Shimano Stx Rc

[iainpik]

Hi there,

I’m looking for some help concerning the above, I have a 42T-32T-22T with all chain rings worn and needs replacing.

From what I understand these- chainring are no longer available to buy? and have 94bdc or 95?
Distinguishing marking on the chainring are K-42 / SG / Shimano IG / K-32/ K-22
So perhaps the simplest option is to replace to crank which I’ve noticed are available from Amazon already assembled quite cheaply

https://www.amazon.co.uk/Shimano-Al...ano+chainset+crank+42+32+22,sports,69&sr=1-16

But I’m unsure of my existing crank diameter, does anyone know the specs of what I have now is it a MC-FC33? or if the above is compatible.

As you can guess I’m new to bike refurbishing and any help is appreciated.



Thanks

iain

 

[Markybeau]

You'll likely need a new chain and possibly a cassette as well. You should be able to pick up new rings. They don't have to be Shimano. 94bcd 5 bolt is what you need.

Your cheapest fix would be to start by cleaning all that gunge and crap off the drive system. Then lube it up again and see if that improves things. Putting new lube on old dirt = years of wear in a few days

 

[iainpik]

You'll likely need a new chain and possibly a cassette as well. You should be able to pick up new rings. They don't have to be Shimano. 94bcd 5 bolt is what you need.

Your cheapest fix would be to start by cleaning all that gunge and crap off the drive system. Then lube it up again and see if that improves things. Putting new lube on old dirt = years of wear in a few days

Thank you for your reply.

I pheraps should have included a little more detail.

This bike has been unused for the past 15 yrs, and is having a program of refirbishment,
its had a new chain, back cassette, tyres, Rearderailer cable and works much better now, but still some adjustment required it has a tendacy to slip to the middle ring when going up hill? so im thinking the chainrings?

the cleaning kit has just arrived so i agree a good clean and lube is a good place to start.

in your opinion does the chain rings look worn?

thanks

iain

 

[bikeworkshop]

The middle ring was almost immediately unavailable as a spare, and if course its the one that wears fastest.
The chainset you pictured is just too horrible. stx-rc was a nice groupset and you need to find a polished chainset with removable rings, preferably a commonly available size.
You should be able to find something nice in good order, like a sugino, or similar, on ebay.
Am old-school lbs ought to be able to help, but there aren't so many of those around. we have a box of them, but forus it's not worth posting really, our time related overheads are huge.

 

[bikeworkshop]

Or go original,
This one's in a lot better condition than yours:
https://www.ebay.co.uk/itm/38783584...fKWcIN2RE6&var=&widget_ver=artemis&media=COPY

 

[legrandefromage]

Also be aware that the original STX groupset had 95mm bcd outer ring that sat on the spot welded inner/granny combo.

I don't know if they carried on this nonsense for the RC chainset leaving a very hard to find bcd if true.

Even without that potential headache, 5 bolt 94mm bcd rings are getting harder to find

 

[iainpik]

Thanks you all for your assistance, im getting a headache now, so whats the opinion on a new crank and are they universal size through the bike frame?, amazon have 4 post cranks with new chainsets already attached ready to play, bringing it upto date with easier to change parts in the future, its just that whist the 2nd hand ones £26 wheres new is about £15 more?

 

[bikeworkshop]

Thanks you all for your assistance, im getting a headache now, so whats the opinion on a new crank and are they universal size through the bike frame?, amazon have 4 post cranks with new chainsets already attached ready to play, bringing it upto date with easier to change parts in the future, its just that whist the 2nd hand ones £26 wheres new is about £15 more?

If you need much technical detail you might be better off in a bricks and Mortar shop, not amazon.
If you can find one locally.

There are different bb axle lengths, especially if you change brand, period or style.
There are quite a few pitfalls to be avoided.

If I was fixing this bike, I'd buy that same chainset, as it will go straight on and look better than the cheap modern black one.