Sprocket Diameters

[salty_monk]

Anyone have the formula to work out how much difference a 43 tooth sprocket makes over a 42 tooth sprocket as far as chain length is concerned.

This is 520 but pitch is the same as a 530 I believe.

What I'm trying to work out is how much further forward in the adjusters I'd have to run the wheel using the same length chain 114 links & a 16 tooth front sprocket.

If a 43 means running 5mm or similar further forward it would probably benefit me although it would also make the bike a wheelie machine I'm sure...

The diameter of the 43 tooth sprocket would be a start if anyone has that... if anyone has an old 43 tooth 520 that I can use to compare that would also be excellent!

Is this correct? http://www.azusaeng.com/Sprockets/AzSDno50.pdf - I know it's a Kart site but it should be the same whatever as the pitch is a constant.

Dan

[trippivot]

520 and 530 are the same width plate to plate HOWEVER the pin to pin lengths are different (pitch?)

on a 630 chain -same pin to pin length as a 530 only wider

1 tooth is 1.5 turns of the adjuster bolt approx. (maybe only 8 flats not 9)

depends on the tight spot (wear) of your chain.

[salty_monk]

ok that's good info I can work with that... using that link & "pie*D" (i.e. 3.14 x diameter) I can see it's around 16mm based on outside dia, a bit less for inside & then divide by 2 as it's a loop so I reckon it agrees with you, about 5-6mm further forward in the adjuster.

Does it have a similar effect going up or down a tooth on the front?

Billy Ricks or others with 750ES - if you happen to pass by this way... have you tried a 16-43 combination on the 750 with the GSXR wheel? I know you recommended 16-42 & I can get that to work but 16- 43 May just work a bit better for me. I guess I could go 17 - 42 or 17 - 43, that might work too.

Dan

[trippivot]

front sprocket seems to be a 3-1 ratio so maybe 4-5 full turns of the adjusters

maybe 15mm wheel base variance or maybe even a half link difference in chain length (it is going to get too short/long) I am not positive but that is close.


have 2 master links in my chain and a half link in the tool box for at track gear adjustments.

my 630 ratios are
14/47=(3.357-1)
15/51=(3.400-1)
14/48=(3.428-1)
14/49=(3.500-1)
14/50=(3.571-1)

[GregT]

Get it right - in 520 and 530 chain sizing the 5 refers to the pitch - pin to pin length. in this case 5/8inch.
The second digit is the chain roller width again in 1/8in increments
520 being 1/4 in wide, 530 being 3/8 in wide.
525 is 5/8 pitch by 2.5 eighths wide or 5/16 in.

630 on the other hand is an orphan mongrel size - 5/8 in pitch and 3/8 in wide but with bigger roller diameter than 530.So 530 and 630 are not intermixable.

My ex business partner sold more motorcycle chain than anyone else in NZ for years and I've cut bulk rolls till I'm sick of it.

We used to reckon one tooth difference on the front or rear sprocket roughly equaled half the chain pitch in terms of adjustment.

Greg T

[Nessism]

520 and 530 are the same width plate to plate HOWEVER the pin to pin lengths are different (pitch?)

on a 630 chain -same pin to pin length as a 530 only wider

1 tooth is 1.5 turns of the adjuster bolt approx. (maybe only 8 flats not 9)

depends on the tight spot (wear) of your chain.

EDIT: Sorry, didn't notice GregT's post until I typed this. Sorry to repeat the same info...

630 and 530 are the same width, 3/8" wide (that's where the 3 comes from). 520 is 2/8" wide (1/4"). Regarding length between pins, 630 is longer (6/8" or 3/4") so the chain has less links. 520 and 530 (5/8") have the same pitch.