I Designed It, I Built It

Here is the Horse Shoe Stator. You have to Index the Yellow Coil up Level. The Holes on the Outside Rim shows where the New Holes need Drilled. You have to Mill the Top Flat in that Area also. 2nd Design has the Slots added. I haven't had the New Design 3D Printed yet.

Here is the Back Side where you would drill the Holes. The Stator Snaps into the Jig, lind it up, turn it over on a Drill Press and Drill the (3) Holes. 2nd Design I'm going to use a Cheap 6" Rotary Table off eBay and you will be able to Mill Top Flat and Mill the Slots similar to the Factory Slots.

Thanks Rich for your contribution.

Here is the link to the original idea. I gave them all my research so they could make it to work with all the Old Singles and even some of the Old Twins. They don't have all these Engines to Test it on. Skidoo/Rotax rated these Old Engines Standard at 5500rpms, TNT's at 6500rpms, Blizzards 7500+rpms, so use different Timing.

https://www.rmstator.com/en_ww/products/points-ignition-conversion-kit-for-ski-doo-elan-stator-cdi-combo-1971-1996-rms900-100107

1971 340 Blizzard Free Air. Skidoo's Highest 36HP Production Single. In Race form was around 55+hp!

Their 250 Install video. https://www.youtube.com/watch?v=cw-aEVH31o4&t=60s

There is more new 3D Printing materials coming out each year. Could an Engine Case and Free Air Housing like these parts be 3D printed? The Engine Case probably doesn't see 200F. The rear Free Air Housing even less Heat.

Currently metal sintering is getting cheaper every year. Try this link for options.

https://3dprinting.com/metal/

For most People in the World, till they can show the difference between Casting, Forging, CNC Milling a part vs 3D Printing it. Cost vs Time it will be slow coming to the low end of the food chain. That rearend Free Air Housing is a Reproduction Casting, was $350, but not being made today. If you broke it into (3) pieces and welded it up, you could water jet cut some of it. Block Adapter Plate, Center Tube, Outer Plate. I was thinking of using a GPL Stater as the Center Tube to give me Electric Start.

How does that #350 dollar casting compare pricewise to just getting a whole used motor?

I wonder if it could be attempted to place a cracked casting in a metal sintering printer and just have the software make the laser outline the part and add new material to the outside of the part. Maybe even just add material to the cracked area.

How about instead of that someone creates a metal sintering gun to spray on metal over cracked sections?

Blizzards in the early 70's were Free Air Engines and were like Semi Factory Race Engines, so were built in Smaller Numbers and are very expensive if you can find one. I have never seen one in person, only photos. Even the TNT Engines are getting harder to find. I scored a 340 TNT Engine off eBay about 6 months ago. Somebody bought a Storage Unit at a Auction and it was on a Go Kart. They didn't know what it was. It's a Fan Cooled Engine, but use's same Cylinder as the Blizzard Engine, just uses a lower 10.5cr, 38mm Carb, and a Muffler. Blizzards used a Higher CR and a Tuned Pipe. Standard 335/340's 9.0cr, 32mm Carb were rated 20hp@5500rpms, 340 TNT's used 10.5cr and 38mm Carb and Muffler were rated 26hp@6500rpms, 340 Blizzards ??cr, 38mm Carb, used a Tuned Pipe were rated at 36hp@????rpms. I have never been able to confirm what CR and at what Rpms they were rated at. Out of all the production made Engines I have looked at 12.5cr is the Highest I have seen used. The Highest Rpms used on any Stock Production Engine was 7500rpms. On Avg a +1.0cr = 2hp. So a 340 TNT 26hp@6500rpms using 10.5cr, +1.0cr = 11.5cr = 28hp, 11.5cr +1.0cr = 12.5cr = 30hp. 30hp +20% for a First Generation Tuned Pipe = 36hp. So they could have used 6500rpms and made 36hp. The last restored 1972 340 Blizzard I saw was going for $5500. The Twin Cylinder Engine 340/440 TNT's and Blizzards are easier to come by. The Single Cylinder, TNT and Blizzard Engines are getting rare to find. The Standard 247/250(12hp@5500rpms) Singles started around 1963 and most Single Cylinders died out by the mid 70's, everyone wanted Twins and Triples. There were earlier Singles like a 148, 163, but I don't know what years they were made before 1963. They were very small HP Engines. The TNT's and Blizzards Singles came out around 1969 and died out around 1976. Only the Standard 247/250F (1963+) and 277F (1980+) were used up to about 2006. I want Electric Start, so I will probably make Adapter Plate and use that GPL Starter setup, it can also retain the Pull Start feature if you want.

It's probably a lot Cheaper still to just CNC Mill the Parts out of Billet Stock. For low number of Parts, you can find Billet Stock on eBay/Craigslist some times Cheap. I once found some 6061 Billet Plate 3ft x 5ft x 3.5" for $400 each, he had (2). A Billet Skidoo 670 Twin Race Head Retail is $400. A Twin Head is around 6" x 9" x 2.5". One of those 3ft x 5ft Plates diced up could make a lot of Heads. There is a Seadoo 650/657 Head on here that is the same Head Shell Size as my Skidoo 670 Head, same Bolt Pattern. To produce a CNC Billet Head was around $125ea when I looked into it. I doubt we will see 3D Metal Printing compete with CNC Milling in my Life Time. At one time, Parts were made for say $5, then wholesaled for $10 a 100% markup, then Retailed for $15 100% markup. Today that $5 part is wholesaled for 300%, then Retailed for 500+% markup. Everyone wants to be a Millionaire overnight. A Good example. I can buy a German FAG Crank Bearing for $8.50ea out of China if I buy Blocks of 25 shipped Free to my door. Each Twin Crank needs (5-6) Bearings, Singles (2) Bearings. Here, that same bearing cost $80ea. You can Buy a 80cc Billet Case for $650. Nobody is making a Billet Single Case for Sleds, but a Billet Twin Case is around $2,500+, Triple $3,500+. That 80cc Billet Case isn't much smaller than the 247 to 340 Sled Single Case.

Finding a Free Air Single, Twin, Triple, is getting real Rare. So Very Expensive.

Hi M. Gillen, discussion from snowmobile forum regarding the cdi conversion took me here. I am currently attempting the horseshoe cdi conversion on a Rotax single 335 . Can you share the Jig file?

J.O.