New cassette with new chain?

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Comments

  • wildmoustache
    wildmoustache Posts: 4,010
    dennisn wrote:
    I don't subscribe to the theory of new chain - new cassette. The idea seems to be
    pushed more by bike part marketers than any real evidence that it's necessary.
    I don't do it and have not had problems.

    Dennis Noward

    I used to think differently and fall for it, but now agree with you dennis.

    Buy one ... see if it works, if not buy the other ...

    Most of the time changing one will work
  • dennisn
    dennisn Posts: 10,601
    wildmoustache wrote:
    dennisn wrote:
    I don't subscribe to the theory of new chain - new cassette. The idea seems to be
    pushed more by bike part marketers than any real evidence that it's necessary.
    I don't do it and have not had problems.

    Dennis Noward

    I used to think differently and fall for it, but now agree with you dennis.

    Buy one ... see if it works, if not buy the other ...

    Most of the time changing one will work

    I used to buy the fancy lightweight cassettes when I was doing a bit of racing but now
    I figure why spend all that money for something that wears out so quick. I go with steel
    cogs. Cheaper and seem to last longer. Sort of asking myself "what the hell was I thinking back then?".

    Dennis Noward
  • peanut
    peanut Posts: 1,373
    very nice pictures Wil
    I think I can see your problem but it is difficult to see the bit I need clearly.
    It looks to me that the front face of your front mech is not precisely parallel with the big chainring.
    It looks from the images as though the cage is kicking out at the back

    Can you lift the chain off the chainrings at the front then adjust the front mech so that the front plate of the front mech is exactly above the teeth of the big chainring . Check that the cage front plate is exactly in line with the chainring teeth
  • Ken Night
    Ken Night Posts: 2,005
    Is the front mech from an older groupset-looks to be a "standard" whereas you're using 50/34. Maybe try a compact mech
    “It is by riding a bicycle that you learn the contours of a country best..." Ernest Hemingway
  • peanut
    peanut Posts: 1,373
    Ken Night wrote:
    Is the front mech from an older groupset-looks to be a "standard" whereas you're using 50/34. Maybe try a compact mech
    its a good point Ken but any front mech should work reasonably well.

    This problem has nothing to do with chain suck imo .Chain suck is where the chain doesn't release properly from the underside of the big chainring not the top.
    This issue is almost certainly caused by misalignment of the front mech cage . This might be due to the cage being distorted by the constant chain snagging events on the front rings.

    I would suggest removing the front mech and fitting another one .It needn't necessarily need to be the same range an old 9 speed Mirage would do for testing.Set it up properly and test it. I reckon that would sort the problem permanently.
  • wilwil
    wilwil Posts: 374
    peanut wrote:
    Ken Night wrote:
    Is the front mech from an older groupset-looks to be a "standard" whereas you're using 50/34. Maybe try a compact mech
    its a good point Ken but any front mech should work reasonably well.

    This problem has nothing to do with chain suck imo .Chain suck is where the chain doesn't release properly from the underside of the big chainring not the top.
    This issue is almost certainly caused by misalignment of the front mech cage . This might be due to the cage being distorted by the constant chain snagging events on the front rings.

    I would suggest removing the front mech and fitting another one .It needn't necessarily need to be the same range an old 9 speed Mirage would do for testing.Set it up properly and test it. I reckon that would sort the problem permanently.

    The chain isn't releasing from the underside of the large ring. It comes off at the top fine then sticks at the bottom and all the way round until it overlaps the face plate and jams.
  • wilwil
    wilwil Posts: 374
    Ken Night wrote:
    Is the front mech from an older groupset-looks to be a "standard" whereas you're using 50/34. Maybe try a compact mech
    It is the mech that was on the bike from new. Would Wilier put the wrong mech on?
  • peanut
    peanut Posts: 1,373
    wilwil wrote:
    Ken Night wrote:
    Is the front mech from an older groupset-looks to be a "standard" whereas you're using 50/34. Maybe try a compact mech
    It is the mech that was on the bike from new. Would Wilier put the wrong mech on?

    ok I stand corrected . I understood the chain was having difficulty coming off the top of the chainrings.
    Its so difficult to diagnose when you can't actually see it. :roll:

    Now that you say the chain won't come off of the bottom of the rings it sounds like possibly your rear mech tension spring may not be strong enough ? or possibly the chainrings may not be 10 speed ?

    You haven't answered the important question about front mech cage alignment. This alignment is critical to correct operation and could have been altered if the cage has been distorted or damaged

    Any chance of a couple of picss of your front mech?
    If you remove the screw on the cage you can remove the chain without taking the link out .It will be easier to see the front mech without the chain there
  • Nuggs
    Nuggs Posts: 1,804
    wildmoustache wrote:
    dennisn wrote:
    I don't subscribe to the theory of new chain - new cassette. The idea seems to be
    pushed more by bike part marketers than any real evidence that it's necessary.
    I don't do it and have not had problems.

    Dennis Noward

    I used to think differently and fall for it, but now agree with you dennis.

    Buy one ... see if it works, if not buy the other ...

    Most of the time changing one will work
    It seems the wear-rate of cassettes can be somewhat unpredictable. I was hoping to re-use a cassette with only around 1,000 miles on it - the chain skipped all over the place...
  • Ken Night
    Ken Night Posts: 2,005
    peanut wrote:
    Ken Night wrote:
    Is the front mech from an older groupset-looks to be a "standard" whereas you're using 50/34. Maybe try a compact mech
    its a good point Ken but any front mech should work reasonably well.

    This problem has nothing to do with chain suck imo .Chain suck is where the chain doesn't release properly from the underside of the big chainring not the top.
    This issue is almost certainly caused by misalignment of the front mech cage . This might be due to the cage being distorted by the constant chain snagging events on the front rings.

    I would suggest removing the front mech and fitting another one .It needn't necessarily need to be the same range an old 9 speed Mirage would do for testing.Set it up properly and test it. I reckon that would sort the problem permanently.

    Agreed, modern derailleurs should work, and as Peanut says, its worth trying changing the mech

    A mistake can always be made in the build.....

    If its from the underside, and not on all rear sprockets, it could be your chainline..........I won't explain here-check out Sheldon Brown
    “It is by riding a bicycle that you learn the contours of a country best..." Ernest Hemingway
  • dennisn
    dennisn Posts: 10,601
    Nuggs wrote:
    wildmoustache wrote:
    dennisn wrote:
    I don't subscribe to the theory of new chain - new cassette. The idea seems to be
    pushed more by bike part marketers than any real evidence that it's necessary.
    I don't do it and have not had problems.

    Dennis Noward

    I used to think differently and fall for it, but now agree with you dennis.

    Buy one ... see if it works, if not buy the other ...

    Most of the time changing one will work
    It seems the wear-rate of cassettes can be somewhat unpredictable. I was hoping to re-use a cassette with only around 1,000 miles on it - the chain skipped all over the place...


    Unpredictable wear rate, yes. 1000 miles and wore out?? Maybe, if it's a MTB and you ride through sand every day, don't clean your chain, and don't oil it. 1000 miles, in my experience, is not that bad for a road cassette which has had reasonable cleanings and oilings. I know that doesn't help but I think your problem lies elsewhere. Hard to figure
    without seeing the bike in person.

    Dennis Noward
  • wilwil
    wilwil Posts: 374
    Just an update. I changed the chain and its cured the problem – no more suck. However it's noisy on the lower gears (largest cogs) at the back but doesn't jump. The strange thing is, is that they only became noisy after about 10 miles.
  • John.T
    John.T Posts: 3,698
    Could be indexing is slightly out or 'B' screw adjusted too close to the cogs. Not sure how this is done on Campag but there must be some adjustment there.
    My Fleet.
  • peanut
    peanut Posts: 1,373
    glad to hear its cured it WilWil its good to get some closure on this which might help others . I still think there must have been something wrong with your chain like an overtightened link or seized link to cause that problem. Did you go through the chain and check each link to see if all the links are loose and floppy ?
  • wilwil
    wilwil Posts: 374
    John.T wrote:
    Could be indexing is slightly out or 'B' screw adjusted too close to the cogs. Not sure how this is done on Campag but there must be some adjustment there.

    You could have something there. The cage was very close to the cogs must be that new chain was very slightly shorter. Why it only makes a noise after 10 miles and only when I actually ride the bike, I don't know. I hope I haven't done any damage riding it with not enough clearance.
  • John.T
    John.T Posts: 3,698
    It is usually better to have the chain slightly long rather than short.
    My Fleet.
  • alfablue
    alfablue Posts: 8,497
    wilwil wrote:
    John.T wrote:
    Could be indexing is slightly out or 'B' screw adjusted too close to the cogs. Not sure how this is done on Campag but there must be some adjustment there.

    You could have something there. The cage was very close to the cogs must be that new chain was very slightly shorter. Why it only makes a noise after 10 miles and only when I actually ride the bike, I don't know. I hope I haven't done any damage riding it with not enough clearance.

    I think a longer (not shorter) chain will make it nearer the cogs...you lose tension on the mech and it goes backwards and the jockey wheel gets nearer the sprockets.

    Slightly long rather than slightly short makes sense, however it was my slightly long chain that was causing the jockey wheel to ride over the sprockets on my bike - adjusting the B screw all the way didn't fix it, but one link out of the chain did and I could wind the B screw back a bit. This was quite a revelation to me as I had always assumed the opposite would be the case!
  • John.T
    John.T Posts: 3,698
    A longer chain causes the lower pivot to move back and down. This lowers the jockey cage but can make the top jockey raise a little. You need to find a compromise as the geometry is quite complicated. I always go for the manufacturers correct setting but if this does not go exactly I ere on the long side. With Shimano 50/34 and 12/27 you are right on the mechs limits so chain length is quite critical.
    My Fleet.
  • alfablue
    alfablue Posts: 8,497
    This is the answer to correct chain length

    rigorous.jpg

    Er, there are other approaches; the Park Tools web site suggests 3 methods; and a fourth is suggested by Shimano, which is that the two jockey wheels should be vertically aligned when the chain is on the smallest sprocket and largest ring.

    Shimano says (short cage mech):

    chain.jpg

    A 5th method is to set the chain so that it just misses the mech cage under the guide wheel when the chain is on smallest sprocket and smallest chainring.

    I set mine using the 5th method and it was also correct by the 4th. I have Shimano Dura Ace mech short cage, 50/34, 12/27. It works perfectly now.
  • John.T
    John.T Posts: 3,698
    I use method 4 with a bias towards 5 if the jockeys are not vertical. With 50/34 and 12/27 the chain is a bit short on big/big if you go the other way. I have 3 bikes running this and all work just fine. I try to avoid the extreme chain lines but have been known to go big/big when I over estimated the legs or under estimated the hill.
    My Fleet.
  • derby
    derby Posts: 114
    Method 5!
  • wilwil
    wilwil Posts: 374
    [quote="alfablue"

    A 5th method is to set the chain so that it just misses the mech cage under the guide wheel when the chain is on smallest sprocket and smallest chainring.

    I set mine using the 5th method and it was also correct by the 4th. I have Shimano Dura Ace mech short cage, 50/34, 12/27. It works perfectly now.[/quote]

    My chain is about 10 mm below the Centaur mech cae. Is that too far? Is it too lose or too tight?
  • wilwil
    wilwil Posts: 374
    [quote="alfablue"

    A 5th method is to set the chain so that it just misses the mech cage under the guide wheel when the chain is on smallest sprocket and smallest chainring.

    I set mine using the 5th method and it was also correct by the 4th. I have Shimano Dura Ace mech short cage, 50/34, 12/27. It works perfectly now.[/quote]

    My chain is about 10 mm below the Centaur mech cae. Is that too far? Is it too lose or too tight?
  • alfablue
    alfablue Posts: 8,497
    I don't know if the above would apply to Campag (though I don't see why not), mine runs about 3mm below. Why not just pinch 2 links together on the lower chain run and see what difference it makes to the proximity of the guide wheel to the cassette on the largest sprocket, and how much clearance you get below the guide pulley cage when on small sprocket/large ring. If your guide pulley rides on the large cassette sprocket then something is wrong though, so chain length and / or B screw (or the Campag equivalent).

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