Track Tuners....What are they?

[riotwarrior]

OK so let me get this straight; most all tracks can benefit from the tuners, however some are more forgiving than others.

Now if you can DROP the drive chain off the one axle and just power front and rear axles, that in essence would be the same as using track tuners correct? If so then this would be my preferred option myself.

Didn't know this would be such a great topic for discussion but lots of great info here!

[foxvalley]

No, most all tracks don't benifit from the tuners.The tuners are like a big bearing that let the wheel free spin. On an 8x8 two tuners are attached to the middle two hubs,which let the center two tires free spin.Without tuners, if your front tire is 22",for example, and the center two tires are 28"( exagerated for my example),for every revolution of the front tire,the center two tires,being 28", have to "slip" 6" for every revolution.22"-28"= 6".Its more of a pop! or bang! that you will hear every revolution.This is called chain windup.Rubber trying to slip on rubber 6"if using rubber tracks, well you know. If all 8 tires are within an inch,very little chain windup happens.etc.With tuners,you elliminate all windup by letting the two center tires free wheel.
Yes, if you could drop the chain on the center tire of a 6x6,exactly the same thing,center tire is free.

[Buzz]

I don't see any benifit of useing tuners on certain track types, if your tires are close to being the same size,reguardless of tread design.Chain windup just doesn't happen,and if you dont need wheel spacers to run your tracks,like the pro series,or argo 13"plastic tracks, for example,why would you put undo stress on the hubs by extending them out 2,5" if its not needed.

the ultimate option would be the ability to disconnect the drive power to the center(s) wheels w/o having to space them out. Disconnecting is where the benefit comes into play. Whether or not a person wants to run a wider wheelbase and run a certain type of track just depends on where they live and what conditions they're going to be trying to deal with.

[Buzz]

it would be cool if the machines would be designed with a "coupler" inside the machine that could be removed...preventing the outer axles from being driven. The centers would have idler axles I guess that would still transfer power via the chains to the rear axle. Comes down to space really.

[Buzz]

If you choose not to put tuners on an elevated belt track, you will NOT get a "pop" or a "bang". You will simply spin you center tires faster than the ends. It will actually keep the correct side of the chains loaded, very similar to what argo attempts to accomplish with their "indexing" pattern for rubber tracks. It's just exaggerated wheel spin that wastes some power. Gear reduction makes up for some of that. Tuners make it even better. But it wont' destroy your machine. It's a design that actually ensures that your machine will see the centers as the "largest" in regards to keeping the load away from the tensioners. You could actually put smaller tires in the center (I don't know why you would want to do it), and the machine would still spin them faster than the corners. It's still load on the chains similar to climbing a hill or towing a trailer, and goes away with tuners for an even better working system.

[Buzz]

popping or banging typically comes from loose chains where when one side tensions up, all the excess slack makes it's way to the other side and the chain "skips" a tooth. This is not good and can happen with any machine with any track...and even when running just tires. It's true!

[foxvalley]

The noise im referring to is the slipping of the tire inside the track,I seem to hear this at higher speeds.

[Buzz]

The noise im referring to is the slipping of the tire inside the track,I seem to hear this at higher speeds.

Which track and tire combination? It's funny how it doesn't take much in the way of tire lug height to grab or load crossers. Geez, even crosser spacing and crosser width can come into play.

[JohnF]

it would be cool if the machines would be designed with a "coupler" inside the machine that could be removed...

This could be done by re-engineering the sprocket to use dogs like a synchromesh gearbox. And yes, space is a problem in the area we are talking.

If you choose not to put tuners on an elevated belt track... You will simply spin you center tires faster than the ends. ...

This really isn't a very good description and could lead to confusion concerning how these things work. The tires spin at the same rate (RPM) because the axles are fixed to each other via the chain/sprocket system. This is the case no matter which track system you choose.

Chain windup, which is really axle windup, happens because we mechanically fix our axles at two places; the chain/sprocket interface and the track/tire interface. The track/tire interface is a belt/pulley system. If the pulleys are all the same effective diameter then there will be no windup. Unfortunately these pulleys are inflated rubber (will change size dynamically) manufactured as tires (already different sizes statically) so there will be windup issues and stresses will build that will need to be relieved. This is the case no matter what order you put your tires in.

The Argo strategy of sizing the tires and placing them in a certain order is designed on the idea that stress relief happens in the belt/pulley system via pulley slip as tires slipping on the track and not tires slipping in their wheels. The order they've chosen is to: 1 - Reduce ratcheting of chain tension (top/bottom/top/...) to reduce chain tensioner problems. 2 - put the pulley with the most stress in a position where it will be least restricted. 3 - Reduce anti-steering force.

The issue is that on some track systems such as rubber tracks the lesser restriction on the tire with the most stress (#2) still isn't low enough to allow the belt/pulley stress to be released via slipping all that easily and you load the machine by dragging every pulley on the belt like a big brake, or even better, a giant rubberband. The stress will build in the system searching for the weakest link to release itself. (Like chains over sprockets or axle flange welds.)

Track tuners disconnect the middle pulleys taking them completely out of the equation. They do not remove the possibility of axle windup as you still have a chain/sprocket system working against a belt/pulley system but they do reduce the probability by the number of removed axles. Tweeking the tire pressures of the two remaining tires to get them to an equal effective diameter virtually removes the problem of axle windup. This is the case no matter which track system you choose.

Although it is true that technically all track systems will benefit from the use of track tuner type technology it is practically not beneficial for track systems with lower coefficients of friction between the tire/track because the stress always clears by spinning the tire in the track and the stress never builds up to the point of totally over burdening the machine. Runamuck tires in Argo plastic tracks comes to mind. Each track/tire system will need to be evaluated to determine how beneficial track tuner technology is in that system.

If we look at track systems that I think Buzz is calling "elevated track", that we can recognize when we see that the grouser pitch increase as the track changes direction at the outside tires we should note that the effective diameter of the outside pulleys is the diameter scribed by whatever the grousers are connected to (belt/chain) and the effective diameter of the inside tires is the diameter of the tires themselves. This is usually a pretty large proportional difference as the designer will seek a design that isn't too easy to walk out of. Every track system of this type will benefit from track tuner type technology.

[Buzz]

JohnF- thanks a bunch for adding that.

I'll add a bit more, hopefully a better description. Anyone's eyes hurting yet?
All chained axles and therefore tire speeds will remain the same (minus factory imperfections at the same psi) if all hubs are left connected.
You are correct.
To be more clear, (I forget sometimes what I've written as I've done it multiple times and want people to understand it), when I say "spin faster" I mean that "driven" center axles with this design (actually all designs to some extent 2* to necessary tire indexing) "drive" the center tires at a faster speed than the "track-components" (to be specific) are moving under them.
All track designs will suffer this to "some" extent as a necessary indexing pattern of tires keeps the tension on the side of the chain opposite the tensioners.
At the same time, this "requires" some level of relief or slipping of the center tires (and the rear tire to some extent on an 8-wheeler) as all chains will remain loaded when the machine is moving. You always want the axles to drive themselves via the power transfer.....what you do not want is the belt/pulley effect you describe to act upon the tires themselves. End-wrap tires can be driven by the track (via this belt/pulley effect you describe) at a speed faster than the tires should be driven if the chains are transferring power like they should....like they should if the they are indexed properly. This is where you can you can trash your tensioner, wear blocks, or get the over-ratcheting effect.
How easily the tires are able to slip does come into play, even if they're indexed properly.
If the track components are greasy or icy, no problem. But even weighted rubber on top of closely spaced "wide" UHMW crossers (individual as to break contact) still requires horsepower to spin.
If a tire is required to slip...at all..it's going to add load to a chain and use some extra power. More slipping required, more extra power. Just the same as trying to spin heavy mud-tires faster in deep mud. In all machines the vehicle weight is added to this over the center tires. Newer machines even more with the corner axles elevated in the frame.
All tracks have tires indexed in this fashion to require at least "some slip" when necessary in the name of preventing undue wear and tear on the machine. It has to be done. It helps to protect the tensioner (if fixed) and over-ratcheting on non-fixed tensioners like you describe. And it helps to prevent the track from over-driving certain tires.
Instead we shoot to always have the tires over-drive the track so as to keep the chains loaded properly.
It doesn't take much tire rotation to load or unload a chain, and our indexing pattern is a must at the moment It is enough so that some slipping of the centers is required, and the potential for the track (and tire treads) to resist is always present, which is why I like tuners so much even when a person "thinks" that a center tire is going to be able to slip easily on an all-UHMW track.
Again, you don't have to use them. Indexing in very important either way. Your machine lasts longer if you save those "heavily loaded" requirement of the drivetrain for only when you need them....severe climbing, towing, navigating etc.
I honestly do hope that helps at least someone understand it a bit better.

[Old Tucker]

Thanks John and Buss. for your input on this. Our Argos are not built like a tank where brut force over rides friction. They may drive like a tank but they are built to be light as posable. Every little bit helps as I said before. Why not try to make it run as smooth as posable. And if it takes track tuners to to relieve some of the tension on the chains. Then do it. Its a win win . on all accounts.

[radar]

Are track tuners more for 8 wheelers or should they be used on 6 wheelers also ?

[JohnF]

With an "elevated belt" track design you should use a track tuner - 6 or 8 wheel. Otherwise it depends mostly on how easily the tires can relieve stress without tearing/breaking/binding up the machine. According to those that have done extensive testing and from what appears to be group consensus, plastic tracks like the standard/super tracks produce by Argo work fine without track tuners and solid rubber tracks tend to gain performance using tuners.

I guess I'm saying that the track design matters more than the number of axles that exceed 4.