Why didn't Rotary ever catch on?

[Brian G. Wilson]

Ben,

The Aixro doesn't max out at 10,000 rpms....it has a max safe operating rpm's of 10,800 and there is a rev limiter. I've been reading the specs on the newest model and they put a new PVL ignition on it and rate it at 11,000 rpm's. All the manuals and info can be found here:

http://www.woelfle-engineering.com/Produkte/produkte_XR50rotaryengine_en.html

I have the Aixro and have many, many hours on it. Yes, it would be great if they would come up with a simple 2 speed option like the DD2 has. I think a 5 or 6 speed transmission would just make it scary fast and quite honestly, too dangerous. However, I have found as the operating manual states, that the Aixro works very well on a track designed for karting. Yes, it is going to run into issues at a longer road course that is shared by karts, bikes and cars. I know things are different around the country, but I have found that the tracks in the .7 - 1.2 mile length are the most fun for this engine as they don't have the tight, almost come to a stop hair pin corners. I have found the tracks that are .6 miles or shorter are not nearly as much fun to drive (for me) as you have to gear down to get the right rpm's for the tight, tight hairpin corners and the 80' straights between them.....when you are geared correctly, then the engine produces way too much torque & power and it becomes a handful to drive and you can get out of shape very quickly. On the newer engines, they come with Tomar clutches, not the Hortsman they used to come with. I would have to read the spec manual on my clutch, but it has varying tension springs you can use and I have mine where it engages around 3,500 rpm's but could put in another set of springs and have it engage around 4,000 rpm's if wanted.

As I stated before, this is not the end all, be all motor.....but it is fun as can be for what it is and how I use it.

As to the original question as to why they haven't become more popular may have to do with Renntech, the US importer for the engine. They list the SLR Aixro kart on their website for $18,285 and state that you need to add $1,200 for the building the kart for a turn key package. To me, it looks as though they are targeting rich, playboy types who want a kart parked next to their Ferrari or SLR Mercedes.
_________________
KEEP WORKING....millions of people on welfare depend on you !!

[Gary M Smith]

[Chris Hurst]

[Jean Stafford]

I think the reason it didn;t catch on was because, in my opinion, there was a design flaw.

The engine out there was limited to about 10,000 RPM because of the design of the ignition system. It was very out of balance, and the crank supporting it was small, perhaps too small. Over 10K the crank flexed and the magnets hit the stator, generally cauysing a lot of damage, expensive damage.

They did produce massive amounts of torque, and exceeded 50Hp, but the expense of over-revving them was too much.
_________________
Jean Stafford
Stafford's Racing
Dayton, Ohio
ROTAX Repair station,
jean@sgandt.com
Started Karting in 1959
"Some people are like 'Slinkies', worthless, but they bring a smile to your faqce when you push them downstairs."

[alan speyrer]

come on benn, you know you want one! heck i want to put two of them on a kart!