12T to 11T cog?
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12T to 11T cog?
I've been thinking of swapping the first position 12 tooth cog on my 105 10-speed cassette with an 11 tooth one. Is there a certain model I should look for? I can't seem to find one specifically for the 105.
Thanks
Thanks
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I find eBay to be a good source.
https://www.ebay.com/itm/Shimano-10-...sAAOSwKtlWm8ZB
And don't forget the lockring...
https://www.ebay.com/itm/Shimano-XT-M8000-11-Speed-Cassette-Lockring-for-11t-Cog/402510777175?epid=1265996529&hash=item5db7830b57:geYAAOSwZYFfk08z
Or just buy a new 11-XX 10 speed cassette, as noted above, for a little more.
John
https://www.ebay.com/itm/Shimano-10-...sAAOSwKtlWm8ZB
And don't forget the lockring...
https://www.ebay.com/itm/Shimano-XT-M8000-11-Speed-Cassette-Lockring-for-11t-Cog/402510777175?epid=1265996529&hash=item5db7830b57:geYAAOSwZYFfk08z
Or just buy a new 11-XX 10 speed cassette, as noted above, for a little more.
John
Last edited by 70sSanO; 10-25-20 at 11:01 PM.
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I find eBay to be a good source.
https://www.ebay.com/itm/Shimano-10-...sAAOSwKtlWm8ZB
And don't forget the lockring...
https://www.ebay.com/itm/Shimano-XT-M8000-11-Speed-Cassette-Lockring-for-11t-Cog/402510777175?epid=1265996529&hash=item5db7830b57:geYAAOSwZYFfk08z
Or just buy a new 11-XX 10 speed cassette, as noted above, for a little more.
John
https://www.ebay.com/itm/Shimano-10-...sAAOSwKtlWm8ZB
And don't forget the lockring...
https://www.ebay.com/itm/Shimano-XT-M8000-11-Speed-Cassette-Lockring-for-11t-Cog/402510777175?epid=1265996529&hash=item5db7830b57:geYAAOSwZYFfk08z
Or just buy a new 11-XX 10 speed cassette, as noted above, for a little more.
John
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You could swap the 12T cog with an 11T cog but there are two technical considerations. First, I assume your current 2nd position cog is 13T, so going to an 11T 1st position cog will mean you have a LARGE step between the 1st and 2nd cogs (its 8% now, would be 18% after the swap). Second, Shimano designs their cogs to be matched with the adjoining cogs to optimize shifting; meaning if you change to an 11T cog, the shift to the 13T cog (and visa versa) wont be very smooth.
You can buy loose 1st position 10 speed cogs from many vendors. For instance Universal Cycles sells loose 10 speed cogs, see https://www.universalcycles.com/shop...&category=1569. The parts list for Shimano 105 Cassette 10 speed cassettes (CS-5600) can be found at https://si.shimano.com/api/publish/s...5600-2455C.pdf.
You can buy loose 1st position 10 speed cogs from many vendors. For instance Universal Cycles sells loose 10 speed cogs, see https://www.universalcycles.com/shop...&category=1569. The parts list for Shimano 105 Cassette 10 speed cassettes (CS-5600) can be found at https://si.shimano.com/api/publish/s...5600-2455C.pdf.
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I checked 11t and 12t Sunrace lockrings and the 11t is smaller.
One more thing I just remembered. At one time there used to be a difference in ramps between 1t difference and 2t difference cogs. I once did a 1st & 2nd position cog swap, 13/15 to 12/14. The problem on the 14t cog was it only had one ramp. It seemed to hesitate when shifting. The 2 tooth change cog had 2 ramps. I have no clue if that is still done or not, but I thought I would mention it.
John
One more thing I just remembered. At one time there used to be a difference in ramps between 1t difference and 2t difference cogs. I once did a 1st & 2nd position cog swap, 13/15 to 12/14. The problem on the 14t cog was it only had one ramp. It seemed to hesitate when shifting. The 2 tooth change cog had 2 ramps. I have no clue if that is still done or not, but I thought I would mention it.
John
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Another issue with replacing a 12T with 11T is that many of the 11T cogs have a built-in spacer that is that is thicker than the normal amount needed to properly space the cogs. The added thickness is added to strengthen the cog since the 11T cog's "valley" in the gear is so close to the center of the cog. Because of the added thickness in the 11T cog, the matching 2nd cog (usually 12T or 13T) has a recessed area to take up the additional amount while maintaining proper spacing.
Note the recessed area in the pic.
A 13T second position cog that is meant for a 12T first position may not have the recessed area since it is not needed. The 12T first position cog would be just thick enough to maintain proper spacing since it doesn't need the added strength needed in the 11T cog.
So, a 11T cog, with the added thickness, used with a 13T second position cog without the recessed area will sit further out & not have the proper spacing.
Note the recessed area in the pic.
A 13T second position cog that is meant for a 12T first position may not have the recessed area since it is not needed. The 12T first position cog would be just thick enough to maintain proper spacing since it doesn't need the added strength needed in the 11T cog.
So, a 11T cog, with the added thickness, used with a 13T second position cog without the recessed area will sit further out & not have the proper spacing.
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You're going to need a new cassette eventually. Just buy a new 11-28 cassette for $40 and avoid the hassle.
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Took the advice, went to ebay and bought a used 11-25 105 Cassette.
I swapped out the last three rings/spider with my 12-27 so now I have a 11-27 cassette
It works great and I love the extra range
Thanks everyone for the great advice - much appreciated
I swapped out the last three rings/spider with my 12-27 so now I have a 11-27 cassette
It works great and I love the extra range
Thanks everyone for the great advice - much appreciated
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Found a used dura ace 11-28 for cheap. Omg it’s light and shifts even nicer. Plus the 28 coupled with my triple’s 30 chainring means if I can’t climb it I’m not trying
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