OKO Carburetor Kits on Bultacos
This page is to provide you with information and photos of the OKO K 100 series kits we have available for Bultacos. The bikes pictured below all have been fitted with OKOs. We have used these bikes and others to determine the best size and jetting for various models and engine sizes. We are developing this page so you can order the right bultaco kit along with kit options. We hope this makes choosing a kit a little easier
All of the 250 Bultacos we have fitted with the OKO, including a Model 49, not shown, have used the 26mm K-101. The above photos are of two Alpinas that were originally fitted with Spanish AMAL s, 27mm in size. These were both flange mounted so they used the "Fange Mount" kit. Besides smoother running, the most evident improvement over the AMAL has been low to mid-range power and much quicker acceleration.
After testing and evaluating OKO carburetors on my own and others' 244cc and 326cc Sherpa Ts in the Mid-Atlantic Vintage Trials series for about three years, we are now fitting most of them with the 26mm K-101. Some run well with the 28mm, but almost all of them perform their best with the 26mm. It eliminates the flat spot sometimes found just off of idle when using the 28mm. For the 350cc Alpinas we have fitted 26mm carburetors though 30mm with very good results. The 26mm gives the best overall performance, as it does on the Sherpa T, but riders who believe "bigger is better" may want to use the 30mm which does give more top end for those who ride with a lot of throttle. You can decide below what size carburetor you want, as well as whether it is for a flange or spigot mount manifold. If you choose a larger size, and find you have a lean spot at the cutaway (1/8th throttle), we will gladly swap you for the smaller size. We have full confidence you will immediately notice more power and better response with the OKO and like them as much as we do.
Flange Mount for Amal Concentric Replacement: Bultaco
Remove manifold studs. Photos shows the rubber adapter with a rubber insulating block; attach with 8mm x 25mm allen screws.
Insert spigot end into adapter , adjust for vertical (match lines top of adapter and carb), tighten clamp and viola!
Click On Small Photos For Larger Ones
Flange Mount Kit with jetted carb, extra main jet, flange adapter with hose clamp and mounting bolts.
OKO K-101 Carburetor Kit
This kit is for replacing either the flange mounted AMAL Concentric carburetors, or the spigot mounted AMAL MKII or Bing carburetors on 250cc through 350cc Sherpa Ts and Alpinas. Choose the right carburetor from the list below.
Optional clear float bowl
OKO K-101 Clear Foat Bowl
OKO offers this clear float bowl for the K-101 series so you can easily check the float level, or see if any dirt or water has accumulated in the bowl. It attaches with four screws (incuded). It does not have the bottom nut for access to the main jet. This may be purchased by itself or with a K-101 Carburetor kit. Click on the "options" below.
Note: We are curently working on Bultaco Frontera and Pursang carburetors and kits. Contact us if interested in these larger carburetors for your "go fast" bike.
Above: Bore of 30mm is taller that it is wide, giving the same low end power as the 28mm, but with more top end