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grassman222
03-16-2011, 06:00 PM
Whats the difference between the CTLs that have the drive sprocket straight up from the lower one . For example a Takeuchi or Gehl compared to a komatsu ? I was told what the difference was but i cant remember what the answer was.

stuvecorp
03-16-2011, 07:45 PM
I was told the Takkie's(and sister versions) sprocket is like it is so the track is in contact with the sprocket more.

bobcat_ron
03-16-2011, 08:18 PM
Something to do with power, some kind of triangle and torque values, God only knows, but more contact with the sprocket is a good start.

Digdeep
03-16-2011, 09:13 PM
It's a bunch of marketing mumbo jumbo.

Contrary to what some OEMs will tell you, pretty much 80% of the torque/force used to drive a sprocket forward is only on two teeth/sprocket segments....regardless of whether you have a "high drive" machine, or 180 degrees of track wrap around the sprocket such as with a track loader or an excavator. All more "track wrap/contact" will do is spread out the other 20% over more sprocket teeth/segments.

Almost 90% of the torque/force is on one sprocket tooth/segment when in reverse..hence one of the primary reasons that wear/cost is increased in reverse.

Tigerotor77W
03-16-2011, 09:52 PM
It's a bunch of marketing mumbo jumbo.

Contrary to what some OEMs will tell you, pretty much 80% of the torque/force used to drive a sprocket forward is only on two teeth/sprocket segments....regardless of whether you have a "high drive" machine, or 180 degrees of track wrap around the sprocket such as with a track loader or an excavator. All more "track wrap/contact" will do is spread out the other 20% over more sprocket teeth/segments.

Almost 90% of the torque/force is on one sprocket tooth/segment when in reverse..hence one of the primary reasons that wear/cost is increased in reverse.

Quoted for truth.

Edit: Oh -- I should add, though, that there may be other benefits. The ride could potentially be affected by sprocket placement, and debris could be shed easier with one design vs. other. As far as power transfer, however, that really isn't an issue regardless of the relative positions of the sprocket and rear idler.

grassman222
03-16-2011, 10:16 PM
o ok , i could remember . a friend of mine has a komatsu and i like it but i ran a takeuchi the other day and that one seemed to push the pile alittle better . i dont know . i geuss its whatever i like in the end right? Thanks everyone for the info keep it comin

grassman222
03-16-2011, 10:17 PM
i geuss more sprocket contact would be better for pushing but i have no idea

stuvecorp
03-16-2011, 10:40 PM
It's a bunch of marketing mumbo jumbo.

Contrary to what some OEMs will tell you, pretty much 80% of the torque/force used to drive a sprocket forward is only on two teeth/sprocket segments....regardless of whether you have a "high drive" machine, or 180 degrees of track wrap around the sprocket such as with a track loader or an excavator. All more "track wrap/contact" will do is spread out the other 20% over more sprocket teeth/segments.

Almost 90% of the torque/force is on one sprocket tooth/segment when in reverse..hence one of the primary reasons that wear/cost is increased in reverse.

It wouldn't surprise me if it was all marketing 'mumbo jumbo'. :)

I feel the TK machines would be much better having the track extended backwards...

Digdeep
03-17-2011, 12:08 AM
o ok , i could remember . a friend of mine has a komatsu and i like it but i ran a takeuchi the other day and that one seemed to push the pile alittle better . i dont know . i geuss its whatever i like in the end right? Thanks everyone for the info keep it comin

You are absolutely correct...it comes down to the one that best fits your needs. Much of the "pushing the pile better" that you feel is a function of traction force through the sprocket to the track, track surface on the ground, track tread design, machine weight and engine hp.

I have a formula for traction force in my classroom and I'll post it tomorrow. It's important to remember that traction force is only a calculation and does not always translate into more traction due to the other factors that affect traction...track length, weight distribution, tread design, soil conditions, etc.

AWJ Services
03-17-2011, 08:38 AM
o ok , i could remember . a friend of mine has a komatsu and i like it but i ran a takeuchi the other day and that one seemed to push the pile alittle better . i dont know . i geuss its whatever i like in the end right? Thanks everyone for the info keep it comin

Every brand has it's own different positives and negatives. What you will find is that all will be productive overall with each one being a little bit better in one situation and weaker in another.

Find one you like and are comfortable in and thats the best choice.

Digdeep
03-17-2011, 11:00 AM
You are absolutely correct...it comes down to the one that best fits your needs. Much of the "pushing the pile better" that you feel is a function of traction force through the sprocket to the track, track surface on the ground, track tread design, machine weight and engine hp.

I have a formula for traction force in my classroom and I'll post it tomorrow. It's important to remember that traction force is only a calculation and does not always translate into more traction due to the other factors that affect traction...track length, weight distribution, tread design, soil conditions, etc.

Here is the formula. this will tell you how much force you have going to each sprocket. The result you get from dividing by 6.28 is the force 1" out from the drive motor shaft. You then deivide by the sprocket radius to get the force out at the "track".

Drive Motor displacement in cm3 × 0.61 (convert cm3 to in3)= ??? × maximum pump pressure= ??? ÷ 6.28 (π×2)= ??? ÷ Sprocket radius= lbs force to sprocket per side

grassman222
03-17-2011, 04:22 PM
anyone here anything bad about Gehl track loaders?

grassman222
03-17-2011, 04:24 PM
I drove one the other day with a grapple bucket. It was nice all up until the track jumped off. A stick jammed in the track and popped it off when i turned . Other than that i kinda liked it .