Tracksled / Snowdog help please

[MeatSweats86]

Long time looker and first time poster here. I live in the land of 10,000 lakes (MN) and looking to build a homemade Tracksled/Sleddog from an existing vintage Arctic Cat snowmobile.

http://www.diygokarts.com/vb/showthread.php?t=40026&highlight=tracksled

https://www.youtube.com/watch?v=MI0GVSP0fp4&feature=youtu.be


The thread above an youtube video has given me inspiration and I just wanted some other peoples thoughts on my build list. I am looking for torque vs. speed for this project to haul my gear and myself and 2 kids around. I know gearing is going to be my biggest issues and the list below is my guesstimate as to what I plan on using for this build and the cost.

I am planning on buying the sled this weekend, so I don't know what gearing it has, but my intentions are to use the 6.5HP Predator with a 2:1 Wet clutch as someone mentioned on the above thread and mount a gear in the existing snowmobile jackshaft.

I've got mediocre mechanical skills and tools, grinders, saw, welder, space in my garage, a lot of beer and a can do attitude.

Can anybody point out any flaws they see with my list or idea before I buy the sled this weekend and tackle this project? Is the 6.5HP Predator paired with a 2:1 Wet clutch a good option or should I plan on doubling my budget for a larger engine and CVT?

As long as it moves faster than my feet and is reliable is what I am aiming for.


Vintage Arctic Cat Snowmobile -$50
6.5 Harbor Freight Engine $120
2:1 Reduction Gearbox Kit for Honda 6.5HP GX200 Engine (22mm) $129
Engine Mounting Plate 8-3/4'' x 7-3/4'' with Lips - $13
Throttle Linkage Kit for 6.5HP Clone / GX160 or GX200 Engine - $9
Throttle Cable - $10
Brake Cable -$10
Jackshaft Sprocket $10
Metal tubing to build frame - $50
Misc tools and equipment $100
Use the handle bars , existing Jackshaft and gear case from the snowmobile.

 

[Kartorbust]

Uuf dah! That's a might large project dont'cha know? I'm also from the land of 10,000 lakes, or was really. In a way I feel like you'll be miles ahead just fixing up that sled and using that and/or buying a Arctic Cat Kitty Cat size sled used. The kids sleds from what I remember just use a centrifugal clutch with a jackshaft to move them around. They used smaller 125cc industrial engines. Just my opinion.

Trying to mate up a wet 2:1 clutch to a Predator 212 is going to be about as expensive as a CVT setup. With the CVT you'll get a lot more speed because on how they work than a 2:1 with additional gear reduction.

 

[MeatSweats86]

Trying to mate up a wet 2:1 clutch to a Predator 212 is going to be about as expensive as a CVT setup. With the CVT you'll get a lot more speed because on how they work than a 2:1 with additional gear reduction.[/QUOTE]


Thank you for the input Kartorbust . The motor is shot on that sled, otherwise I would try fixing. The kid sleds around here cost more than an older full size sled, otherwise I would consider that.

I was hoping to find a wet clutch to install as I have read CVT's struggle with the wet conditions and heavier weights I plan on pulling and wet clutch would be more durable and only allow half the speed which I am good with.

 

[Kartorbust]

You could put a cover over the CVT belt to help keep it dry or do what sleds do and just completely enclose the area to help with that. Basically just copy similar aspects of the engine compartment on the sled and go from there.

 

[vpd66]

I'm another vote for the CVT and skip the wet clutch. Also that old Arctic cat most likely has a steel cleated track. These were a lot more heavier then an all rubber track and they were more maintainace. They have a tendency to break cheats. Also they suck for traction on ice.https://youtu.be/eo9dKtEWk9Q
Check out this video. It is the most simplest Tracksled build that I've seen.
I've been researching these for a few years and I'm almost ready to build. One thing that everyone that uses a standard snowmobile says they a little too narrow at 15". Most of the manufactured Tracksleds have a 20" wide (or wider) track. Also the most common snowmobile track size it 15"x121" and it is about 20" too long. At 121" to make a Tracksled like in the video it would end up being a little over 5ft in length. In the video the guy shortened his track to around 103" and that would make it about 4ft long (or 4ft of track contacting the ground). I know all of this track dimension stuff sounds like small details but it makes or breaks the performance of a Tracksled.

 

[Kartorbust]

One thing I completely forgot about was lighting. Once November/December roll around, it's dark by 5pm. If you already have the 212 Predator, then just use that and maybe get a battery for an LED light. If you haven't bought an engine, I'd push for the Predator 420 or even a Duromax. Both will have or can have electric start and have at least a 3amp or higher stator/charging coil. That will be helpful to keep a light on, especially out on the lake and the extra torque will be nice. Speed will remain the same, but the torque will be nearly doubled the 212. That will make you use a larger CVT like a Comet 40 series or 44 (difference is the 40 series top end is 1:1 where as the 44 has a 1.43:1).