Chainset interchangability

[francovendee]

Hi, I'm new here so hope someone has the information I need. I need to change the chainset and wonder if I can just buy a new on and it'll fit? It's a shimano square taper and the bike has an emount (bottom bracket) deraillieur so I've got limited adjustment. I would fit like for likebut the model is no longer available.
Hoping one of you can help

Colin

[squeaker]

Trying to help, but if you don't know, maybe you should go to your local bike shop (it might be worth asking here for recommended shops near you)?
Alternatively, Sheldon Brown's mine of information will help you read up on the technicalities, and Park Tools website will guide you regarding doing the work.
I'd guess, but can't say definitely, that a Shimano square taper crank with the same size chainwheels should get you into the ballpark, but accept no liability if it ends in tears....
HTH (a bit!).

[francovendee]

Many thanks squeeker, I've taken a look at Seldons site but couldn't find exactly the answers to my question. As for a local bike shop, my problem is I live in France and don't have eough French to explain my problem. I think I'll take a flyer on Shimano Tapers being reasonably the same and just order one and give it a try.

[gaz]

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[JEJV]

Hi, I'm new here so hope someone has the information I need. I need to change the chainset

First, why are you trying to change the chainset ?
What is the problem that you are trying to solve ?

and wonder if I can just buy a new on and it'll fit?

It's a shimano square taper and the bike has an emount (bottom bracket) deraillieur so I've got limited adjustment. I would fit like for likebut the model is no longer available.

What is the chainset you have now ?
And front deraillieur ?

Bottom bracket deraillieur usually means mountain bike with rear suspension, a 113mm E-type bottom bracket, or maybe a shorter normal bottom bracket, and what Shimano calls a 50mm chainline for the front deraillieur to work properly. Getting the chainline a few mm out messes up front shifting.

Shimano has quite a specific idea of how to measure chainline, which may not be what you expect, and probably needs vernier calipers to measure it. Can't find Shimano link right now.

[Tonyf33]

The cheaper e-type derailluers were often fitted to lower end hybrid bikes too, usually these has a large ring capacity somewhere around the 42-46 mark. However you could buy XT & XTR e types also.
As has been mentioned defining the reason to change the current chainset and its model along with your preferred replacement would help in determining what parts you're going to need.

[thirdcrank]

Take the bike in, point at the bit you want to change. New is "Nouvelle"? , I think a chainset is "La fourchete".

Gaz

I once linked to the TA site http://www.specialites-ta.com/

Somebody - and I thought it was you - pointed out that if you click on the union flag on the home page it is translated into English. As daft as it seems, because nearly all the text is just captions for pictures of TA equipment, toggling (if that's the correct computer lingo) between the French and the English versions is a pretty good way of getting a proper technical translation and much better than using a lot of non-technical dictionaries. (The English version is a bit dodgy, but we are looking for the right French term, not sneering at Jonny Foreigners, who do try this sort of thing better than we do.)

(FWIW 'La fourchette' is the 'the fork' = of cutlery size. It's a diminutive of 'La fourche' = 'the fork' of various sizes including a bike size.)

[gaz]

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[francovendee]

The bike is a Raleigh comfort MTB about 10 years old and was anything but comfortable when I first rode it!!!! I guess it is low end but the best bike I’ve owned and got me cycling again.
It is a bit of an odd bike all round as the e mount derailleur, Shimano C201, relies on a weird yoke around the seat tube as it doesn’t have a boss on the frame. This will be future problem as the derailleur is beginning to wear and I’ll have to replace it soon.
The only identification for the chainset is on the pedal arm and again is Shimano C201. I’m guessing the chainset and derailleur are a matched set? It has 42 teeth on the big ring.
The reason for the change is that the new chain doesn’t fit the teeth on the middle ring and tries to ‘jump’ off but does fit on the other 2. I’ve also replaced the rear cassette so I know that’s OK.
Some time back I changed the bottom bracket, which was a Shimano 116mm. I couldn’t find a Shimano of this size anywhere and ended up having to fit another make.
I cannot just replace the worn ring as the chainset is a riveted type. My plan is to fit one that does have replaceable chainrings and was thinking of Shimano Alivio as it seems be the price range I’d go to.
In my optimism I just hoped that all Shimano chainsets had the same dimension from the taper to the middle ring, hence a fairly straight swap with just adjustments to the derailleur.
I’ll look around for the best deal for an Alivio and take a chance.
Many thanks for all your replies

[squeaker]

It is a bit of an odd bike all round as the e mount derailleur, Shimano C201, relies on a weird yoke around the seat tube as it doesn’t have a boss on the frame. This will be future problem as the derailleur is beginning to wear and I’ll have to replace it soon.

Erm, I thought most Shimano front derailleurs clamped around the seat tube? Maybe I should get out more!

[AndyB]

The reason for the change is that the new chain doesn’t fit the teeth on the middle ring and tries to ‘jump’ off but does fit on the other 2. I’ve also replaced the rear cassette so I know that’s OK.

Can you not just change the middle chainring? Measure the BCD (see Sheldon's site), count the teeth, and get one ordered (as long as the number of arms and the BCD match you should be good; Spa cycles do a good range)!

[squeaker]

The reason for the change is that the new chain doesn’t fit the teeth on the middle ring and tries to ‘jump’ off but does fit on the other 2. I’ve also replaced the rear cassette so I know that’s OK.

Can you not just change the middle chainring? Measure the BCD (see Sheldon's site), count the teeth, and get one ordered (as long as the number of arms and the BCD match you should be good; Spa cycles do a good range)!

I cannot just replace the worn ring as the chainset is a riveted type

good old 'S'

[AndyB]

Can you not just change the middle chainring? Measure the BCD (see Sheldon's site), count the teeth, and get one ordered (as long as the number of arms and the BCD match you should be good; Spa cycles do a good range)!

I cannot just replace the worn ring as the chainset is a riveted type

good old 'S'

Oops, sorry I missed that! To be honest I didn't realise there was such a thing. Another reason for spending a bit more up front, if you can.

[gaz]

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[francovendee]

Gaz, this is the same as that's on the bike apart from being a clamp fitting. Mine is an emount (bottom bracket) type. I can buy emount deraillieurs but they all have a bolt that secures it to the boss on the frame and my frame doesn't have one. If there is a way to post a photo to the site I could show you the problem.