Gearing change from 3x9 to 2x10?

A16UYF

Hello all,

I was just wondering how much work is involved in changing my gearing from 3x9 to a 2x10 set up and more importantly what i'd have to change (buy) to do it.

Probably a bit of a newbie question but i like doing things myself rather than paying a LBS to do it for me.

Cheers in advance A16UYF

nicklouse

basically a whole new drivetrain less cranks.

see the topic in the FAQs.

delcol

everything.
shifters, mechs, chain, and crank...

no9ismine

Nick, I keep seeing people pointed in the direction of the FAQs but can't find them myself, could you please point me there?

nicklouse

at the top of this forum
hard to miss

viewforum.php?f=10004

lostboysaint

Why 2x10? I'd stick to 2x9 and then you only need to change the chainrings, add a bash guard (optional) and adjust the stops on the front mech! (Although I changed to a specific 2 ring chainset)

Go for an 11-34 cassette and a couple of decent sized front rings (mine are 27 and 39) and there's very little loss of gearing and very little that you'll be able NOT to ride.

no9ismine

Thanks Nick

delcol

+1 for what lostboy says.

when i built the butcher last year i went 2x10 and to be honest i aint overly impressed.. when the time came to change the drive train on the chromag i went 2x9 instead...
and the soda i just built last week i opted for a 1x9..

The Rookie

Running 2x9 here with 26/36 and an 11-34.....no need for the expence of 2x10 when 2x9 just requires new rings and a bash or shorter bolts.

plugp7

Running 2 x 9 with 22 & 36 up front with BBG bashguard and 11 to 34 at back. Will change to SLX M665 double specific when I can be arsed but adjusting the existing XT 3 ring mech works fine. Simple.
BTW, the chainline for double is 46.5mm compared with 50mm for a triple. Anyone actually bothered doing the adjustments for this?

The Rookie

The Chainline stays the same (47.5mm or 50mm depending on bike) it's how you use it (middle between rings or for me, as I use the 36T ring 80% of the time I leave that on the chainline).......if your going to bring up chainlines get it right!

nicklouse

The Beginner wrote:

The Chainline stays the same (47.5mm or 50mm depending on bike) it's how you use it (middle between rings or for me, as I use the 36T ring 80% of the time I leave that on the chainline).......if your going to bring up chainlines get it right!

I love it when people bring up chain lines as no one gets it correct.

you have missed out a whole load more. not to mention that to two big suppliers measure differently.

:twisted:

plugp7

The Beginner wrote:

The Chainline stays the same (47.5mm or 50mm depending on bike) it's how you use it (middle between rings or for me, as I use the 36T ring 80% of the time I leave that on the chainline).......if your going to bring up chainlines get it right!

The Beginner..... says it all.

May I suggest you read Sheldon Brown's article on this subject and also:-
http://www.parktool.com/blog/repair-hel ... e-concepts

The Rookie

Thanks Plug read it but already new it, there really is no need if (like most people) you spend the majority of time in what was the middle ring, if you go nearer to 50:50 then you need to change the crankset to match the same original chainline....so your original post was still wrong.

Nick, agree I've heavily sumarised, but as it's not relevant to the OP, didn't see the point, most people running double and bash use the old middle ring 80% of the time and just swap the outer for a bash.

plugp7

The Beginner wrote:

Thanks Plug read it but already new it, there really is no need if (like most people) you spend the majority of time in what was the middle ring, if you go nearer to 50:50 then you need to change the crankset to match the same original chainline....so your original post was still wrong.

Nick, agree I've heavily sumarised, but as it's not relevant to the OP, didn't see the point, most people running double and bash use the old middle ring 80% of the time and just swap the outer for a bash.

The chainline for a SLX M665 front mech is 46.8mm. This is from the the Shimano technical spec. Now call me naive, but I tend to believe the manufacturers of components that if you want optimum performance, you follow their advice. No need for a new crank, changing the bb will do the job, if I need to.

You are perfectly right in saying that if you want optimum performance in the old middle ring you leave well alone.
Your statement however, that the chainline stays the same for the M665 mech is wrong.

......if your going to bring up chainlines get it right!

The Rookie

So the mech won't work with a 'normal' (Most common) 47.5mm chainline, of course it will, few bikes/parts are that precisely made that you could get within 0.8mm anyway!

Besides looking at the link you provided I don't see the front mech being measured to determine chainline.....

plugp7

The Beginner, you just don't understand the concept.
Bored now.

cooldad

plugp7 wrote:

The Beginner, you just don't understand the concept.
Bored now.

Do you have the Audi to go with the avatar and attitude?

plugp7

cooldad wrote:

plugp7 wrote:

The Beginner, you just don't understand the concept.
Bored now.

Do you have the Audi to go with the avatar and attitude?

Right on time.

cooldad

plugp7 wrote:

cooldad wrote:

plugp7 wrote:

The Beginner, you just don't understand the concept.
Bored now.

Do you have the Audi to go with the avatar and attitude?

Right first time.

ryanincontrol

As mentioned above, I'd stick with 2x9 & 11 - 34 cassette.
I have on mine the SLX double and bash 22/36 and a double specific FD SLX m665.
It's so easy to set up and I'm very happy with it.

The Rookie

plugp7 wrote:

The Beginner, you just don't understand the concept.
Bored now.

No, you don't.......

denis's mate

Seems like the prefered option is 22 & 36 and 11 to 34 for 9 speed. I've gone this way as well. Using the SLX double mech. Sweet,

The Rookie

I didn't get on with 22/36 as the number of shifts required when dropping into the granny to get just one gear below the gearing in the 36 was too much, so I popped on a 26.

denis's mate

The Beginner wrote:

I didn't get on with 22/36 as the number of shifts required when dropping into the granny to get just one gear below the gearing in the 36 was too much, so I popped on a 26.

Yes I know what you mean but I use gripshifts, so no time loss shifting. 4 clicks and your there. Also I need the range as lungs and legs aint what they use to be!!!!!!!

The Rookie

If it works for you, that is great, 4 shifts is only 2 presses on the lever, not sure I'd be happy with Gripshifts (I use them on my commuter so know the upsides).