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252
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1/15/2011
Location
Hays, KS
US
I am starting a big build on a 2003 kx125 and throwing around the idea of the Lectron because I have seen multiple KX builds using it. I'm not opposed to spending the money on it but I also am a very "don't spend the money if it's not worth it" type of person.
Just wanted to get some feedback and advice. I will probably just send the cylinder off for porting but may end up punching it out to a 144 so I don't know if that makes a difference.
I pretty much only ride MX if that matters as well.
Any feedback/advice is greatly appreciated.
Just wanted to get some feedback and advice. I will probably just send the cylinder off for porting but may end up punching it out to a 144 so I don't know if that makes a difference.
I pretty much only ride MX if that matters as well.
Any feedback/advice is greatly appreciated.
I’ve also had a YZ250 and CR125 with the Keihin airstriker carb and I was just as impressed with that as I was the Lectron...maybe even more impressed with the Keihin due to it being a lot cheaper.
I think if you know what you’re doing with jetting then the Keihin can be just as good as the Lectron, without a doubt.
Obviously the Lectron has the convenience of not having to worry about jetting, but for the extra money it costs...I’d rather just stick with the Keihin
A ‘97, ‘98 KX250 has the Keihin carb you’re after and will work with your KX125 just fine, obviously you’ll have to adjust the jetting as it’ll be jetted for a 250.
A popular mod for the ‘03 KX125 was to swap the intake and air boot setup for the ‘04-‘05 intake and airboot setup, it was a huge improvement and gave the bike a lot more power...with the correctly jetted carb and new intake and boot setup I think you could expect a 4-5hp gain
The Shop
Prior to this, i had the stock mikuni tuned about as well as i could possibly get it.
With the Mikuni, i couldn't get the bike to idle consistently. With the lectron, it idles like an EFI bike almost. Huge improvement there.
The Mikuni screamed and offered great overrev qualities when tuned perfectly. The lectron seems to give some up in this area.... its a little flatter in the super high revs and overrevving.
Everywhere else, the lectron provides more consistent and smooth power. I think the Mikuni hit harder and pulled higher in the rev range, where the lectron smooths out the hit, almost like the power slightly shifted lower in the rpm range.
Maybe with some more tuning of the powerjet on the Lectron, i could get it close to the high rev performance of the Mikuni. We'll see.
Post a reply to: Carb choice for 2003 KX125. OEM? Lectron? Keihin?