guys are drilling.

Si

#94 Dan Williams

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Posted 09 May 2011 - 12:01 AM

The drill mod isn't necessary. Just set the floats per Billy T's instructions and nipper a hole in the vent tubes halfway up the body and it's fixed. The reason the Mikuni pees fuel out of the vent tubes is the vent tubes on the Beta are too long and end below the float bowl. If fuel gets splashed up into the tubes they can form a siphon and will flow fuel until the supply stops. Nippering a hole above the level of the float bowl kills the siphon. Any fuel that gets up into the vent tube will just go back down into the float bowl or out the end of the vent tube but it won't keep sucking fuel out of the float bowl. It really is that easy to fix.

#95 hrc1

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Posted 09 May 2011 - 09:09 AM

The float tang adjustments do the job, thanks to Billy T.
pdf here

#96 mecajental

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Posted 19 June 2011 - 08:52 PM

Hi.
I would like to show the solution I have addopted to solve the leakage problems. There is no nedd to drill, and the mod is completely reversible.

The little pipe is a brass ballpen refill. Is easyer to weld than stainless steel ones.

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I have modified two carbs, an there is no leackage, even with the bike at extreme positions.

Regards
GasGas Contact TXT 270 1999
Beta Rev3 2005
GasGas Contact JT-25 1994
Mecatecno Dragonfly 50 (Cilindro 74cc, Dell'orto 21)
GasGas Contact T-25





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