Chainrings for Shimano Deore XT FC-M771 Hollowtech II 48x36x26 (9 speed)?

[raggydoll]

Hey,

I have a Cube SL Cross Team from 2010:
https://www.thebikelist.co.uk/2010/cube/sl-cross-team

Been looking recently at which chainrings would fit but can't seem to find much.
They are ok just now, just wanted to have some in reserve for when I need them.
(I like to keep a little stock of consumables like cassettes, chains etc).

Never replaced chainrings before so worried that they won't fit the cranks.

I've read some stuff that says that as long as the BCD is right they should fit but don't want to order something that may not fit.

As per the title,
Shimano Deore XT FC-M771 Hollowtech II 48x36x26 (9 speed).

Also:
Are triple chainrings different from double chainrings?
Do chainrings need to be the exact speed?

Again, i've read some people say that 10 speed works etc, and some who say the shifting won't be great.

I would rather get the right size, speed for the model ideally.

Cheers.

 

[Cycleops]

Found the inner;
https://www.sjscycles.co.uk/chainrings/shimano-deore-xt-fcm771-64mm-bcd-4-arm-inner-chainring-26t/
Just a question of searching. Looks like buying a complete chainset is going to be almost the same price as the rings.
https://www.decathlon.co.uk/p/triple-chainset-with-30-39-50-teeth-170-mm-shimano-sora/_/R-p-197566

 

[raggydoll]

Thanks Cycleops

If it was a cheaper crankset I'd be happy to buy a new crankset but the deore st is a really good quality crankset (perhaps slightly outdated). Found it on a site for around £160. Out of stock of course.

Annoying how components go out of date so quickly sometimes.

Really like the smaller ring sizes too.
So good on the hills.

I'll keep hunting!

 

[Cycleops]

I think you'll find that any of the four bolt Shimano rings should fit, like Deore. likehttps://www.evanscycles.com/brand/shimano/fc-m590-deore-4-arm-chainring-975755 the Deore.

 

[raggydoll]

Some man!

So any 9 speed 4 bolt rings should work if I find the right teeth number?

 

[andrew_s]

It's not necessarily that simple.

According to google, it's a 104/64 bcd 4-arm symmetrical chainset, which gives you these chainrings:
Spa Cycles outer middle inner (TA aren't the cheapest by some way, but they are good, and available in most sizes).
SJSC various outer/middle inner

As has been said, it's often cheaper to replace the whole chainset than all 3 chainrings.

 

[raggydoll]

Now I'm even more confused!

 

[raggydoll]

See - something like this...
Triple
9 speed
104BCD
36T (so would fir the middle size)
Designed for ALIVIO cranks.
Deore XT is listed on the pack but they don't seem to have the 36t or 48t that I can see.

You think the one below would fit a deore xt crank?
Or do they make the different crank models slightly different to make you buy the specific rings?.....if they still made them!

 

[Cycleops]

I can't imagine Shimano making two four bolt ring types, so as I said stick to Shimano.
Can't say that's gospel but should work. Just make sure your supplier has a good returns policy

 

[raggydoll]

Haha, yeah I think that's the worry.
With older parts you really need to find on the internet. Shops don't tend to stock them.
I'll keep an eye on the returns policy though!

 

[andrew_s]

See - something like this...
Triple
9 speed
104BCD
36T (so would fir the middle size)
Designed for ALIVIO cranks.
Deore XT is listed on the pack but they don't seem to have the 36t or 48t that I can see.

You think the one below would fit a deore xt crank?
Or do they make the different crank models slightly different to make you buy the specific rings?.....if they still made them!

View attachment 591587

Yes, that will fit.
There's only one 104 bcd 4-arm size, so as long as it says 104 mm, it can be fitted.

Outers are a bit more awkward, as the rings are sometimes meant to be blended in with the contours of the chainset, so there's the chance of the chainring tab interfering with the crankset centre, which may mean having to file down part of the tab to allow it to fit.
Examples

---

I can't imagine Shimano making two four bolt ring types, so as I said stick to Shimano.
Can't say that's gospel but should work. Just make sure your supplier has a good returns policy

They do.

The older ones are simpler, but nowadays there are the gravel bike groupsets where the 4 bolts are arranged at the corners of a non-square rectangle. To make it worse, many of the alternative chainring sources are using slightly different rectangles to Shimano's.

 

[raggydoll]

This video shows someone with an xt crankarm who has to file a deore chainring to make it fit.

I might need to do that if it comes to it!

View: https://www.youtube.com/watch?v=sRpAAwYeNgs


Never easy!

 

[andrew_s]

I have the advantage that I'm still using the original MTB triple, which has been the same since Shimano started making MTB parts, way back, and which is still readily available at modest prices (£38 chainset). The relatively minor downside is that the smallest chainring is 24T
(110/74 mm 5-arm).
It started as MTB, but was sufficiently popular with touring and commuter use that it didn't die when MTB went micro/compact drive (min chainring 20T), and had a revival when roadies realized that gears lower than those available with a 39T chainring could be useful and came up with the (road) compact double, which used the same outer bolt pattern.

 

[raggydoll]

I think the deore xt is basically a touring setup...48/36/26

The small ring in your link is 28.

Crazy to think how mountain bikes especially have gone from triples to doubles to singles.

On a related note, another one of my bikes is a triple too and I spent so long setting up the front deralleur.
Made me yearn for a 1x bike!

 

[Blue Hills]

On a related note, another one of my bikes is a triple too and I spent so long setting up the front deralleur.
Made me yearn for a 1x bike!

is it flat bar?