KX Riders

Maintenance & Technical => KX100 / KX85 / KX80 / KX65 / KX60 => Topic started by: GREENKAW24 on April 07, 2013, 11:48:48 AM

Title: KX119 Supermini Hillclimber
Post by: GREENKAW24 on April 07, 2013, 11:48:48 AM
(http://i94.photobucket.com/albums/l81/GREENKAW24/superminihilllclimber4-7-2013.jpg)

Bike we built last season for the 125cc Class. Will be 2nd full season for this bike ridden again by Jason Larivee Jr. (5th place overall in 2012)
54.5mm bore x 51mm stroke
Title: Re: KX119 Supermini Hillclimber
Post by: sandblaster on April 07, 2013, 01:53:45 PM
Nice!
Care to share some details?  :-D
Nothing that is super top secret....  :wink:
Title: Re: KX119 Supermini Hillclimber
Post by: riproost on April 07, 2013, 02:57:36 PM
Cool...Looks like all business!
got any video of the 125 class?
Title: Re: KX119 Supermini Hillclimber
Post by: Motorrad on April 07, 2013, 02:59:31 PM
Quote from: riproost on April 07, 2013, 02:57:36 PM
Cool...Looks like all business!
got any video of the 125 class?


I still watch your video fo the 200cc class Bultaco all the time ..         thinking I need to modify my campera...........
Title: Re: KX119 Supermini Hillclimber
Post by: motopunk on April 07, 2013, 07:11:11 PM
Quote from: GREENKAW24 on April 07, 2013, 11:48:48 AM
(http://i94.photobucket.com/albums/l81/GREENKAW24/superminihilllclimber4-7-2013.jpg)

Bike we built last season for the 125cc Class. Will be 2nd full season for this bike ridden again by Jason Larivee Jr. (5th place overall in 2012)
54.5mm bore x 51mm stroke

nice bike... if it runs like the amazing look, it will be a little monster...  :-D
Title: Re: KX119 Supermini Hillclimber
Post by: GREENKAW24 on April 07, 2013, 11:18:54 PM
Quote from: sandblaster on April 07, 2013, 01:53:45 PM
Nice!
Care to share some details?  :-D
Nothing that is super top secret....  :wink:

Started as 2004 KX85, has a 17 inch rear wheel, 19 inch front wheel, 33mm Keihin carb, 5mm stroker crank, VHM Head, VHM reed valve, Hybrid KX85/KX125 custom exhaust.
5mm is the absolute most you can stroke this motor. The transfer timing gets too high, even when cutting the stroke clearance into the head instead of raising the cylinder. Not enough blowdown.
Most people stop at 112cc when making this motor a Supermini, we figured we could squeeze a few more cc's out of it.
It competes against all the standard sized 125cc MX bikes.
The pros of his bike are that the HP is so close to the 125's, and it is 40-50 lbs lighter.
The cons are the suspension travel, and the wheel diameters.
Last season was spent dialing in the gearing/jetting/suspension, and the young rider getting used to the bike.
I don't have videos, as I'm either riding or wrenching all the time, so I don't record any myself.
There must be some out there though.
Its definitely an impressive little bike.