"I just wanted to share this amazing project with all of the two stroke fans out there. We just finished this factory level 2 stroke build after a year and a half of R&D, testing, changes, etc. The end result is amazing and we ended up with a 53hp rocketship that weighs 15 lbs less than the AMA minimum weight limit for that class! 201 lbs, ready to ride with an empty tank. We used a Varner Motorsports modified KTM 250 sx powerplant in a 2011 Honda 450 frame with production based Showa suspension including a SFF Showa fork, modified, valved and set up by MB1 Suspension. The entire engine cradle and billet engine mounts are hand fabricated and machined to accommodate the KTM powerplant. Racetech Titanium was instrumental in helping bring the weight down with all of their titanium fasteners, axles, brake piston and pivot hardware. The bike also utilizes many one-off titanium or alloy parts and heavily modified OEM parts as well. DLC coatings were utilized in many critical areas including the shock shaft, brake hardware and pins, brake pistons, select transmission parts, titanium linkage pivot bushings, and swingarm pivot bolt to name a few. It took over 500 hours of trial and error, testing, changes, extensive mods and many hours of scratching our heads to get it perfect but I feel this is the most refined 2 stroke conversion build anyone has ever done. "
"My vision was to create what I thought would be a factory level two stroke offering if they fielded one today, so I agree with you 100% "
"The first to create an aluminum airboot as far as I know but I'm not sure. It was the only way we could get the intake to line up correctly without compromising intake boot volume and also clear the shock, chain roller, etc. I didn't want it to be hacked together like most conversion bikes I've seen. It was more of a solution to a problem than anything else but it turned out sick for sure. Saved about 1/2 pound over the stock setup too. "
"You would be surprised how it stacks up against 450's. It is incredibly fast and not as hard to ride as you might think. KTM did an amazing job when they designed the latest generation 250 two stroke and they make a lot of useable, linear HP. It will pull most of the 450's on the track on fast 4 gear + uphills. Varner did an amazing job with the porting and head work and we use a JD full race ignition as well. It has hurt more than one four stroke riders feelings out there I can assure you. "
"I agree the thumpers have made huge advancements in recent years but its not just about HP either. The same rider can carry far more corner speed on a 2 stroke vs 4 stroke because of the lower weight and lack of gyro and therefore eliminate the need for so much power. I think this is one of the reasons we are seeing faster lap times at many of the nationals and SX races from the lites class. They just handle much better and they don't feel like such a pig because of the higher RPM's and the lighter crank, less inertia, etc. Just a thought, no way to validate that however.... "
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keeptwostrokesalive wrote: Im curious. Considering the 2013 sx250 is the lightest production 250 two stroke out on the market right now, why did you guys choose the aluminum frame? Was it just your personal preference or was the aluminum frame actually lighter than the KTMs steel frame?
Crush wrote: Yeah I kinda thought the same thing... not that i'm criticising it, it's fuckin amazing, but I did kinda think why not just goto town on a 250SX... kinda like what FMF did with the CrazyLite300
The KTM would be about 5 lbs heavier, maybe more. The linkage equipped KTM weighs 217 lbs, that Dirybike mag project you are referring to was the chassis without linkage. "
53hp, 201 lbs"
AJ wrote:
You think your art piece will find it's way to racing (I assume amateurs since I don't see 400 of these being produce any time soon)?
Well agreed, on most any of theses type bikes being homologated for Pro racing in MX/SX..
Its possible but a tough deal and I've been through the AMA homologation process on our Service Hondas.
That said :
if you really think Suzuki met the 400 unit numbers,in the USA warehouses ready for inspection , by the October deadline of 2010 / 2011 or 2012 on their 450's or 250's four strokes, i've some Ocean front property in Warsaw to sell you.
but no one really wants to talk about such things..
How cool would it be to see Roger Decoster put K-Roc on a 250sx for the SX series? That would shake things up a bit. I think his riding style is well suited to a 2 stroke. He did really well in that GP a few years ago (the moto he didn't crash) when he raced the 125 at the last round because KTM had already clinched the title. Cairoli was supposed to race the 250 too but his mom died the Friday before the race and he skipped the last round instead. "
this was posted on vital, but i'll save yall from the foul nature of that site, by copying/pasting everything that is in the thread over there
my sacrifice to you(fellow tsm'ers)
