Upgrading/Repalcing cassette, need advice...

[Widget]

Hey guys,

So I'm going to be buying a new chain, current one is pretty worn and bike shop guy suggested a replacement cassette as the chain was really worn (showed me). Though, I'm on the fence on what to get.

My current setup is Shimano 105 5600 10spd dated pre-2010. My cassette seems to be 12/25. Having limited finds, im tossing up between the Tiagra 4600 10spd and 105 5700. From what i've read, the 4600 is on par with the 5600, maybe a tad heavier, but cheaper, or should i spend the extra $ and go 105 5700?

is the 105 worth the extra $ ?

At the moment, Im recreational rider and just starting to dabble in Du/triathlons (did my 1st a few days ago) (road bike, not a tt bike)

Also, having the 5600 derailleur, im not sure of the limitations, whether I need to stick with 12/25 or can i go higher to a 12/30 ?

Any suggestions would be super.

im pricing the parts from chainreaction cycles (as I need bearing covers and can only find them at c r c)

Thanks again

[dalai47]

Shimano 105 5600 is listed as 27t max, with total capacity of 29 - (subtract small chainring teeth from big chainring + subtract smallest cog from largest) total number needs to be 29 or less.

http://si.shimano.com/php/download.php? ... 01-ENG.pdf" onclick="window.open(this.href);return false;

People will say they have run bigger cogs so you may be able to fit a 30t, but you have to weigh up the risks and decide for yourself.

As to cassette - go with what you can afford. Shimano 10 speed cassettes are fully interchangeable from what I understand. As to chains, I swear by KMC chains which include a quicklink joiner.

[Derny Driver]

I would go
12-28 Tiagra 4600 cassette off CMC for $22.99
Ultegra chain for $24.99

[Duck!]

There is very little to be gained through different level cassettes. 105 are a little lighter than Tiagra due to the bigger sprockets being pinned to aluminium carriers, where Tiagra is all steel (with plastic spacers), but the shift tooth contouring and hardening treatment are the same, so performance and durability are likewise the same. Ultegra cassettes are the same weight as 105 (ok, so the aluminium lockring shaves a few g), but the surface hardening is better, for a little more durability. again the shift tooth profiling is the same, so there's no difference in shift performance.

I would not advise fitting a cassette with bigger than 28T with a 5600 RD, it just doesn't have the clearance.

As far as chains, with different levels the link shaping is the same, so a better one isn't going to shift any better than a cheap one, but the anti-corrosion treatment gets better as you spend more, and that does translate to better chain wear. Dura-Ace chains are lighter thanks to hollow pins, but Ultegra, 105 & Tiagra all weigh the same.

[Widget]

Thanks guys

I was leaning more towards a 28 to begin with, I dont do many hills but wouldnt mind a lil easier gear than the 25. With the cranks, they're 52/38. The large ring says 52/36T, not quite sure what that means as the 2nd smaller ring is 38. There's only 2x chain rings on the bike. That would mean, ((subtract small chainring teeth from big chainring + subtract smallest cog from largest) total number needs to be 29 or less. )) total comes to 27.

Not quite sure what any of this means, but am i limited to a max of 27t on the large cog? I've had a bit of a good, seems other have managed to go higher..but.. im not 100% sure of the version (ss/gs) RD they have. how does one find out whether they have an SS or GS ?



Thanks again guys,

[Duck!]

The 52/36 printed on the big ring indicates that it is a 52T and the ramping on it is designed to pair with a 36T small ring. The 38 you have isn't an ideal match, but workable.

As far as rear derailleur, SS refers to standard or short cage, GS refers to longer (now commonly called "medium" thanks to MTBs adopting a shorter version from their traditionally long cages). A short cage is about 55mm between jockey wheel centres, a long (GS) cage is about 75mm - the difference is pretty obvious. However that does NOT determine the largest sprocket you can use; that is a result of the length of the upper body of the derailleur and where it positions the top jockey wheel, and for any given model of derailleur is the same for both cage lengths. The longer cage is used to carry the extra chain length required for use with a triple-ring crankset. At the time the 5600 series was current, super wide range cassettes (30 or 32T big sprocket) were the exclusive domain of MTB gearing, so the derailleur isn't designed to cope with anything bigger than 28T; if you needed more you went a triple up front. The capacity, derived from the combined difference between big & small rings + big & small sprockets refers to the amount of chain the derailleur can carry. If your gear range exceeds the capacity of the derailleur, you will wind up with a chain that is too long, or worse, not long enough, which will cause damage.

[cjrich]

PLUG: If you decide to go with 12-25 I have a brand new 105-5700 for sale for $25 + postage, but I agree you may be better with a 28 with your semi-compact crankset.

[Derny Driver]

Front derailleur looks too high?

[Duck!]

Nah, looks fine to me.

[Widget]

Hey guys, looking back over the post, Im thinking.. if I wanted my harder gear to be a little harder, and my easier gear to be a little easier, I would be looking at 11/27+ ??

[Duck!]

Correct, a smaller sprocket = higher gear ratio -> harder gear, larger sprocket = lower gear. With the range capacity of your rear derailleur, the widest cassette you can fit is 11-28. Should you find yourself needing to go bigger than a 28 then you will need to replace your RD with a newer model that has clearance for a bigger sprocket.

[Widget]

Thanks duck. probably wont go higher than 28.. the only issues im concerned with is,

"(subtract small chainring teeth from big chainring + subtract smallest cog from largest) total number needs to be 29 or less. "

52 - 38 = 14

28 - 11 = 17

total = 31 .. which is higher than the 29 limit?

With my large chainrings.. am I stuck with 12/27 or 11/25 cassette ? Sorry for sounding like a broken record.. just a little confused :/

I checked my RD too and it seems to be the SS Short Cage version.

[Duck!]

Shimano's capacity specs do tend to be on the conservative side, so exceeding the recommendation by a couple of teeth won't be a problem.

Chainring size doesn't directly affect what cassette you can use with a given derailleur; the critical thing is the difference between the two rings. A "compact" crankset, with smaller 50 & 34T rings actually has a greater difference - 16T vs 14T - than a more traditional configuration, which needs to be considered.

A common misconception which I continually seem to be correcting is that a longer cage allows the fitting of a bigger cassette. That is not the case at all; big sprocket capacity is governed entirely by the geometry of the derailleur's upper body, as that is what determines where the top jockey wheel sits under the cassette. A medium cage (GS) derailleur of any given model (for Shimano at least, I believe SRAM derailleurs have different bodies for wide-range versions) has the same clearance and big sprocket capacity as the SS version. What the long cage does is carry the extra chain required to cover a wider gear range, traditionally gained by the use of a triple-ring crank, but more recently by the use of very wide-range cassettes + compact rings.

Short version: 11-28 will be OK with what you have, just.

[Widget]

Thanks Duck!, much appreciated

[Widget]

Hey Guys, just an update.

I ended up picking up the 105 5700 cassette. I installed it but ran into an issue.

The screw cap that came with the new cassette (the cap that holds the cassette into the hub), the threaded section is too bit for mu hub, so I had to use the previous locking cap... but... it looks like that cap might be a bit on the wide side, and feels like it overlaps the bottom portion of the teeth by a millimeter, so if I were to put the chain on and go into the low gear, I think the chain will be hitting the edge of the locking cap.

Im not sure what hub I have, but is it possible to buy (cheap) a replacement lock cap that may thread into the hub, but not be so wide?

Sorry, I cant remember what to call these things. here a couple pics, hope you can help

PIC #1 - Using previous locking cap


PIC #2, comparing New cap (left) with old cap (right)

[Duck!]

Did you fit the supplied 1mm spacer behind the cassette? If not, the lockring will bottom out before the cassette is fully tightened.

You cannot fit the lockring from a cassette with a 12T or bigger small sprocket to a cassette with an 11T, for the reason you have discovered - it's bigger! 11T sprockets actually cover the ends of the splines on the freewheel body in order to get the diameter down tight enough to fit on, whereas 12 or bigger fits fully outside the splines, hence the different sized lockrings (you can see in Pic 2 that the new ring doesn't actually seat on the 12T, it drops in the centre).

Fit the spacer (the shape of the old lockring suggests to me the old cassette was a SRAM unit not Shimano, so wouldn't have had a spacer, just to confuse you) and use the lockring that came with the cassette. Problem solved.

[Widget]

hey Ducky.

With the spacer, I didnt have one on my old cassette, someone said it didn't need it because of the design of the hub(?), so I left it off the new one too.. but will add it back on and see how it goes.... problem is, the new lockring doesn't actually fit the hub :/




the new lockring sits ontop of the hub and cant be threaded. The old lockring seems to be a couple mm smaller, and can thread no problem.

I could have sworn my old cassette was a shimano 105. The rest of the bike has 105 5600 :/. On the old lockring, it says '10 speed / R1-025".. locks like a "Fulcrum" lockring... not sure what that means though :/

only thing i can think of now is to either sell the cassette, find/buy a new lockring that will fit the hub and 11t cassette... or plug in the bench grinder and modify the old locking...

[EDIT] Upon further reading, it seems Fulcrum freehub = Campagnolo freehub = fulcrum/campagnolo 11t lockring required (diameter is different than shimano).. can anyone confirm in-case I've misunderstood ?

[Duck!]

Lordy, what a mind-bender! That is indeed a Shimano 10-sp.-specific hub, so no spacer required. Fulcrum are made by Campagnolo, which partially explains the smaller thread diameter, but I find it weird that they made it with the Shimano spline pattern but Campag thread (Campag cassettes use a different spline pattern). A Campag lockring for 11T will set you right.