105 Chainrings 2009 Vintage

symo

I have a Kiron Scandium, and need to replace the inner and outer chainrings. It is a Compact 50-30 combo on the chainrings. Anyone know which number chainring this is (ie is it 5700, 5750 or what?).

Anyone know where I can get these el cheapieo?

Tak

Mr Plum

Sorry in advance if I'm teaching you to suck eggs...

5750 is the model number for the compact chainset in the 5700 series of 105 (the new 105, as opposed to the 'old' 5600 series). Chainrings are defined by the number of teeth, so you need a 50t 5700 series chainring and and 30t 5700 series chainring. Sounds like you've got a triple though, as compact is usually 50-34 and a triple is usually 50-39-30?

Either way, if you google "5700 chainring 50t" and "5700 chainring 30t" you'll find what you're looking for, probably not cheap though.

symo

It was indeed a 50 - 34.
Anyone know where to get good cheap replacements?

symo

What I should have asked was; are 5750 and 5650 rings interchangeable?

nicklouse

in most cases any chain ring with the correct BCD will fit (or can be made to fit) some times the shoulder of the ring that rests on the cranks spider is slightly different and requires aplication of a file. This can happen between makes of ring and even some times model . More of an issue with MTB rings and cranks than road ones.

symo

Ordered an Ultegra 6650 inner 34T and a 5650 50T, mainly as that was the cheapest combo. Both have the compact 110bcd sizing so should fit.

symo

Anyone know what tools I will need; for example will I have to remove the crank arms (necessitating in a tool purchase for hollowtech II bb removal, or can I just take the chain off and unbolt the rings in-situ?

Mr Plum

symo wrote:

Anyone know what tools I will need; for example will I have to remove the crank arms (necessitating in a tool purchase for hollowtech II bb removal, or can I just take the chain off and unbolt the rings in-situ?

You'll need to remove the crank arms/chainset completely. You won't need to remove the bottom bracket but it's always handy to have a Hollowtech II tool though. You'll have to unscrew the plastic cap on the non-drive side as well as the allen key bolts from the non-drive side crank arm. The plastic cap is a specific shape - you can actually unscrew it without the special tool but it will make it a lot easier if you had it. You should be able to work the arm loose then and slide the crank out from the drive side.

FYI - I've got this - http://www.ebay.co.uk/itm/ICE-TOOLZ-SHI ... 3cc2c93ae2 - and it's great. I use it with a very long arm 8mm allen key and it works very well. The other side is the shape for the plastic cap which will easily unscrew without the need for an allen key.

gosport_commuter

I haven't dealt with a shimano set, only my FSA chainset, but I would have thought you would be able to leave the chainset on, unbolt the rings, and fit in situ - as I did with my FSA. I see no reason why you wouldn't be able to!

symo

Didn't have to remove the crank at all, just unbolted the chainrings slipped them over the crank arm and then used the chance to clean under the crank arm spider. Then rethreaded the inner on, then and then the outer, and used a bit of copper slip when putting the chainring bolts back on.

Simples.