Replacing chain rings

[whizzzz]

I have an old mountain bike that I use to commute, its done a sterling service, but the chain rings etc are getting very worn.

I think to replace the 3 rings ( an LX crank set ) I need a crank puller tool to remove the crank to then allow me to get the rings off. Is it possible to remove them without removing the crank ( saving me money on a tool I am unlikely to use very often ) ? I think the first ring should be easy, but I am unsure about the middle and inner ?

The offending cranks are below ( please excuse the dirt, its been a wet and dirty few weeks around Hampshire ).

[whizzzz]

LX 3 ring cranks

[Vantage]

The outer and middle rings will just slip off over the ring arms but you'll need to get the whole crankarm off to remove the granny/inner ring.

[NUKe]

It will probably cost more for 3 three rings than it will for a complete new chain set and crank extractor.

However the 2 outer rings are a problem to remove you need an allen Key and something to hold the sleeve on the back of the chainset. but the inside ring may be riveted. look from the other side to that shown in the picture to determine how the inner ring is attached and if can be removed.

Vanatage is probably right though even if it is easy to unbolt the inner ring you may need to remove the crank arm to remove the ring.

[whizzzz]

Thank you both !

I will get two rings ( cassette and chain ) ordered and have a play !

[gregoryoftours]

I think to replace the 3 rings ( an LX crank set ) I need a crank puller tool to remove the crank to then allow me to get the rings off. Is it possible to remove them without removing the crank ( saving me money on a tool I am unlikely to use very often ) ? I think the first ring should be easy, but I am unsure about the middle and inner ?

Is your LX crank a 4 arm model or an older 5 arm version? Does your granny ring need replacing? Quite often they last longer than middle and outer rings as they are often steel. In this case I'd probably just buy middle and outer chainrings, then you won't have to bother buying a crank puller. Otherwise yes you'll need to remove the crank as the small ring won't fit over the spider. If it's all three that need changing then it would probably be cheaper to buy a new chainset, and either transfer the rings or use the new chainset as is, although you're restricted to buying a chainset with same bb type unless you change bb too.

[gregoryoftours]

By the way, Rose bikes is very cheap for sq taper chainset - it's £7 odd quid postage but if you buy a few things it should still be a saving.

[gregoryoftours]

Rings cheap here too - http://www.bike-discount.de/en/shop/9-speed-427

[whizzzz]

Is your LX crank a 4 arm model or an older 5 arm version? Does your granny ring need replacing? Quite often they last longer than middle and outer rings as they are often steel. In this case I'd probably just buy middle and outer chainrings, then you won't have to bother buying a crank puller. Otherwise yes you'll need to remove the crank as the small ring won't fit over the spider. If it's all three that need changing then it would probably be cheaper to buy a new chainset, and either transfer the rings or use the new chainset as is, although you're restricted to buying a chainset with same bb type unless you change bb too.

Thanks that was kind of what I was thinking and hoping, I dont use the granny ring much either, so had hoped it had fared better than the middle and large ones.

The odd bit is that the pic above shows the bits connecting the large ring as not symmetric, where as most of the rings I see are. Going to have to see if a normal one fits it okay, I think it will.

Cheers All !

[gregoryoftours]

The odd bit is that the pic above shows the bits connecting the large ring as not symmetric, where as most of the rings I see are. Going to have to see if a normal one fits it okay, I think it will.

Sorry my interweb doesn't like your picture, it sounds interesting though!

[whizzzz]

Thanks all for the advice.

I swapped the rings over last night ( with new chain and cassette ). With the pedal off, the outer ring was easy to remove, the middle ring was a bit trickier with a little faffing to get it over the crank arms. Getting the new ones on was similar, a little fiddly getting the right angle ( and I had to take off the small ring to get the angles right etc ).

I think I might have got the wrong middle ring as it had some plastic ( http://www.wiggle.co.uk/shimano-fc-m660-black-32t-chainring/ ) which causes issues for the chain dropping to the small ring, but it worked okay for the short commute and will last until I can get a more simple (http://www.wiggle.co.uk/shimano-fc-m410415-silver-32t-chainring/) one which I think was like the one that was on it

Again, thank you !

[Brucey]

the plastic shoulder part is meant to help shifting but it will only do so if the chainrings are appropriately spaced (which they might not be).

FWIW if you are stuck with that chainring, you have little to lose by reshaping (or perhaps even removing) that plastic shoulder part. The 'simpler one' also has shoulders, but they are metal rather than plastic.

cheers

[whizzzz]

FWIW if you are stuck with that chainring, you have little to lose by reshaping (or perhaps even removing) that plastic shoulder part. The 'simpler one' also has shoulders, but they are metal rather than plastic.

cheers

Good point, I might get my Dremel thingy out

[Brucey]

the other option (if it might work with the inner ring in a different place) is to pack out the inner ring on some washers. Probably simpler to do that in fact.

cheers