Can the Chainrings be replaced on Shimano Alivio

[npn]

I've got an older Shimano Alivio FC-MC18 Crankset with steel chainrings and I was wondering if I can replace them with aluminum compatible version.

Which set would be compatible? Or how do I go about compatibility?

This is part of my Marin Palisades Trail project http://www.retrobike.co.uk/forum/viewto ... p;t=356050 and I wanted to keep the retro look of the crankset, but replace the rings with something lighter.

 

[legrandefromage]

Yes. Just about any rings can be fitted as long as they are 94 bcd 4 bolt. Spacer washers may be required to keep widths correct if you end up with narrower rings.

 

[npn]

Yes. Just about any rings can be fitted as long as they are 94 bcd 4 bolt. Spacer washers may be required to keep widths correct if you end up with narrower rings.

Something doesn't seem right. I can't find any Shimano chainrigs on ebay that are 94bcd 4 bolt. Could it be another bcd?

 

[legrandefromage]

sorry! its 104mm bcd!

They dont have to be shimano either

https://www.sjscycles.co.uk/104-bcd-4-arm/

http://www.ebay.co.uk/sch/i.html?_from= ... ngs&_sop=2

 

[npn]

Yes. Thank you.

 

[npn]

Realistically, how many grams would I save by replacing the big ring with aluminum version?

For some reason, I can justify the price.

 

[xerxes]

Re:

Realistically, how many grams would I save by replacing the big ring with aluminum version?

Not much, maybe a 100 grams or so, nothing you'd notice without an accurate set of scales, you certainly wouldn't notice it from the saddle, and aluminium rings don't last as long as steel ones.

You probably can't notice much by riding a bike until you get into 1 or 2 pound differences. Also, where the weight is or isn't has an effect, lighter wheels and tyres will likely have more effect on the way a bike feels than the frame or the other components.

Also, unless you're stick thin with 5% body fat, there are far greater and more beneficial savings to be made closer to home.

Lose a stone in weight and you've lost the equivalent of a whole bicycle, albeit a very lightweight one.

 

[jimo746]

Realistically, how many grams would I save by replacing the big ring with aluminum version?

For some reason, I can justify the price.

If you can justify the cost to put an alloy chainring on an Alivio chainset, then you can justify the cost of replacing the chainset for something lighter altogether (if the rings are toast anyway then now is a good time to upgrade).

 

[npn]

I picked FC-M660 http://www.mtbr.com/cat/drivetrain/cran ... 15crx.aspx

The rings only... I wanted to keep the original crankarms of the bike for the retro look. I've upgraded a lot of parts on this bike, in fact, only the seatpost, stem and the crankarms would be the original.

The whole "upgrade" think doesn't make sense financially, but it's something I enjoy doing plus I'll have one of a kind bike.

 

[Titiritero]

Re:

I've got an older Shimano Alivio FC-MC18 Crankset with steel chainrings and I was wondering if I can replace them with aluminum compatible version.

Funny. I usually do the opposite conversion. As some have mentioned, the weight difference is minimal, but the longevity of aluminium rings, from own experience, could be from 1/3 to 1/5 of that from steel rings. I've bought bikes from the early 90's with those cheap one piece steel cranks (shimano 200 GS, Altus, etc.) and usually I only need to replace worn out chain and cassette, but the crankset is still doing great.

I recently bought a new Alivio crankset for my touring bike for the main reason that the chainrings were steel.

In my opinion, wearables (chainrings, cassette, chain, etc.) in aluminium make no sense given the very inverse correlation between lightness and durability, at least for non-competitive level (that is, when you need to pay for them yourself!).