Rear Derailleur for 105 5700 Shifters

photonic69

Hi all esteemed workshop gurus

Just bought my daughter a mint condition Felt bike. She's coming from a Red B'Twin Triban 3 with a triple on the front to this 105 set up with a 25 biggest sprocket on the rear. It's a short cage 105 derailleur and max size is 28 (possibly squeeze a 30 on there) but the options for cassettes to fit are limited.

Would a 10 Speed Tiagra rear derailleur be compatible? Pull ratios?

e.g. http://www.wiggle.co.uk/shimano-tiagra- ... illeur-gs/

I could then get her a 11-32 cassette. We live in a hilly area and she moans a lot on the hills.. she is 11..... :roll:

keef66

No, annoyingly they changed the pull ratio for 10 speed Tiagra, so you need 10 speed 105 or Ultegra, or 9 speed Tiagra. Not sure of the max sprocket size for those though.

But as I understand it you could fit a 9 speed Shimano MTB rear mech which would allow use of larger cassettes, and will work perfectly with the 5700 shifters

Sportiveman

If you have a 5701 rear mech you can run a 12-30 Cassette after that you will need to either for a long Cage mech or 9 speed mountain bike one for a 11-32 to fit .

photonic69

Keef66 - thanks for the info. Damn, that's annoying. I guess the 105 RD-5701 Rear Derailleur is the way forward with this. It was £9 more than the Tiagra.

Does the fact that the Tiagra pull ratio is different mean that Tiagra cassettes wont fit either? I was looking at this:

http://www.wiggle.co.uk/shimano-tiagra- ... 11-3211-34 as the 11-32 option as the Medium cage 105 will take 32 rear cog.

keef66

Cassette sprocket spacing is the same so you're OK to use the 10 speed Tiagra. But bear in mind that while the 10 speed 105 has the thin 10 speed spacer, the Tiagra cassette has it built in.

photonic69

Thanks Keef66.

So the spacer is on the inside of the freehub nearest the spokes on the 105 cassette? So I need to make sure I remove this before putting the Tiagra cassette on? Or is it on the outside next to the lockring?

I was looking at 11/12-30 cassettes but in 10 speed they are almost as much as a Tiagra cassette and a new mech (or very much not in stock)

Looks like the really good deal I got on the bike is costing me yet more money..... but isn't that always the way with bikes

timothyw

You could also run a Sora r3000/3500 rear. They're 32 tooth cassette compatible and have the same pull ratio so will work despite nominally being for 9 speed.

Ask me in a couple of days about it if you like, I've actually just had one arrive to replace a worn out old 5700 derailleur on the winter bike.

photonic69

Thanks TimothyW. Please do let me know ASAP so I can benefit from my extra Wiggle discount that ends on the 12th. I might just go 105 as the price difference is not huge.

keef66

PhotoNic69 wrote:

Thanks Keef66.

So the spacer is on the inside of the freehub nearest the spokes on the 105 cassette? So I need to make sure I remove this before putting the Tiagra cassette on?

Yes, it goes on the freehub before the cassette. Thin (1mm?) metal spacer. Well on my 10 speed Shimano freehubs it does anyway.

Other wheels / freehubs may use additional spacers

svetty

If she's only 11 and struggles with hills I'd definitely consider a 9sp mountain bike mech and a 34 or 36 tooth cassette. It works perfectly with the 5700 shifters.

photonic69

Hmmmm.... After a first ride yesterday evening it seems I'll need to do a bit more fettling! LHS shifter for FD is very stiff. She's not strong enough to shift safely. I hear that 5700 shifters suffer from sticky cables and hard shifting. I'll order new Teflon cables for this. Also noted the FD is a Sora. Pulling on cable on down tube it seems quite stiff too. It's a band on. Should I replace this too? Would Tiagra suffice here? Seems like it has a good lever on it for best mechanical advantage? Or should I go 105 (more expensive) for easier, better shifting?

arlowood

PhotoNic69 wrote:

Hmmmm.... After a first ride yesterday evening it seems I'll need to do a bit more fettling! LHS shifter for FD is very stiff. She's not strong enough to shift safely. I hear that 5700 shifters suffer from sticky cables and hard shifting. I'll order new Teflon cables for this. Also noted the FD is a Sora. Pulling on cable on down tube it seems quite stiff too. It's a band on. Should I replace this too? Would Tiagra suffice here? Seems like it has a good lever on it for best mechanical advantage? Or should I go 105 (more expensive) for easier, better shifting?

If your daughter is struggling with the FD changing then I'd steer clear of a new/replacement 5700 FD. Shimano changed the length of the actuating arm when they introduced the 5800 series and this was repeated when they brought out the Tiagra 4700. In the images below you will see the short arm on the 5700 compared to the longer arm on the 4700

5700 FD


4700 FD


The longer arm gives more mechanical advantage and should make the changing a bit easier assuming all cables are correctly routed and running freely. Look out for a second hand 5800 FD or a new/second hand 4700 FD

crankycrank

PhotoNic69 wrote:

Hmmmm.... After a first ride yesterday evening it seems I'll need to do a bit more fettling! LHS shifter for FD is very stiff. She's not strong enough to shift safely. I hear that 5700 shifters suffer from sticky cables and hard shifting.

Yes, cable routing is critical with the 5700. You want to create as straight a path from the exit of the shifters and under the bar tape as possible. When done properly it should have fairly easy movement.

photonic69

keef66 wrote:

Cassette sprocket spacing is the same so you're OK to use the 10 speed Tiagra. But bear in mind that while the 10 speed 105 has the thin 10 speed spacer, the Tiagra cassette has it built in.

Got all the bits. Fitted CS-HG500 10 speed 11-32 cassette without the very thin spacer but as I tightened the lock ring the main body still rattled. So took it off and replaced thin washer. No rattles. Is this right?

keef66

PhotoNic69 wrote:

keef66 wrote:

Cassette sprocket spacing is the same so you're OK to use the 10 speed Tiagra. But bear in mind that while the 10 speed 105 has the thin 10 speed spacer, the Tiagra cassette has it built in.

Got all the bits. Fitted CS-HG500 10 speed 11-32 cassette without the very thin spacer but as I tightened the lock ring the main body still rattled. So took it off and replaced thin washer. No rattles. Is this right?

Yes, that's right. The Tiagra specific 10 speed cassette was CS-4600. Don't think they produced one for Tiagra 4700. All the other 10 speed ones need the spacer.