Does lug height change the final drive ratio on a snowmobile

[ckf]

5 minutes ago, Mileage Psycho said:

Johnny sent a text about a month ago to say hello, he's a good guy

 

Stopping for a break at the tree

 

I always liked him

Just now, f7ben said:

tell him to pop in here Vince

[Momorider]

22 hours ago, BOHICA said:

Check this shit out....  So I was at safeway getting my lunch this morning.  Got a sammich, a banana, a cup of grapes....green and red intermingled in the same cup,  and a buy one get one free yogurt parfait.....  So I got two!!!!  America, Fuck Yeah!!!  Anyways when I got to the check out stand I told my coworker, that I know people who are very very smart on an internet chat room.  So I told him that I could get the parfait with blue berries and strawberries go faster at the check stand then the free one that had strawberries and pineapple even though they are the same size....  I told them you have to think of a conveyor as a wheel and the larger it is the faster it goes due to the final ratio of the conveyor being changed by the thickness of the belt....  So I set the blue berry/strawberry parfait on a little plastic round tin thingy of icebreaker gum......  and the other one with pineapple and strawberries directly on the conveyor.  So my blue berry parfait was at least and inch taller or so do to being on a "thicker" belt.  I told my buddy prepared to be amazed!!!!!  And had the checker person turn on the conveyor.....  Well fuck me they both arrived to the checker person at the same time   I figured the blue berry one would have pulled out at least a 1 parfait cup lead being on the thicker belt or taller lug by the end but it didn't.  They stayed equal in the race the whole way.  

 

No parfait flick  

[Kev144]

Fucking larue was a legend in his own mind.

[Highmark]

17 hours ago, Legend said:

A 7 tooth 2.86 drive gear can only be one diameter. Same for a 8 tooth 2.86, or a 9 tooth 2.52, etc. 

 

So comparing apples to apples, a different lug track on the same tooth drive of the same pitch, it makes absolutely no difference. 

 

edit. maybe you were saying the same thing and i just didn't read it right?

if so, ben is still a faggot

To clarify what my Polaris snowmobile engineer friend was saying.  This is generally ALREADY calculated in the sprocket pitch diameter however not all sprocket mfg's do this correctly.  A correct sprocket will measure smaller than the actual pitch diameter.  I will say he didn't clarify it very much.  I believe this is some what Arctic Crusher was saying as well.  

Pitch Diameter = Teeth x Pitch/ 3.1416 (Pi)

 

Edited September 14, 2016 by Highmark

[Legend]

Im not sure what you are trying to get at. 

 

Nothing in your illustrations can change the final drive ratio EXCEPT, if the nubs of the track run on the top of the drive cogs. And that would push the track out farther which would change the ratio. But in reality that could never happen because the drivers would then ratchet on the track. 

If the drivers aren't made correctly, they will not proper fit in the track and will either ratchet or wear out very fast. If the pitch is slightly off, it will wear, if the diameter is incorrect, it will ratchet. 

Again, its not rocket science. Simple math.

 

I didn't read what crusher had said. 

[Highmark]

11 minutes ago, Legend said:

Im not sure what you are trying to get at. 

 

Nothing in your illustrations can change the final drive ratio EXCEPT, if the nubs of the track run on the top of the drive cogs. And that would push the track out farther which would change the ratio. But in reality that could never happen because the drivers would then ratchet on the track. 

If the drivers aren't made correctly, they will not proper fit in the track and will either ratchet or wear out very fast. If the pitch is slightly off, it will wear, if the diameter is incorrect, it will ratchet. 

Again, its not rocket science. Simple math.

 

I didn't read what crusher had said. 

Jesus, I'm not saying anything about changing the final drive ratio.  Just giving further explanation to the former Polaris engineer's explanation on where the actual pitch diameter is.  He stated as did I that lug height has no impact on final drive ratio with all other inputs constant.  

[Legend]

44 minutes ago, Highmark said:

Jesus, I'm not saying anything about changing the final drive ratio.  Just giving further explanation to the former Polaris engineer's explanation on where the actual pitch diameter is.  He stated as did I that lug height has no impact on final drive ratio with all other inputs constant.  

Then quit trying to act smart because you're aren't coming across that way. Stop trying to make it more complicated than it really it.

 

Its done, it's over, we agree on the same thing. 

[Highmark]

1 minute ago, Legend said:

Then quit trying to act smart because you're aren't coming across that way. Stop trying to make it more complicated than it really it.

 

Its done, it's over, we agree on the same thing. 

 Sorry I was posting over your head.   Carry on.  

[Legend]

26 minutes ago, Highmark said:

 Sorry I was posting over your head.   Carry on.  

No you didn't. But I didn't need to have an engineer tell me the answer to this either. 

Good thing you know people smarter than yourself. Life can be rough when you're dumb. 

 

[Highmark]

1 minute ago, Legend said:

No you didn't. But I didn't need to have an engineer tell me the answer to this either. 

Good thing you know people smarter than yourself. Life can be rough when you're dumb. 

 

Must be tough looking in the mirror each morning for you.  

You don't know the history of this and why outside engineer's opinions were brought into it in the first place.   A guy on the old forum was making large bets that lug height changed the final drive ratio with everything else constant.   Nothing anyone here could say or show would work for him.   The question was posed to the former Polaris engineer to settle the bet from an outside source.  Keep talking shit about something you don't know about though.   Its working for you.  

[Legend]

40 minutes ago, Highmark said:

Must be tough looking in the mirror each morning for you.  

You don't know the history of this and why outside engineer's opinions were brought into it in the first place.   A guy on the old forum was making large bets that lug height changed the final drive ratio with everything else constant.   Nothing anyone here could say or show would work for him.   The question was posed to the former Polaris engineer to settle the bet from an outside source.  Keep talking shit about something you don't know about though.   Its working for you.  

Wow, a guy dumber than you??

Thats a special kind of stupid.

[Highmark]

Just now, Legend said:

Wow, a guy dumber than you??

Thats a special kind of stupid.

Keep trying "Legend."   What are you a Legend of? 

[Legend]

28 minutes ago, Highmark said:

Keep trying "Legend."   What are you a Legend of? 

Haha you just won't stop will you? 

That ego of yours just a wee bit fragile is it?

 

Its just a name I picked off the side of a trailer. But this "Legend" had owned you over and over in this thread. 

 

Your turn I guess...

[Highmark]

7 minutes ago, Legend said:

Haha you just won't stop will you? 

That ego of yours just a wee bit fragile is it?

 

Its just a name I picked off the side of a trailer. But this "Legend" had owned you over and over in this thread. 

 

Your turn I guess...

Legend in your own mind is an accurate phrase for you.

My first Mountain sled was a 2002 Doo Highmark x 800.  

I'm done.   Have a good day. 

[Legend]

23 minutes ago, Highmark said:

Legend in your own mind is an accurate phrase for you.

My first Mountain sled was a 2002 Doo Highmark x 800.  

I'm done.   Have a good day. 

You as well.

[SVT MXZ XRS]

6 hours ago, Kev144 said:

Fucking larue was a legend in his own mind.

Guys a fruit loop

 

Whats been going on with you, faggot?

[Boered]

On ‎2016‎-‎09‎-‎13 at 4:17 PM, f7ben said:

actually the majority of the content of that post was very relevant to Crushers claim that belt thickness indeed changes the ratio ....Crusher was wrong

Convolute or involute drivers make no difference in final ratio. On that he is wrong. Where the driver makes contact with the inside of the track is all that is measured.

[f7ben]

Just now, Boered said:

Convolute or involute drivers make no difference in final ratio. On that he is wrong. Where the driver makes contact with the inside of the track is all that is measured.

agree

[Highmark]

2 hours ago, Boered said:

Convolute or involute drivers make no difference in final ratio. On that he is wrong. Where the driver makes contact with the inside of the track is all that is measured.

 

2 hours ago, f7ben said:

agree

Maybe I'm not getting my point or his point across correctly.  Have an open mind and read what I have to say.

Keep in mind I am NOT debating or saying track thickness changes ratio, I'm simply saying how some sprocket companies calculate it can lead to slightly different sprocket diameters or in turn sprocket circumference and sprocket circumference is a variable in final drive ratio.   Albeit small they are different.  The standard formula would be pitch x No. of teeth/ Pi = Sprocket Diameter.   But first how is the track pitch measured to begin with, distance between the lugs when the track is flat (linear pitch like a rack) or curved around the sprocket (curved pitch or pitch diameter)?  Ask yourself what happens to the teeth of a track as it bends around the sprocket and where its being driven?   The tips get closer together.   Look at the picture and visualize the "track" straight and the teeth move apart at their tips equalizing the distance at the pitch diameter.   Some are made to the pitch diameter some less or in between to accommodate and fit the drive locations better pending where they are actually in contact with the track. 

Why do some do it different?   I suppose some feel certain ways its calculated lead to a smoother drive system or better "meshing" of the teeth to track lugs/clips.   My opinion is the mfg choose the larger, tighter fit to let them "wear in" so to speak.   If they perfectly mesh to begin with as the plastic wears you may get some slop.  Stock drivers always seem "tight" to me.   Keep in mind the track has some flex so it can accommodate a less than perfect fit.  Combo drivers have more drive surface and can probably be made to a more perfect fit as they would wear less.

Here are a few posts (Highlighted) from another website that may help showing some sprockets end up with a different diameter..   The avid website even claims some of theirs are smaller diameter with the same number of teeth.   Essentially their pitch is slightly different from how others are measuring them.

Standard calculation for 3" pitch 7 tooth driver would be 6.68" diameter or 21" circumference.  Wahl's is 6.55" and Avid's is 6.25"   Reality is neither of the versions below are exactly 3" pitch using the formula above and even from Wahl's own website calculator.

6.55 x 3.1416 = 20.577 / 7 = 2.94 pitch (Wahl)

6.25" x 3.1416 = 19.635 / 7 = 2.805 pitch (Avid)

6.68" x 3.1416 = 20.985 / 7 = 2.998 pitch (Standard Calculations)

Subtle differences dimension wise from what a 7 tooth 3" pitch really is.

A toothed gear must have an integral number of teeth. The circular pitch, therefore, equals the pitch circumference divided by the number of teeth. The diametral pitch is, by definition, the number of teeth divided by the pitch diameter

Wahl molded 3" Pitch 7 tooth = 6.55" OD
AVID CNC'd 3" Pitch 7 tooth = 6.25" OD

And that is NOT OD of the Extrovert teeth, that's down between them 
where the track rides.

Wahl Extroverts, Injection molded

2.52" pitch
7 tooth 5.5" OD
8 tooth 6.25" OD
9 tooth 7.05" OD

2.86" pitch
7 tooth 6.25" OD
8 tooth 7.125" OD

3.0" pitch
7 tooth 6.55" OD
8 tooth 7.5" OD

Now don't get to excited because it gets a bit confusing with the Avid CNC'd drivers you posted.

I switched to a 3 " pitch track last winter and used AVID 3" pitch 7 tooth drivers. They are ONLY 6.25 " in diameter while molded are 6.55" OD. 

I called them after receiving them but only got to talk to the machinist, not 
the owner of AVID. If I remember right they say theirs are correct. Only thing I can figure is they figure the diameter based on the thickness of the track, either the middle or the outside (track thickness), while molded are using the inside of the track to figure the diameter.

 http://avid-products.com/

http://wahlracing.com/No_Slip_Drive_Sprocket_Application_Chart.pdf

 

 

 

 

Edited September 14, 2016 by Highmark

[Boered]

17 minutes ago, Highmark said:

 

Maybe I'm not getting my point or his point across correctly.  Have an open mind and read what I have to say.

Keep in mind I am NOT debating or saying track thickness changes ratio, I'm simply saying how some sprocket companies calculate it can lead to slightly different sprocket diameters or in turn sprocket circumference and sprocket circumference is a variable in final drive ratio.   Albeit small they are different.  The standard formula would be pitch x No. of teeth/ Pi = Sprocket Diameter.   But first how is the track pitch measured to begin with, distance between the lugs when the track is flat (linear pitch like a rack) or curved around the sprocket (curved pitch or pitch diameter)?  Ask yourself what happens to the teeth of a track as it bends around the sprocket and where its being driven?   The tips get closer together.   Look at the picture and visualize the "track" straight and the teeth move apart at their tips equalizing the distance at the pitch diameter.   Some are made to the pitch diameter some less or in between to accommodate and fit the drive locations better pending where they are actually in contact with the track. 

Why do some do it different?   I suppose some feel certain ways its calculated lead to a smoother drive system or better "meshing" of the teeth to track lugs/clips.   My opinion is the mfg choose the larger, tighter fit to let them "wear in" so to speak.   If they perfectly mesh to begin with as the plastic wears you may get some slop.  Stock drivers always seem "tight" to me.   Keep in mind the track has some flex so it can accommodate a less than perfect fit.  Combo drivers have more drive surface and can probably be made to a more perfect fit as they would wear less.

Here are a few posts (Highlighted) from another website that may help showing some sprockets end up with a different diameter..   The avid website even claims some of theirs are smaller diameter with the same number of teeth.   Essentially their pitch is slightly different from how others are measuring them.

Standard calculation for 3" pitch 7 tooth driver would be 6.68" diameter or 21" circumference.  Wahl's is 6.55" and Avid's is 6.25"   Reality is neither of the versions below are exactly 3" pitch using the formula above and even from Wahl's own website calculator.

6.55 x 3.1416 = 20.577 / 7 = 2.94 pitch (Wahl)

6.25" x 3.1416 = 19.635 / 7 = 2.805 pitch (Avid)

6.68" x 3.1416 = 20.985 / 7 = 2.998 pitch (Standard Calculations)

Subtle differences dimension wise from what a 7 tooth 3" pitch really is.

A toothed gear must have an integral number of teeth. The circular pitch, therefore, equals the pitch circumference divided by the number of teeth. The diametral pitch is, by definition, the number of teeth divided by the pitch diameter

Wahl molded 3" Pitch 7 tooth = 6.55" OD
AVID CNC'd 3" Pitch 7 tooth = 6.25" OD

And that is NOT OD of the Extrovert teeth, that's down between them 
where the track rides.

Wahl Extroverts, Injection molded

2.52" pitch
7 tooth 5.5" OD
8 tooth 6.25" OD
9 tooth 7.05" OD

2.86" pitch
7 tooth 6.25" OD
8 tooth 7.125" OD

3.0" pitch
7 tooth 6.55" OD
8 tooth 7.5" OD

Now don't get to excited because it gets a bit confusing with the Avid CNC'd drivers you posted.

I switched to a 3 " pitch track last winter and used AVID 3" pitch 7 tooth drivers. They are ONLY 6.25 " in diameter while molded are 6.55" OD. 

I called them after receiving them but only got to talk to the machinist, not 
the owner of AVID. If I remember right they say theirs are correct. Only thing I can figure is they figure the diameter based on the thickness of the track, either the middle or the outside (track thickness), while molded are using the inside of the track to figure the diameter.

 http://avid-products.com/

http://wahlracing.com/No_Slip_Drive_Sprocket_Application_Chart.pdf

 

 

 

 

There is no need to consider pitch in an accurate equation. Simply knowing the circumference of the driver using the diameter from the point where it contacts the inside of the track is all you need to do, so it matters not how pitch is measured when doing calculations, there is only one correct answer and it is always found using driver circumference.

[Highmark]

17 hours ago, Boered said:

There is no need to consider pitch in an accurate equation. Simply knowing the circumference of the driver using the diameter from the point where it contacts the inside of the track is all you need to do, so it matters not how pitch is measured when doing calculations, there is only one correct answer and it is always found using driver circumference.

Huh, to be completely accurate you need to know the pitch or the sprocket cannot be made correctly to begin with!    Not the point i was making however in the following examples of contact point or drive point (red and yellow) which has a larger circumference?  Red or yellow?

Gear and timing belt ratio calculators generally take assumptions of a property made gear (sprocket) and just look at number of teeth v. number of teeth or .  Same goes with snowmobile drive sprockets but obviously some mfg's do it differently.  

Its not all that unlike a v-belt.   You cannot calculate ratio without correctly knowing pitch diameter.  You cannot look at simply the OD of the pulleys you have to look at the drive point or pitch diameter.  

How they calculate the pitch diameter of any driver does depend on what PITCH they are using.     

Maybe this will help.

http://file.lasersaur.com/docs-thirdparty/The_World_of_Timing_Belts.pdf

The tooth profile of most commonly known synchronous belts is of trapezoidal shape with sides being straight lines which generate an involute, similar to that of a spur gear tooth. As a result, the profile of the pulley teeth is involute. Unlike the spur gear, however, the outside diameter of a timing pulley is smaller than its pitch diameter, thus creating an imaginary pitch diameter which is larger than the pulley itself

http://www.engineeringtoolbox.com/length-belt-fans-motors-d_872.html

d = Pitch Diameter

Belt Velocity

The velocity at which a belt travels may be expressed as

v = π d_m n_m / 12                 (2)

where

v = velocity of belt (ft/min)

n_m = revolutions motor (rpm)

 In the end if the pitch diameter is constant so is the final drive ratio.   My point and the Polaris engineer point was calculating "circumference" on all drivers is not as simple as taking a tape measure to the surface the track rides on the sprocket and multiplying by 3.1416.    

 

Edited September 15, 2016 by Highmark

[Kev144]

19 hours ago, SVT Renegade XRS said:

Guys a fruit loop

 

Whats been going on with you, faggot?

Just fag things....lol kidding aside work and play keeping me busy.  Hopefully we get a nice winter!  What about you ass captain?

[Momorider]

11 minutes ago, Kev144 said:

Just fag things....lol kidding aside work and play keeping me busy.  Hopefully we get a nice winter!  What about you ass captain?

Yah no shit admitted Faggot 

[Kev144]

1 hour ago, Momorider said:

Yah no shit admitted Faggot 

Settle down butter bean I know you're excited.  

[Momorider]

11 minutes ago, Kev144 said:

Settle down butter bean I know you're excited.  

But in your case it's what you are