Rotax throttle system mod

[Kyle Communications]

Daniel Leach and myself have been working on a new way to make the throttle system on the Rotax 912 style of engine with the bing carbs a lot better. Everyone knows what a crap system the throttle with the 2 cables is like. The savannah system is terrible and is a issue with all of them the way they do it. Carbs go out of balance regularly and they never track correctly either. We dont claim to be any genius with this but I saw a guy from NZ's post who was a bike engineer and he came up with a similar system but we thought it would be far better with some revision for mounting, twist and control.

I posted the video below on the savannah FB group of the initial prototype and suddenly I got inundated with requests for kits of these. Some 40 at least so far from all over the world and not just savannahs. It can be used on any rotax install of course.

The proto you see in the video is all hand made with bandsaw and file and linisher. Danny has been running it on his sav now for some 15 to 20 hrs and its been faultless.

I drew up all the brackets and bearing blocks also the carb butterfly levers then used those files to generate the models for printing on a 3D printer to confirm everything was correct size and lengths for the movements. I got a initial 8 sets of these all laser cut from 3mm stainless. The bearing blocks I made on my CNC and Danny found the metal tubing for the choke cable so we can thread it so they are long enough to go through the top bracket and screw into the carb body as the original.

So far everything fits exactly as planned I still have to get a few things costed for production like the special SS rolling coupling for the throttle arm to the control rod and the SS keepers for the stainless tube. We have a jig made to get the arms tig welded to the tube so they are at the correct angle as they are not at 90 deg to the tube. Ball links on the major attachments and threaded stainless rod to fit the ball links and also allow carb balance adjustment. 

These pre production ones are going out to locals and also to a couple of other countries for them to install and try and give us some feedback but I am pretty sure there wont be any more mods to the system but thats what the test units are for.

 

 

 

Some pics below to show some of the development