Why wouldn't this work?

[JohnF]

Couldn't you just change out the UHMW cog when the belt reaches (lets say .8%)? If the track stretches at the same rate across the lenght, than you'd just have to have a cog with a larger pitch (and larger dia, whatever that would be). Seems easier than to move an axle back.

Need to change the sprocket diameter to take up the extra length in the track. The outer diameter of the sprocket is already at limit. We could add shims to the valleys in the sprocket to take some up. The cost of this would be to reduce the contact area of the sprocket teeth to the track cogs.

[Bw6]

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I've been enjoying this thread for a while thought I would throw in a few ideas of stuff I tried a couple years ago. To compensate for track stretch I designed a "track takeup". Anybody who has been around a belt conveyor knows about it. This takeup could be installed on the front axle or rear depending which end is being used for driving the track. What you see is a manual takeup, but it could easily be automatic by using a compression spring. This would maintain proper track tension through out the life of the track. This eliminates tire pressure or tire diameter from the equation.

[prailleraide]

Heres an idea i have for a long term project

The idea is to build trackframe for each side, a bit like a snowmobile. Remove all tires, and replace the front wheel flange with a sprocket, chained to transmit power to the trackframe. The front of the trackframe should be 1 or 2 feets forward the original front axle. Should use snowmobile axle shaft fitted 4 cog wheels. Tracks would be made with snowmobile tracks with the same pitch and joined to keep the pitch. The rear of the trackframe should have a track tensionner.
Starting with this, you can add suspension to the trackframe, with dual buggey wheel or something like that

Many cons of this :

floatation ?
is the brake system will be efficient enough to brake a side ?
finding good idler wheels

I am building a set of tracks (with tires) with good condition used snowmobile tracks, the advantage of this is getting traction from the interior of the tracks so the possibility to remove chains to the 2,3 and 4th axle.

[JohnF]

The Adair Classic track design reduces the effect of belt stretch. I have not done the math to figure out to what extent it changes the design.

[Moosetalker]

Great thread. Good tech thoughts here about tires, drive cogs, track stretch, etc

I have burned a few brain cells giving a bit of thought to a dedicated track set up. being as I wish to run adair type tracks year round.

Thought about using hydraulic drive motors to power the rear wheels/drive cog, I have 3 commercial Zero turn mowers that are hyd drive. using both gas and diesel 23-25 hp engines. they seem to have lots of torc especially when they are not driving the mower deck.
Top speed is 11-12 mph 19 + kmh with 24" turf drive tire. Dropping tire size to 22" would lower speed and increase torc. Braking is instant and positive. and a big plus would be counter rotation side to side. A raised mount over the rear axles with a drive chain set up in the sameway as the Argo trans would give a gearing option.

The drive motor/power pack is expensive to buy new. Not a good thing .

Good things two short drive chains only 4 sprockets only

Cost wise it might be feasible If the existing Argo Eng and tyranny were no good. and it is due for rechaining or one could salvage the required parts from a wrecked mower..... maybe if one of mine was to get run over by say a tractor... Nah the boss {wife } would kill me.