KLX 140 mods

Just a little info for anyone interested - still a work in progress.

Bought the bike for my better half couple of months ago - she loves it electric start,low seat height,light weight.

Still tracking down KX front end not too many of these available in NZ.

Put FMF power core muffler on - lost alot of weight and gained alot of noise!!

Ended up pulling muffler apart and welded 30mm washer over end of baffle then drilled 7x5mm holes in it,in an attempt to reduce velocity.

Still quite loud but lost the nasty rasp which could be heard for miles!!!

Really needs bigger header pipe as the FMF is only muffler and mid pipe which are 25mm while the stock header is only 20mm - sure I would gain a bit of top end with the bigger header pipe.

As for the carb what a bloody nightmare:banghead:

Jets are non existent for the PB20 Keihin in NZ,I know KLX110 jets fit but I had trouble getting anything larger than 95mj and could not find a bigger pilot anywhere.

So after a lot of phone calls and internet searches couldn't be bothered with it anymore so I bought a 22mm mikuni off ebay which only required slight modification to the bolt on inlet spigot from the keihin carb.

Used the stock throttle cable in fact screwed the keihin carb top straight onto the mikuni carb too easy.

Carb came with 95mj & 15 pilot - didn't have any other jets at the time (weekend)so just went with what was in there.

Bugger me first push of the button and it fired and idled better than it ever has - wee bit of tweaking on the mixture screw and it runs beautifully.

Have since put 105mj in and left pilot alone - mixture screw 2 turns out runs great.

Have also opened up airbox on cover -25mm x 50mm hole.

All of this has given the bike much better starting,smoother idle,quite a large increase in bottom and midrange power and a small increase up top - although I'm pretty sure a larger header pipe may help up top as well.

Bike will now lift front wheel with no clutch in first and second with a small tug on the bars.

Thanks must go to ART5 for ideas and info - love the KX forks.:thumbsup:

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