2014

[7 skulls]

The ohlins system was developed for 2WD motorcycles. The system on a snowmobile would replace not only the chaincase but the two clutches as wel , I believe.

 

[sledhead23]

I fail to see what is gained with the Ohlins system? They still used the bike's gearbox so it's not like it would replace the CVT. The CVT is the "gear box". Why would you want to have an expensive and complicated pump and two hoses to replace the chain case? The system weighs over 17 lbs, I bet that is similar to or heavier than a chain case.

If a guy really wants to replace the chain case than go with a belt drive. A broken belt can be replaced in the field. Belt drive is simple, light weight and cheap to produce. I think Polaris's version is a POS but the aftermarket versions like the C3 or Crazy Mountain Machine are reported to work pretty well. http://www.crazymtn.com/sifiso/pages/cmxds.html
https://www.c3powersports.com/category/ ... yncrodrive

With this system they use the gears to control the variable ratio (a hydromechanical cvt), but what I am talking about is a HS cvt which means you don't need the gears or the traditional friction based cvt. in this system they control the variable ratio I believe by changing the pitch of the driven pump so at different rpms (just like when they flare the blades on a plane) they can change the pitch of the internal turbine to control, they are called variable displacement pumps. So, with this you would not need any clutches or chaincase

 

[De250r]

Fusion power? Nobody's brought that one up yet? Was kinda busy in here today. 2 days 16 hours 43 minutes.

 

[1nc 2000]

Throw in a rear axle drive too while your at it.....

 

[Mighty]

Throw in a rear axle drive too while your at it.....

Did you see the supertrax article about the guy that converted a Doo to this? Better traction and better fuel economy. They said he was trying to sell the idea to the sled manufacturers

 

[sledhead23]

Throw in a rear axle drive too while your at it.....

Lol that would make the ultimate sled. Can you say bye bye competition. Too bad most of these ideas (mine included) are speculations and dreams

 

[1nc 2000]

Throw in a rear axle drive too while your at it.....

Did you see the supertrax article about the guy that converted a Doo to this? Better traction and better fuel economy. They said he was trying to sell the idea to the sled manufacturers

Yep.

 

[Paraclete]

Fusion power? Nobody's brought that one up yet? Was kinda busy in here today. 2 days 16 hours 43 minutes.

I heard they did patent a flux capacitor that would work at sub zero temps.

 

[Dano]

With this system they use the gears to control the variable ratio (a hydromechanical cvt), but what I am talking about is a HS cvt which means you don't need the gears or the traditional friction based cvt. in this system they control the variable ratio I believe by changing the pitch of the driven pump so at different rpms (just like when they flare the blades on a plane) they can change the pitch of the internal turbine to control, they are called variable displacement pumps. So, with this you would not need any clutches or chaincase

Yes, the drive pump is usually a variable displacement pump which is often a piston pump. This is the pump that the operator controls flow (speed) by increasing the angle for more flow. More angle=more flow=equals more speed to driven pump which is a fixed pump that would be connected directly to the track drivers. Want to back up sled? angle the variable pump (swash plate) in the opposite direction and it reverses the fluid flow and backwards you go. These systems are often connected to a sub transmission for more versatility in speeds. Thats the basics of hydrostatics that I work with and I'm sure the new smaller systems found on bikes are much more complex. I'm pretty sure the system on bikes are controlled through a throttle position sensor so that the demand of more flow for variable pump is match for enough HP from engine RPM.

Dan

Dan

 

[dmanrider]

Dont forget the apexs use a reduction gear off the crank because the motor spins too many rpms for cvt clutches...with some kind of hydro trans u could do away with this power robbing gear and get ride of that weight and space...

 

[Off Trail Mike]

Are we at a 100 yet?

Pretty sure Yami has a patent on a crank based reversing planetary drive that allows reverse and forward and a gear reduction inside the engine, same as turboprop aircraft. It allows them to easily adapt their high reving bike engines to sleds while maintaining reverse without all the gears they presently have in their chaincases..

I guess theoretically you don't need a chaincase either with this setup, rather a belt drive would do it, and since they (cog belts like Polaris ProDrive) are about 98-99% efficient, it would add to track HP.

Personally, I don't think any of this is on the table, but a new sled is...

Turbo/NA options coming with tracks from 128 -144, oh yeah, and a flux capacitor for the jump to lightspeed...

OTM

 

[timebomb]

Fusion power? Nobody's brought that one up yet? Was kinda busy in here today. 2 days 16 hours 43 minutes.

I don't think boiling down Polaris Fusions for fuel will do us any good. Though that would make those sleds useful. Lol

 

[natedawgedog]

Hydraulic drives have been done in the 70's by yamaha and arctic cat. so thats not an industry first, I did a google search and turk (dont know if it was the same legondary turk that used to be on here, r.i.p.) was the one to ask that question on another forum ( http://www.snowmobileforum.com/vintage- ... drive.html )... just sayin. I think I would want to keep my clutches and belt just because the ability to tune it to do what you want IE drag racing, hill climbing, boondocking trail riding, corner to corner wfo riding. I work in an industry were we use hydrostatic drive systems for alot of things and the ride and "jerkyness" of that type of drive would bury the back end of a sled just as fast as a backhoe could dig the same hole.

 

[morrisond]

Jerkiness in an HST? Something must be wrong with the one's your driving. My only real experience is with Tractor's and lawn Maintenance equipment - but the HST in my Tractor (A John Deere 4520 - 60 HP about 157 lbs. of torque) is smooth as silk. When loading and doing fine work you absolutely creep with it at .25 mph or less and smoothly accelerate up to top speed.

If you spin a Nytro Motor to 11-12,000 RPM 180 HP should be easy with no need for gear reduction or forced induction if you use HST.

 

[fourload]

In the early 70's I rode a SL433 Yamaha and I distinctly remember my Dad's friend had a hydrostatic drive Yamaha. It always gave him problems but I am sure they could perfect it now!!