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Fri Dec 30, 2016 12:11 am

I am enjoying this thread. Nice work.

Fri Dec 30, 2016 3:46 pm

[email protected] wrote: I am enjoying this thread. Nice work.
I am glad! Thanks! 8)

Mon Jan 02, 2017 8:05 am

Both carburetors are now mounted, and I am working with the throttle cables
:

It appears the rigidity of the silicon hoses might be enough to support the overhung load of the carburetors. Will see.

Mon Jan 02, 2017 7:17 pm

This thread is cool. I like your thinking outside the box.
If the intake hose needs some support you could just weld up a simple heavy wire "exoskeleton " around it just to give it a little lift.

Tue Jan 03, 2017 12:31 am

finefettle wrote: This thread is cool. I like your thinking outside the box.
If the intake hose needs some support you could just weld up a simple heavy wire "exoskeleton " around it just to give it a little lift.

Thanks. I got onto the idea because dual carb manifolds for the 1200 are not readily or economically available; and because I have seen slide carburetors adapted to aircraft applications of VW aircooled engines.

I might even be able to clamp a 1/2 x 1/16th SS bar along its outside curve. My current thought is to use something like 1/2 x 1/16th SS bar to make a strut, running from the unused bolt on the unused corner of the tin, up and tucked under the carburetor hose clamp.

The cool thing about this arrangement is that I can point the carburetors anywhere in about 150° arc, and can greatly shorten the silicon hose legs if I point them outwards, athwartship. I won't know which position is best until the engine is back on the trike and on the road.

Tue Jan 03, 2017 2:25 pm

I was playing with using two 40mm CV carbs off a Harley Davidson, I have the carbs they are made by keihin, they have a accelerator pump built into them.
I had thought about just using one on a elbow on a stock manifold to see if it would work.

Casey

Tue Jan 03, 2017 5:21 pm

earthquake wrote: I was playing with using two 40mm CV carbs off a Harley Davidson, I have the carbs they are made by keihin, they have a accelerator pump built into them.
I had thought about just using one on a elbow on a stock manifold to see if it would work.

Casey
That would be cool. I was looking at my 1600DP intake castings, and it looks to me like they could be cut just above the head flange, and an inch or two behind the hose coupling. The resulting two ends look like they would be a perfect dimensional match that could easily be welded together such that they would form a vertical manifold that a hose elbow could be clamped to.

Sat Jan 07, 2017 6:07 pm

I have been thinking about how to make up throttle cables for my trike project. Dual slide carbs require motorcycle type throttle cables, and having two carbs means joining the two throttle cables into one cable for the Harley style hand grip. Here is what I have been doing.

This project is complicated by the fact I was hit head-on on Halloween night, suffering a moderate concussion from which I may never fully recover due to my age.

So I need to clip the barrel ends off the two throttle cables running from the carbs, and replace them with 'nipple' ends for use in the cable splitter. For this, I opted to use a solder pot instead of applying direct flame to the cable and risk making them brittle. Not having a solder pot, I improvised:

Crucible:

Plumbing solder:

Two minutes later the solder is melted:

Nipple end on left; barrel end on right; installing a nipple end on the bare cable from the carbs:

1/8" soft brass hobby tubing, cut 3/16" long with 'imp' cutter:

After determining the exact length you need the cable to be, cut it to that length, wash the cable end and cut piece of tubing with a no-residue spray (electrical parts or MAF sensor) cleaner, and slide the cut piece of brass tubing over the end of the cable:

Slide the cut piece back from the end, then, while pinching the end of the cable tightly, about an 1/8" from the end, fray the wires enough that when the cut brass is slid back to the end it will hold itself there. It is probably best to leave a little cable hanging out the end, maybe 1/32". This fraying also gives the solder a better grip on the cable.

After sliding the cut brass piece back in place, dip the cable end into plumber's solder flux, then into the solder pot just enough to entirely cover the cut brass; and hold it there for about 15 seconds. Pull it out and let it cool:

Then clean the new nipple up with a smooth file, being careful not to nick the cable:

Here is the first carb cable nipple, in place, in the cable splitter slide:

Here is the throttle cable splitter, closed up, with one throttle cable installed . . . two to go. I had to disconnect the throttle cable from the carb in order to get enough cable out of the housing to put the cable into the slide.

Before doing any of this, I had installed the cable in the carb, and, while in the closed position, carefully measured how much cable I would need sticking out of the housing on the splitter end, so that the nipple would be seated in the slide while it is in the throttle off position within the splitter. Important. I also closed the cable housing adjuster on the carb end so that I would have plenty housing length adjustment to facilitate balancing the carbs, and so that the slide will not top out in the splitter before full throttle is reached. On the other hand, you do not want to cut the cable too short that when it is all put together it won't relax the carbs to the throttle off position.

Sat Jan 07, 2017 6:45 pm

I am using 5mm cable housings with 1/16"/1.5mm cables for the trike throttles. Many motorcycle applications often use 6mm housings, and the splitter I am using has housing seats sized for 6mm.

5mm housing and 1/16" cable is the same as is used for bicycle brakes; and even for some bicycle shifters. So all this stuff is easy to come by.

I can either let my 5mm housing wallow a little in the larger housing seats, or find some way to shim them to fit. I am going to let them wallow for now, and see how that works. The small carbs I chose are set up for 5mm cable housing. The Harley hand grip on my trike is designed for 6mm housing.

Thu Jan 02, 2025 10:20 am

I assume this project was never finished?