Hi All,
thanks for your replies. -- @epinut: thats exactly the information I was looking for ...
The DC-11 carburetor was mounted on my 59XLH, wenn I bought it back in the 90s -- I have tried to use it on the XLH, but without success. Especially idling and the acceleration from idle speed on was causing problems. After mounting a DC-6 I aquired, I was pretty happy with the DC on my XLH. Although I still think the CV carb was the best option so far.
Anyway: The DC-11 was a lucky coincidence, as it would fit (more or less) perfect to my XLCH build. The Dr. might remember this, although ist been a loooong time since I started. It is a full ball bearing engine with a 59XLCH engine number in a XLRTT frame. Inside are KHR flywheels and big rods (the 55R type) with aluminum cylinders with (now) 3,3" bore. The Dr. helped me a lot in designing the pistons, which I had custom made by "Wahl" -- The engine has 77cui, so a bored out DC might work or might be to small -- I will find out.
I would have gone for a new-used throttle body, but as I live in Germany, its hard to get them in a decent shape or it takes a few weeks -- yeah, that doesn´t matter, if it took 6 yeards already, but I am close to the finish line.
First I fabricated a small plate that fits into the body and has the 4 wholes already pre-drilled.
- IMG_20211002_235522_792_small.jpg (322.61 KiB) Viewed 34737 times
After that I positioned the plate and fixed it with an aluminium plug from the top side. To make sure, that no brazing material closes the holes again, I plugged them with toothpick tips ...
- IMG_20211003_002612_259_small.jpg (317.8 KiB) Viewed 34737 times
Last but not least, I brazed the plate in place and cleaned the bore out again -- with good results, although the holes have a slight angle (which should´t harm functionality)
- IMG_20211003_125117_821_small.jpg (167.18 KiB) Viewed 34737 times
All holes are now pre-drilled with 0.6mm or 0.0236" -- now a last question:
From reading different sources, I understood, that these ports are a type of idle speed or "throttle-just-opening" valves and that S&S used two or three ports. What would you recommend for the size of the ports (also considering, that this is for a 77cui engine) -- my idea was, that I could use two small und two bigger ports (the bigger ports to the ends and the small ones in the middle)? Any comments?
Cheers, Ralf