USA-OKO, Who We Are
As president of Mid-Atlantic Trials from 2000 to 2020, one of my goals had been to keep older trials bikes running their best to keep them in competition.  One of the major problems with the older bikes is the older, lower tech carburetors fitted to them, many that are simply worn out or spare parts prices are ridiculous.  After working on AMAL, Mikuni, DeLorto and Bing carburetors for years, and often being frustrated by the lack of available parts, or by an inability to get the best out of the engine using these carburetors, in 2011 I came upon the OKO K-101 series.  These carburetors have been used in Australia and Europe for several years with supposed improved performance, so I decided to try one on my 1978 Bultaco Sherpa T Model 199, which has a 326cc engine with a Bing 28mm carburetor.  I was not displeased with the Bing as it seemed to be dialed in nicely throughout the whole throttle range.  However, I was extremely impressed with the improved throttle response and power provided by the OKO over the Bing.  The Sherpa T has a large gearing gap between 3rd and 4th gear, and I would often be switching back and forth on the loop between these two gears; 3rd would be too low and I'd be revving the engine quite a bit, but 4th would be too high and lack power to pull hills.  With the OKO I can go to 4th gear and leave it there, with plenty of power on practically any incline.  This is where I initially noticed the increase in power.  Beyond that, throttle response was immediate, providing that extra power across the throttle range instantly.  I purchased more OKOs for my other Sherpa Ts and my 500cc AJS/Matchless trials bike, and the results were the same.  At this point I decided to see if I could market these to other trials riders.  After unwittingly purchasing a few Chinese copies (which I could not get dialed in) I was able to contact the factory in Taiwan directly and buy directly from them.  Since that time I have fitted the OKO K-101 series carburetors to many different brands and models of motorcycles with excellent results across the board.  These carburetors are of excellent quality, relatively easy to dial in, and though they have their differences from the round slide carburetors they usually replace, they are similar enough when it comes to tuning that the average guy who knows basic tuning of other carbs has no problem dialing them in.  So as this is being "written" we are primarily providing the OKO to trials riders for their bikes, but these carburetors are suited to other competition and road bikes as well.  We have fitted  250cc Can Am cross country bikes with OKOs (32mm in this case), as well as  Bultaco Fronteras with a 32mm and 34mm carbs, and a 370cc Bultaco Pursang with a 38mm.  I have also fitted a 28mm OKO K-101 to a single carb. 650cc BSA with impressive results.  Since then, we have put these on many pit bikes, bicycle engines and a plethera of other motorcycles.  As we fit the OKO to more bikes we will offer kits for those bikes.  If you happen to live nearby, and can leave your with us bike for a few days, we will put an OKO on it and dial it in for you at no extra charge.  You pay only for the carburetor.

I am committed to keeping our older bikes on the road and in competition.   To that end, the OKO K-101 series of carburetors has been a boon to eliminating one of the problems that plague older, as well as newer bikes, lack of good carburetion.

Roger Annable
Mid-Atlantic Trials