British & European Bikes, Build Threads & How-To’sBuild threads, tech Q&A and conversations centered around custom-built motorcycles from the UK and Europe
A while back I started shopping around for an air-cooled 2-stroke snowmobile engine that I could possibly put on a custom made motorcycle. Instead, I discovered that Fichel-Sachs had made a 303cc air-cooled rotary(wankel) engine back in the late 60' into the 70's with 25hp and a sweet sweet pull-starter. This was an optional engine on old Arctic Cat sleds. It would pull the sled to around 35mph but from what I understand it could pull almost anything. After months of shopping/searching, I was able to get my grubby hands on one and the project had it's first component.
I finally settled on the fact that I'd have to make a frame from scratch to satisfy my needs. I knew I wanted a skinny lane-splitter and long and low.
It's a German made engine, so this is my first European bike forum thread.
Enough of the story telling, here are my first pics of this build, aptly named "Matterhorn: Ice, Wind & Freedom"
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Join Date: Sep 2010
Posts: 77
More Photos
The whole rig is 8 feet long and only 34" at the top of the steering stem.
My plan was to use the snowmobile's original CVT belt drive and run a jackshaft to the rear with a chain. This has proven to be not as aesthetically pleasing because it sticks too far out on the left side. I haven't come up with a solution as of yet. I'm considering an aftermarket CVT or perhaps a stand-alone transmission from some other small motorcycle. The donor bike was a 99 CR125 for the forks and wheels however I'm going to order some 21" rims for the front and back.
The gas tank will fit under the top tube and I'm going to start into that this week.
Thanks for looking and hopefully I will have more progress photos soon.
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Join Date: Sep 2010
Posts: 77
Thanks
I appreciate the interest friends.
I think I'm going to start working on the tank this weekend. I'm having a hell of a time deciding/finding a transmission setup for this thing to get power to the rear wheel. I see a lot of people who've built diesel bikes use CVTs. I have to get it all squared away before I put the exhaust together and the foot peg location as well.
-cheers
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Join Date: Jun 2010
Posts: 2,130
Sweet!!!! This is a cool motor! I have been collecting these for a long time (and have only got a hold of 2 of them!)
I had an RE5 but a dude offered me a crazy amount for it and I had to sell it.
I saw somewhere not too long ago where a dude hacked the 6 speed tranny off of like a CB360. Then just welded the holes back up with scrap aluminum, filled it with some gear oil and it was good to go. he had to machine the input shaft to accept a standard style clutch. The whole unit worked perfect.
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Join Date: Oct 2009
Posts: 550
Dude, you're makin engineering a from-scratch build with a non-standard motor look WAY too easy! Can't you throw in a couple pics of how something didn't work out quite right and you had to re-do it to make us hacks not feel so bad?
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Join Date: Jun 2010
Posts: 2,130
I think you should put two side by side! LOL
these motors had a pretty low torque rating, especially in the bottom end. maybe thats why they were all on a cvt tranny?
Have you seen the shifter kart modern Wankel motors? http://www.youtube.com/watch?v=YBHuH...eature=related
Update:
I have been doing some parts fiche searching and it looks like a 3/4" jackshaft with a 3/16 keyway is what Arctic Cat used, so I will be able to simply pick up a mini-bike jackshaft and fab up a mounting/adjusting system for the CVT....trying to utilize a donor transmission looks like a real pain in the ass, plus I like the look of nothing on the handlebars but a throttle.
~Alex