Page 1 of 1
B M W R100S with Rotax C box
Posted: Tue Jan 24, 2012 8:14 am
by johnnie wishbone
Is anyone in South Africa flying one of these engines at the moment? I have one I brought from england, I Want to replace the 503 on my CGS Hawk (fixed wing pusher) Ready to install now but have a few questions.
Re: B M W R100S with Rotax C box
Posted: Tue Jan 24, 2012 10:58 am
by smallfly
Aquila used them many moons ago. Power was somewhere between 503 and 508, but some pilots did not like the vibration of the two cylinders.
Re: B M W R100S with Rotax C box
Posted: Tue Jan 24, 2012 8:33 pm
by Kingfisher
Volkspares in Jetpark (Ithink) used to do that conversion, you could even get a new camshaft to enable you
to swop the heads around to get the carbs in front & exhaust at the back. If you contact Oupa G on the forum
he'll give you lots of info. They import a gearbox custom built for the BMW's and have a complete engine management
system and other bells & wistles for them.
Re: B M W R100S with Rotax C box
Posted: Sat Jan 28, 2012 4:29 pm
by johnnie wishbone
I wanted an engine with carbs rather than injection for a first project, I have seen people battle with electronic stuff and it is not really my field. The hawk flies OK with the 503, maybe a bit broekskeer off our 250M strip 2 up with no wind, wires and rising ground at one end etc. say no more.
It is a short engine and I hope it will not push the c of g too far aft as longer ones do, (have seen both 912 and jab versions) and it does not have back cylinders to try to cool. they change the cam to be able to turn the heads around in a tractor configuration as the exhaust ports is where the heat is but for a pusher this one is OK.
It was fitted to a thunder bird type thing in the UK but they were using 4 oil cooled coils like a car and I am short of a place to mount them, it sparks both sides each time it fires and I am looking for a light coil with two plug leads but know nothing about impedance and matching components?
Re: B M W R100S with Rotax C box
Posted: Sun Jan 29, 2012 3:36 pm
by Dobbs
Before you go any further with the BMW engine, as mentioned by Kingfisher, contact Oupa G, he is truly an expert in BMW engines fitted onto both Trikes as well as 3 axis planes. He / son has developed a state of the art engine management system, so no need to reinvent the wheel in this case

Re: B M W R100S with Rotax C box
Posted: Mon Jan 30, 2012 8:58 pm
by Jean Crous
Some of the modern cars, if not all , use what is called a coil-pack system. Speak to a big Autozone branch, or even Midas, they should be in the know about 2 plug lead coils.
Jean