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Going from a 12-30 to a 13-30 cassette?

dieselgeezerdieselgeezer Posts: 229
edited October 2015 in Workshop
I have a Shimano 10 speed 12-30 cassette (12 13 14 15 17 19 21 24 27 30). I don't need the 12 but definitely would like a 16. I have tried removing the 12 & using the 16 from various other cassettes I have. The problem is a very poor shift from the 16 to the 17. Going 17 to 16 isn't an issue. I know that Shimano cogs have an array of different code numbers even though they look the same to me.
Anyone got any ideas as to how to get this set-up to work?
Many thanks.
-- "I am but a spoke in the wheel of life" -- Ghandi

Posts

  • arlowoodarlowood Posts: 2,527
    Got a couple of 12-30 Tiagra cassettes lying around so I thought i'd have a look to see if I could spot any obvious issues with the swap you are attempting.

    The first thing I've noted is that the 12 tooth cog that you have discarded may be integral to the correct clamping of the cassette onto the freehub.

    Not only does it have a recess machined in it that acts as a spacer between the 12 and 13 cog, it also has a knurled area machined onto its circumference that acts as a "biting" area to allow the lockring to tighten and hold the set of cogs firmly. The 13 cog does not have this and I'm just wondering if the lockring is not being properly effective and preventing the bock of cogs being clamped in the right way.

    Just also checked again and noted that the Tiagra 12-30 only has the 12,13 and 14 as separate cogs. The 15-30 part is a monoblock unit so cannot allow the swapping of individual cogs. I'm guessing you have an Ultegra cassette but it might still be an issue with the 12 cog design.
  • It is an Ultegra so only the 24,27 & 30 are integral. The 13 clamps fine despite the lack of serrations. The code on the 16 from the parts bin IS totally different to the remaining codes even though it looks very similar.
    -- "I am but a spoke in the wheel of life" -- Ghandi
  • arlowoodarlowood Posts: 2,527
    Found an Ultegra 16t sprocket on offer from SJS

    http://www.sjscycles.co.uk/shimano-ultegra-cs-6600-sprocket-16t-1z8-1600-d-prod30243/

    It's a 6600 10-speed but I'm sure it should be OK for later 10-speed incarnations. It should have the correct ramping profile to match the cogs either side and give you the smooth changes you seek
  • AnonymousAnonymous Posts: 79,678
    Am I reading this correctly?

    You have a 12-30 cassette. You removed the 12 cog and stuck a 16 cog in the middle and then put it back on the wheel. Have you got the 13 toothed cog from another cassette in place of the 12 or is the top gear now the previously 2nd top gear?

    If this is the case how is the securing bolt threading into the 13? The cassette would be moving about if this is the case.
  • keef66keef66 Posts: 13,123
    Am I reading this correctly?

    You have a 12-30 cassette. You removed the 12 cog and stuck a 16 cog in the middle and then put it back on the wheel. Have you got the 13 toothed cog from another cassette in place of the 12 or is the top gear now the previously 2nd top gear?

    If this is the case how is the securing bolt threading into the 13? The cassette would be moving about if this is the case.

    Not understanding your question. Securing bolt?? If you mean the lock-ring then that screws into the threads on the inside of the outer end of the freehub body and only presses on the outermost sprocket.

    To the OP: when you stick your 16t sprocket in the middle of the cluster, do the teeth line up like they do with the others? Does the spacing look the same?
  • AnonymousAnonymous Posts: 79,678
    Am I reading this correctly?

    You have a 12-30 cassette. You removed the 12 cog and stuck a 16 cog in the middle and then put it back on the wheel. Have you got the 13 toothed cog from another cassette in place of the 12 or is the top gear now the previously 2nd top gear?

    If this is the case how is the securing bolt threading into the 13? The cassette would be moving about if this is the case.

    Not understanding your question. Securing bolt?? If you mean the lock-ring then that screws into the threads on the inside of the outer end of the freehub body and only presses on the outermost sprocket.

    To the OP: when you stick your 16t sprocket in the middle of the cluster, do the teeth line up like they do with the others? Does the spacing look the same?

    I will rephrase. It sounds to me the 12 cog which the lock-ring (I couln't remeber the name at the time) screws into has been tossed away leaving the next down cog (13 tooth) in its place and the 16 being put in the cassette to keep it 10 speed. If this is the case, Said lock-ring is left to just move about and is doing the square route of FA. This would mean there is a slight gap in the overall width of the cassette since the thread inside the lock ring is not engaging with the missing 12 cog. IF a 13 tooth cog was put in from an actual 13-30 cassette then this would not be a problem but then im sure you would buy one and not be in this situation
  • keef66keef66 Posts: 13,123
    Am I reading this correctly?

    You have a 12-30 cassette. You removed the 12 cog and stuck a 16 cog in the middle and then put it back on the wheel. Have you got the 13 toothed cog from another cassette in place of the 12 or is the top gear now the previously 2nd top gear?

    If this is the case how is the securing bolt threading into the 13? The cassette would be moving about if this is the case.

    Not understanding your question. Securing bolt?? If you mean the lock-ring then that screws into the threads on the inside of the outer end of the freehub body and only presses on the outermost sprocket.

    To the OP: when you stick your 16t sprocket in the middle of the cluster, do the teeth line up like they do with the others? Does the spacing look the same?

    I will rephrase. It sounds to me the 12 cog which the lock-ring (I couln't remeber the name at the time) screws into has been tossed away leaving the next down cog (13 tooth) in its place and the 16 being put in the cassette to keep it 10 speed. If this is the case, Said lock-ring is left to just move about and is doing the square route of FA. This would mean there is a slight gap in the overall width of the cassette since the thread inside the lock ring is not engaging with the missing 12 cog. IF a 13 tooth cog was put in from an actual 13-30 cassette then this would not be a problem but then im sure you would buy one and not be in this situation

    On all my Shimano cassettes and freehubs the lock-rings do not screw into the smallest sprocket but into the threads on the inside of the outboard end of the freehub body. None of the sprockets have threads, but as mentioned above the smallest one does usually have little serrations on it's outer face for the lock-ring to bite against as it is tightened down.
  • AnonymousAnonymous Posts: 79,678
    Am I reading this correctly?

    You have a 12-30 cassette. You removed the 12 cog and stuck a 16 cog in the middle and then put it back on the wheel. Have you got the 13 toothed cog from another cassette in place of the 12 or is the top gear now the previously 2nd top gear?

    If this is the case how is the securing bolt threading into the 13? The cassette would be moving about if this is the case.

    Not understanding your question. Securing bolt?? If you mean the lock-ring then that screws into the threads on the inside of the outer end of the freehub body and only presses on the outermost sprocket.

    To the OP: when you stick your 16t sprocket in the middle of the cluster, do the teeth line up like they do with the others? Does the spacing look the same?

    I will rephrase. It sounds to me the 12 cog which the lock-ring (I couln't remeber the name at the time) screws into has been tossed away leaving the next down cog (13 tooth) in its place and the 16 being put in the cassette to keep it 10 speed. If this is the case, Said lock-ring is left to just move about and is doing the square route of FA. This would mean there is a slight gap in the overall width of the cassette since the thread inside the lock ring is not engaging with the missing 12 cog. IF a 13 tooth cog was put in from an actual 13-30 cassette then this would not be a problem but then im sure you would buy one and not be in this situation

    On all my Shimano cassettes and freehubs the lock-rings do not screw into the smallest sprocket but into the threads on the inside of the outboard end of the freehub body. None of the sprockets have threads, but as mentioned above the smallest one does usually have little serrations on it's outer face for the lock-ring to bite against as it is tightened down.

    Agree about the threading bit. But as you rightly mention needs the smallest cog to complete the whole locking mechanism. Without it the width of the cassette is reduced in the same way some need a 1mm spacer behind them to eleviate the same issue even with the correct cog fitted
  • arlowoodarlowood Posts: 2,527
    The OP has already stated that the lockring appears to clamp effectively onto the 13t sprocket once the original 12t has been removed.

    My guess is that it is more down to a spacer issue, unless he has already addressed that.

    On his original Ultegra 10 speed cassette the cogs are 12,13,14,15,17,19,21,24,27,30. The largest 3 cogs are an integral unit but all the others will have either separate spacers or will be machined with a a spacer built into the shape of the cog itself.

    My guess is that in his original set-up there would be a separate spacer between the 15t and 17t. If he drops the 12t (which will have a spacer built into its shape) and inserts a 16t between the 15 and 17t cogs then he will be a spacer short somewhere along the line.

    Therefore his shifting issues are more likely to be due to proper alignment of the cogs.

    Maybe the OP could confirm if he did indeed put a new spacer between the 15 and 16t cog and include the old spacer between the 16 and 17t cogs when he assembled his hybrid 10-speed.
  • AnonymousAnonymous Posts: 79,678
    I have just looked into recreating this during lunchtime. I have a few cassettes spare off wheels so I attempted to do exactly as the OP has done. In replacing the 12 cog out of the cassette and indeed sticking a 16 tooth in the whole thing does tighten up ok. BUT, the first 2 cogs which interlink are thicker than the remaining loose cogs by about a mm or so. Even as they interlock they are still overall thicker than the width of the 16 thats replacing it.

    So by removing the slightly thicker 12 cog and putting in the thinner 16 cog the cassette 'as a whole' has reduced in width ever so slightly but enough to cause the issues.

    This was done using 2 105 cassettes one a 12-28 and an 11-25
  • Sorry for the delay; just got back from work.
    To clarify, I started with an Ultegra 12-30. Discarded the 12. Added a 16 from an equally used cassette. Used the lockring to clamp down the original 13 (same dims as a 12, just no serrations). Then found the shift from the 16 to the 17 was poor.
    Meanwhile, the CTC forum suggested that I file off the largest castellation from the 16. This allowed me to rotate the 16 on the hub body in about 6 different positions. On the 2nd attempt I found that the indexing works. Apparently all to do with the timing of the adjacent sprockets.
    Sorry not to get back to you all sooner but at least it seems to be a RESULT.
    Thanks for all of your input.
    -- "I am but a spoke in the wheel of life" -- Ghandi
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