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I knew it was only a matter of time before I found a thread in this vein.
My plans now include a 12t and leaving the rear sprocket as is for the time being.

So, in order to roughly calculate individual gear speeds we multiply the circumference of the tire by the engine speed and divide by the combined gear ratio.

Now, the 700 has a reduction gear before the sprockets as I understand.

I multiply the reduction ratio to the individual ratio and then to the primary & secondary sprocket ratio to achieve the combined gear ratio?

I wish to know the speed of XX in the various gears in a stock configuration and be able to compute different, 12t in the first case, ratios and compare them before spending money.

If I figure it out before I receive an answer I'll post the results.

Would seem to me that a calculating program would be available online.

(Probably is and probably wouldn't have an entry for the sub-tranny)

I'm not thinking real clear this morning, have to pay some bills and the reduction gearing might throw me off.

I'm thinking offhand that the sum of the individual gear X the reduction gear X the sum of the two sprockets would equal the combined gear ratio.
 

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Well, I found this calculator.

http://www.ljsoftware.com/DS/GearSpeedCalculator.html

Primary reduction 2.027 (75 X 37)EDIT:(75/37)
final reduction-0.378 (14 X 37)EDIT:(14/37)
sub-tranny-1.087 (25/26 X 26/23)
gear ratio
1st-3.166 (38/12)
2nd--2.187 (35 X 16)EDIT(35/16)
3rd-1.631 (31/19)
4th-1.272 (28/22)
5th-1.040 (26/25)
reverse-2.750 (33/21 X 21/12)
----------------------------
On the primary gear ratio I took the PGR X sub-tranny ratio ending up w/2.203

--------------------
2.203 12/37 22" tyre @
RPM-5K---2K***2K 14/37--5K--6500
MPH
1-16.31-----6.5****7.6----19--24
2-23.24-----9.2****10.8---27--35
3-31.16-----12.4***14.5---36--47
4-39.96-----15.98**18.6---46--60
5-48.87-----19.55**22.8---57--74
R--18.4-----7.39***
-----
19, 27, 36, 46, 57 & 21 in reverse(14/37 @ 5K)
6500 RPM in 5th comes up 74 MPH.

I know this isn't an exact science, but do these figures appear as if they're somewhere in the ballpark?

I read where folks are getting 75 MPH out of the box.

Are you getting 6500 RPM, running stock, in 5th?
----------------------
Not sure what the dealio is, but if you change the value in the Primary Gear Ratio box it doesn't change the MPH.
----------------------------
So, the dif being 1.087 reduction then maybe the MPH X
0.913-EDIT:( I think this should be MPH/1.087 = 68.997. I'm not smart enough to know why the 75/ doesn't add up exactly to 75X, but it's close enough for goobermint work.)
Now, 75 MPH X 0.913 = 68.475
If that's the case then 14/37 @ 7000 RPM in 5th comes to
79.83074254625978 X 0.913 = 72.8854
Seems 8750 RPM is the rev limiter, yet that doesn't tell
me what a box stock will turn in 5th gear.
7500-85.53 X .913 = 78.08 MPH
---------------
No big whoop & I know the XX doesn't come w/tach, but thought I'd ask.

I'm trying to find a reasonable baseline to work from that includes RPM & speed.

I don't figure anyone is bumping the rev limit in 5th.

Anywho, I'm just researching a bit before I get off my wallet.
 

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Well, I found this calculator.

http://www.ljsoftware.com/DS/GearSpeedCalculator.html

Primary reduction 2.027 (75 X 37)
final reduction-0.378 (14 X 37)
sub-tranny-1.087 (25/26 X 26/23)
gear ratio
1st-3.166 (38/12)
2nd--2.187 (35 X 16)
3rd-1.631 (31/19)
4th-1.272 (28/22)
5th-1.040 (26/25)
reverse-2.750 (33/21 X 21/12)
----------------------------
On the primary gear ratio I took the PGR X sub-tranny ratio ending up w/2.203

--------------------
2.203 12/37 22" tyre @
RPM-5K---2K***2K 14/37--5K--6500
MPH
1-16.31-----6.5****7.6----19--24
2-23.24-----9.2****10.8---27--35
3-31.16-----12.4***14.5---36--47
4-39.96-----15.98**18.6---46--60
5-48.87-----19.55**22.8---57--74
R--18.4-----7.39***
-----
19, 27, 36, 46, 57 & 21 in reverse(14/37 @ 5K)
6500 RPM in 5th comes up 74 MPH.

I know this isn't an exact science, but do these figures appear as if they're somewhere in the ballpark?

I read where folks are getting 75 MPH out of the box.

Are you getting 6500 RPM, running stock, in 5th?
----------------------
Not sure what the dealio is, but if you change the value in the Primary Gear Ratio box it doesn't change the MPH.
----------------------------
So, the dif being 1.087 reduction then maybe the MPH X
0.913
Now, 75 MPH X 0.913 = 68.475
If that's the case then 14/37 @ 7000 RPM in 5th comes to
79.83074254625978 X 0.913 = 72.8854
Seems 8750 RPM is the rev limiter, yet that doesn't tell
me what a box stock will turn in 5th gear.
7500-85.53 X .913 = 78.08 MPH
---------------
No big whoop & I know the XX doesn't come w/tach, but thought I'd ask.

I'm trying to find a reasonable baseline to work from that includes RPM & speed.

I don't figure anyone is bumping the rev limit in 5th.

Anywho, I'm just researching a bit before I get off my wallet.
When I dyno'd I hit a limiter at 87mph, Not sure if it was the rev limiter or speed limited dis abler.
 

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I'd guess you hit a rev limiter. The reverse is the only speed limiter I've ever heard of save a mechanical governor and they all, to my knowledge, operate on RPM and then we convert that to a MPH.

Anywho, I'm no whiz, especially on gears, but I think I have the model figured out to the point where it's close.

I figured R-5th w/reduction gear and enter those numbers in the gear ratio model program from them fine folks @ that website.

Primary reduction 2.027 (75/37)
final reduction-0.378 (14/37)
sub-tranny-1.087 (25/26 X 26/23)
gear ratio------- X 1.087
1st-3.166 (38/12)--- 3.441
2nd-2.187 (35 X 16)- 2.377
3rd-1.631 (31/19)--- 1.772
4th-1.272 (28/22)--- 1.382
5th-1.040 (26/25)--- 1.130
reverse-2.750 (33/21 X 21/12)-2.989

This shows 91.84 MPH @ 8750 RPM in 5th.

No factors are alloted for the drag of the tires or the rider and quad, yet for my limited knowledge this appears to be close enough.

If the rev limiter is 8750 and you could peg it in 5th then you would be somewhere around there w/factory gearing and 22" back tyres.

BTW, I ain't proud fellers. If ya see a mistake on any of my posts feel free to jump in and point it out.
 
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