Creating compact set-up

[nirismo]

Evening guys, Hope everyone is coping with the cold mornings.

Every time after work I drive past a local bike shop which Giant bikes (thinking about getting one, lol) and decided to pop in to see what they have. So anyways, they had the TCR Advanced 3 (2012) in red which looked pretty sweet. Was hoping they had one in white. The thing is that is doesn't have a compact set-up 50/34 which I really dig! It currently has a 39x52T on the crank and a 12-25T on the cassette. Is there a way to make it so that it close to a compact set-up? Not just for this bike but other bikes aswell. Cheers.

Note: I'm not very knowledgeable in this.

Nirismo.

[Stuey]

Some people request a compact crank at the time of purchase and bike shops will usually accommodate them.

[Baalzamon]

btw I would never buy a white bike again unless you like cleaning

[macca33]

I'm sure you'd be able to negotiate something with the shop.

cheers

[Rockford]

Maybe a bigger cassette, 12-30 or something?

[open roader]

Some people request a compact crank at the time of purchase and bike shops will usually accommodate them.

+1

When i purchased my TCR Adv I told my LBS I'd only buy it if they could supply compact cranks and 11-28 cassette - I asked and I received.

You are the customer, go get yourself the deal you want.

[Xplora]

If they can't swap the crank, consider a different bike at the shop, or a different shop.

Trek doesn't sell any bikes with a standard crank - most people want a compact these days, especially if they are near hills. Also worth considering that if it DOES come with a standard crank, the likelihood is that the geometry and ride feel could be much more aggressive than you really want. Standard crank means sprinting for crits. Super fast, super short rides. I wouldn't bother putting different cassettes on the standard crank to make it easier to turn. Better to have a compact with a tight cassette, than a standard with a wide one.

[ab012]

If it is discounted they may not budge. However worse case is you having to buy another compact crank online (eg ultegra about $200 depending on where, luck etc) and get them to install and adjust. Guess roughly $50 bucks labour if they wont do it for free.

[nirismo]

+1

When i purchased my TCR Adv I told my LBS I'd only buy it if they could supply compact cranks and 11-28 cassette - I asked and I received.

You are the customer, go get yourself the deal you want.

If they can't swap the crank, consider a different bike at the shop, or a different shop.

Trek doesn't sell any bikes with a standard crank - most people want a compact these days, especially if they are near hills. Also worth considering that if it DOES come with a standard crank, the likelihood is that the geometry and ride feel could be much more aggressive than you really want. Standard crank means sprinting for crits. Super fast, super short rides. I wouldn't bother putting different cassettes on the standard crank to make it easier to turn. Better to have a compact with a tight cassette, than a standard with a wide one.

Looks like I'll definitely be doing this. With a 50/34 on the front is a 11-28 ideal? Or should I go with something else? They're asking $1,999 for it incl $300 of anything (which I don't need). I'll see if they can do $1,699 with Compact 50/34 and 11-28 cassette. If not I'll move on.

[Xplora]

How steep is that hill? Only you know the answer. I can charge up all the climbs in my area with a 39/23 combo easily enough, but going a little further out to the Blue Mountains and suddenly 34/28 was the bare minimum I needed to cope - and 36/28 had me stopping twice on Bellbird, even if I was recovering from a bad cold. 34/28 is pretty massive gear for climbing.... and mark my words, comfort on the big climbs can't come with comfort on the flats. I loved my 12-23 combined with 50/34. Perfect gearing for bunch riding the flats... but holy moly it sucks when you want to take on 10% for more than 10 minutes.

[kb]

... and mark my words, comfort on the big climbs can't come with comfort on the flats

Triple? I know it's decidedly unfashionable...

[barefoot]

... and mark my words, comfort on the big climbs can't come with comfort on the flats

Triple? I know it's decidedly unfashionable...

Also requires [1] a new shifter, so the double-to-triple upgrade gets quite spendy.

But if the option is there... I fully endorse the motion that they are decidedly unfashionable. Triple cranks give the best of all worlds. A nice tight cassette, nice overlap between the rings so you're not forever front-shifting like you are on a compact, and nice low winching gears for the odd occasion when you need them.

As for the OPs question - the smallest inner ring you can fit on a "standard" bolt pattern is a 38T - only just. 39T is more common. If you want a smaller ring, you need a smaller bolt circle... which means different crank arms. Either with a "compact" bolt pattern (110mm bolt circle diameter instead of 130mm on standard, which will fit down to a 34T ring), or with a second smaller bolt circle for a granny ring on a triple (standard road triples have 130mm and 74mm bolt circles, which can fit rings down to a 26T IIRC although 30T is more usual).

tim
who loves his triple


[1] I know there are some kludges you can do with certain double front levers to make them kind of triple compatible, but they're not the same as having a proper triple front lever.

[Xplora]

I find I get bad crosschaining issues using triples; if you lose a gear either side of the chainring, you only get 8 gears on a 10 speed in the middle ring, and most triples I have seen only do 8 or 9 speed (cheaper bikes though). So possibly 6 gears in the middle ring. Many of the benefits of the triple get lost if you have set up issues like I've experienced. This is only 2 gears on the double... big/big and little/little. Less wastage. There is far more efficiency in the rear deraileur changes, and a double shunts the work to the back. Sometimes we need to HTFU rather than shunt problems;

[simonn]

Super-compact FTW! 46/30 13-29. That's what I have on my audax bike - big difference doing 15% climbs having already ridden 2-300km to riding them fresh-ish , and you don't need to sprint on audax rides.

However, for a roadie 50/34 11-28 is pretty much ideal for Sydney. FWIW, I have 50/34 12-25 on my roadie, only because I had a 12-25 cassette kicking around.

[nirismo]

Alrighty, well the TCR Advanced 3 is out of the window. Guys overcharging for 2012 model so ain't gonna bother with them. The shop must be doing well (always got orders coming in so makes sense for them I guess). Anyways my plan B is purchasing a 2nd model (near new) off Gumtree and see if I can find a way to turn it into a compact set-up myself.

What would I need and how much to get a 50/34 and 11-28? Will be changing it on a TCR Advanced 2 (2014). It is easy for a dude like me who knows nothing about putting a bike together?

[open roader]

Easy enough to swap out Shimano Hollowtech II cranks - last time I looked it was a matter of purchasing the hollowtech crank tool which is inexpensive and undoing two grub screws on the non drive side crank arm which is done with regular everday allen keys

http://www.this link is broken.au/shimano-crank- ... owtech-ii/

Shimano 105 compact cranks will cost you $144

http://www.this link is broken.au/shimano-105-57 ... -chainset/

A Shimano 105 11-28 cassette will cost you $36 if you can wait for it come back into stock or an Ultegra 11-28 will set you back $51

http://www.this link is broken.au/shimano-ultegr ... -cassette/

This is simple swap out > swap in stuff assuming you have a chain whip and a cassette ring wrench........

http://www.this link is broken.au/bbb-btl-11-tur ... whip-tool/
http://www.this link is broken.au/bbb-btl-12-loc ... oval-tool/

If you don't want to buy the tools then the whole job will take a shop mechanic under an hour to complete so ask about for hourly rates / charges if you are not keen to do it yourself.

[herzog]

You'd also need to shorten the chain a touch.

[singlespeedscott]

Another option with standard cranks is to run a cassette with a 32t low and a GS length derailleur to take up the slack.

A 39x32 is the same as a 28x34 but you have the top end of a race bike with a 53x12, not that most people need a high gear like that.

[Xplora]

You'd also need to shorten the chain a touch.

If you are lucky, you'll cut it the right length ...

Same chain for me on
50/34 - 11/28
50/36 - 11/28
50/36 - 11/23
53/39 - 11/23

[open roader]

I did exactly the same when I had a TCR Adv. -that is swapped standard over to compact in the shop before I took delivery of new bike - same 11-28 cassette - the chain remained 'as is' and I cannot recall any drive issue / chain slop with that particular set up.

I'd do the swap over first, then ride to see if adjustment is required.