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Obvious??

Joined
Feb 21, 2011
Messages
1,350
Location
Austin
First Name
Jeff
I have two wheel sets for my Versys, with two different tooth-count rear sprockets, difference of 3 teeth I think. One chain is just fine for both, given how much wheel adjustment it's got.
 
Joined
Aug 15, 2006
Messages
8,332
Location
Huntsville
First Name
Rob
Last Name
Vaughan
Got everything in, went with 52 and 116. Just need time and energy, lol.
 

StromXTc

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Joined
Dec 29, 2017
Messages
3,208
Location
George West
First Name
Brian
Check my math. I think it is 1 extra link for two teeth.

Assuming that the chain leaves the gear at the halfway point, which is close but not exact, you get:

Chain length old = 2*L + (2*pi*r1)/2 + (2*pi*r2)/2

Where L is the distance between sprockets r1 is the radius of the front sprocket and r2 is the radius of the second sprocket. (2*pi*r) is the circumference of the sprocket, but the chain only travels half of the sprocket so (2*pi*r).

So if you add two teeth, to the sprocket the circumference is 2*pi*r+2x. where x is a link length.

My new equation with the new rear sprocket, keeping the sprocket adjuster in place (the length between the sprockets is constant) is then

Chain Length new = 2*L + (2*pi*r1)/2 + (2*pi*r2 + 2x)/2
Which is
Chain Length New = 2*L + (2*pi*r1)/2 + (2*pi*r2) + 2x/2

So Chain length New minus chain length old is 2x/2 = x = the length of 1 link. ??

Or intuitively, you can think of one tooth being added to the right of the sprocket, where the chain is, and one tooth being added to the left of the sprocked where the chain ain't...so the chain only has to get one tooth longer...

???View attachment 244415
Did you get that South Tx, :lol2:
 
Joined
Oct 16, 2008
Messages
1,936
Location
Bryan, TX
Diderich is right. If you disregard the slight change of angle due to an increase or decrease in sprocket change, a two tooth change in sprocket size would require an increase of 1 link of chain. A two tooth change of sprocket size will increase wheel base by 5/16" for a 520 or 530 chain, 1/4" for a 420 chain and 3/8 for a 630 chain.
 
Joined
Aug 15, 2006
Messages
8,332
Location
Huntsville
First Name
Rob
Last Name
Vaughan
Switched out today, 116 worked but did have to pull wheel back. The 114 I had might work but wheel would be pretty far forward. Headed to SHNF and see if I like the 52!
 

South Tex

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Joined
Nov 10, 2017
Messages
1,103
Location
Kosciusko
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Kirk
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Shannon
Switched out today, 116 worked but did have to pull wheel back. The 114 I had might work but wheel would be pretty far forward. Headed to SHNF and see if I like the 52!
details and review please. I went to a 13/50 on my fx350 and it’s ok, but could be better
 
Joined
Aug 15, 2006
Messages
8,332
Location
Huntsville
First Name
Rob
Last Name
Vaughan
Stock on the 450 was 13/50, last time I went 13/51, tried the 13/52 this time. Jury still out after only 1 ride but might like the 51 better. I was able to run 2nd and 3rd gear in SHNF, worked well actually, only 1 flameout and it was on me. Maybe in my head but seemed like engine braking was magnified, had to be careful on all those whoops to keep throttle on or front seemed to drop in whoops, not good. Bike seemed lighter, maybe because it was a little more lively revving? I mean don't start I know it's not lighter, lol. SHNF isn't tight anywhere or technical, at Cycleland or Brunes I'll find out if I can stay out of 1st which is one of the goals.
 
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