Help choosing compact and cassettes for hills

ScottieP

Hi Everyone

I've been reading up on the forums for a few days now on Compacts and have now decided to make the change. I'm hoping for advice specifically on the choices of Shimano Compact that I'm considering, whether they are 9 speed compatible and which make and model of cassette I should order as well.

I have a Specialized Allez Elite (2005 model) which is full 9 speed Shimano 105 and is unchanged from the factory spec (including the "lovely" Alex wheels).

I am considering (in order of preference):
Shimano R700 (says 10 speed only on some of the websites I've been viewing)
Shimano R600 (same query as above)
Shimano 4550 (Tiagra) which I can see is 9 speed compatible

Can anyone put my mind at rest over the R700 compatibility with my 9 speed drivetrain or share any thoughts over which one I should choose?

With respect to cassettes, the standard one I have is 12-25 but I'd ideally like to go to 12-27/28 without changing my 105 rear mech if I can. The Shimano 105 (9 speed) cassette that I have is only available up to 12-25. Can I use other Shimano cassettes like the 9 speed Ultegra instead? or are there other brands I can use that will be compatible? or am I simply "stuck" with a 12-25 cassette?

Sorry to be pedantic - but this is all new to me and I want to order the right bits.

Thanks for all help!

Cheers
ScottieP

redddraggon

You could get an SRAM 11-28 cassette

Lagavulin

I'm running a couple of Ultegra 9 speed 12-28's on my standard double Allez Sport (2006).
Not sure what the original cassette was but the rear mech is 105.

I'm buying a new bike soon and despite it having a compact 50/34 chainset I'm not sure what to do with regards the cassette.
Certainly think I'll need 12/25 but perhaps something even bigger.
I don't encounter mainy hills around here but those I do seem to go straight up! :oops:

dennisn

Shimano makes a 9 speed 12-27. Not sure about 10 speed. TA Specialties makes a
33 tooth front ring that fits Shimano compacts and others like FSA. At least they used to.
I bought one and only use it for mountain rides.

Dennis Noward

Babbsy

dennisn wrote:

Shimano makes a 9 speed 12-27. Not sure about 10 speed.

Yep, I have a 12-27 10 speed ultegra. It has the same gearing as a 12-25 except the 23 and 25 are replaced by a 24 and a 27. Gives you a little bit extra.

John.T

Any of those chainsets will be OK. The only real difference is weight and price. TheR600 and R700 have a slightly smaller gap between the rings but you would only notice this if you ran in the little/little combination which should be avoided if possible.
You can get a 12/27 cassette in Ultegra 9sp. No 12/27 in 105.

Lagavulin

Lagavulin wrote:

I'm running a couple of Ultegra 9 speed 12-28's on my standard double Allez Sport (2006).

Oh no you aren't! :P

Sorry, just checked (both cassettes and CRC invoices) and they were 12-25's.
That gives me 42.1 as my lowest gear. Perhaps 50/34 and 12/25 will suffice after all.

Mettan

ScottieP wrote:

I am considering (in order of preference):
Shimano R700 (says 10 speed only on some of the websites I've been viewing)
Shimano R600 (same query as above)
Shimano 4550 (Tiagra) which I can see is 9 speed compatible


Cheers
ScottieP

I've had the 4550 fitted this week - am generally quite pleased - perfectly adequate budget Compact, although if you've got the money I'd go for something "lighter/better". I'm currently using a Shimano 11-32 HG40 cassette and a Shimano Altus rear mech with it - the setup's been great so far, in particular further into a ride when you've got some 1k 5-7% 's and you want a break. Feels a bit weird on the flat though - sort of caught between the 34 and a very small sprocket (which is not particularly nice) and the 50 and a big-ish sprocket (with all the chain rub on the front cage.......). Will take a week of getting used to.

John.T

You should not get chain rub on any of the gears exept perhaps the 34/12. If you set up the front mech correctly and use the trim facility you can use all the other gears. Only use the 50/27 in emergencies when your head was better than your legs. I have this set up on 3 bikes, 2 on 10sp and 1 on 9sp. I do miss the 16 cog on the 9sp but it is better than never using the big ring in winter with a 53/39 set up. One of the 10sp bikes has a SRAM Rival chainset and I can run all 20 gears with no rub. The other one with Ultegra SL just rubs the inside of the big ring when on the 12, usable but not recomended. The 9sp was OK on all 18 with a Shimano chain but rubs now with a SRAM which has slightly longer pins. With the trim none of them have chain rub on the front mech.

ScottieP

Hi All

Thanks for the replies so far .... if I understand correctly the Ultegra 9 speed in a 12-27 should work with my 105 9 speed rear mech? If so, I think I'll order one of those.

Still not sure about which compact. I'm not a good cyclist and I'm surrounded by hills so I'm reluctant to put more weight on the bike, hence I'm leaning towards the R700 as it looks like a quality piece of kit(which can be bought online for about £90. which doesn't seem too bad). The other option is to buy the 4550, which looks excellent value - but is not light.

More thoughts/advice are definitely welcome..... I am also looking at new wheels but can't justify doing this altogether (including wheels) right now. So it's gearing first then wheels in the spring.

ScottieP

musto_skiff

John.T wrote:

and use the trim facility

What's that?

When I go onto the big ring I can click the lever to shift it back to the small one and it just suffles over a bit ... then if I push it again it shifts to the small ring ...

Is that the trim facility?

John.T

The Ultegra cassette will work fine. All Shimano 9sp cassettes have the same spacing so you can use any 'Road' cassette with your 105 mech. 27 teeth is Shimano's recommended biggest cog.
There is not a great deal of difference in weight between the R700 and the 4550. The 4550 is probably no heavier than what you have at the moment. Put the money saved towards some better wheels later.
It would be a good idea to get a new chain at the same time as yours is probably a bit worn by now and you will need it one link shorter anyway. Correct chain length is important with 50/34 and 12/27 as you are very close to the limits for a short cage mech. It works fine when set up correctly.

willbevan

I had a 28 sunrace cassete on okay with a shimano sora short cage rear mech that was okay, never heard a problem or anything.

Now being that im attempting to do longer cycles (did 80mi on sunday that was excpetionally long for me) i wanted those granny gears for up the nasty hills so bought a SRAM 11-32, now the sora rear mech did cope with it, just, but i wouldnt recommend it as you could hear the teeth catching if you shifed under hard load, quickly swapped it for an old XT long cage rear mech I had and no problem, but then that can take upto 34 i think as have the same mech on my trek fuel with a 34 rear lol, as large as my smalles compact chainring

John.T

Musto. Yes that is the trim. When the front mech is set correctly and you are on the big ring the chain will not catch the cage on 5 or 6 of the smaller cogs. When you move down to the larger end of the cassette it will start to rub. The small 1/2 click will move the cage just enough to give clearance for the rest of the gears. Likewise the trim on the larger lever will move the cage out to give clearance when running smaller cogs on the inner ring.

Mikey1280

willbevan wrote:

I had a 28 sunrace cassete on okay with a shimano sora short cage rear mech that was okay, never heard a problem or anything.

Now being that im attempting to do longer cycles (did 80mi on sunday that was excpetionally long for me) i wanted those granny gears for up the nasty hills so bought a SRAM 11-32, now the sora rear mech did cope with it, just, but i wouldnt recommend it as you could hear the teeth catching if you shifed under hard load, quickly swapped it for an old XT long cage rear mech I had and no problem, but then that can take upto 34 i think as have the same mech on my trek fuel with a 34 rear lol, as large as my smalles compact chainring

Will have you still got the 52-42 on the front on your decathlon? I'm tempted to change this first to a compact before fiddling about at the back.

John.T

Better to go for a compact as MTB cassettes will give wide ratio gears which are not so efficient for road riding. You are either spinning your legs off or pushing too high a gear. Also if you are struggling on hills you do not have much use for a 52/3 * 11. I seldom use my 50/12 even in races.

Mikey1280

Good point about the spread there John. I think I'll go for a 50/34 compact and keep my 12-28 on the back. One more question, even though the chainsets say 10 speed they should work fine with an 8 speed chain right?

redddraggon

Mikey1280 wrote:

One more question, even though the chainsets say 10 speed they should work fine with an 8 speed chain right?

Yeh, it'll be fine.

Mikey1280

redddraggon wrote:

Mikey1280 wrote:

One more question, even though the chainsets say 10 speed they should work fine with an 8 speed chain right?

Yeh, it'll be fine.

Thanks redddragon

musto_skiff

John.T wrote:

Musto. Yes that is the trim. When the front mech is set correctly and you are on the big ring the chain will not catch the cage on 5 or 6 of the smaller cogs. When you move down to the larger end of the cassette it will start to rub. The small 1/2 click will move the cage just enough to give clearance for the rest of the gears. Likewise the trim on the larger lever will move the cage out to give clearance when running smaller cogs on the inner ring.

Thanks ... I had figured that was a deliberate feature of the gears :oops:

ScottieP

Do I need any other tools than a chain wip to remove then install a cassette? Is this a job that someone with no experience can/should do? (I would have thought it was). Thanks.

I'm going to get my LBS to install the compact.

Thanks
ScottieP

John.T

You will need a lockring remover as well. It is not difficult. Make sure the LBS face the BB before they fit the crankset.

Mettan

John.T wrote:

You should not get chain rub on any of the gears exept perhaps the 34/12. If you set up the front mech correctly and use the trim facility you can use all the other gears. Only use the 50/27 in emergencies when your head was better than your legs. I have this set up on 3 bikes, 2 on 10sp and 1 on 9sp. I do miss the 16 cog on the 9sp but it is better than never using the big ring in winter with a 53/39 set up. One of the 10sp bikes has a SRAM Rival chainset and I can run all 20 gears with no rub. The other one with Ultegra SL just rubs the inside of the big ring when on the 12, usable but not recomended. The 9sp was OK on all 18 with a Shimano chain but rubs now with a SRAM which has slightly longer pins. With the trim none of them have chain rub on the front mech.

Thanks John - I'll look into some front deraileur adjustments.

ram038

John.T wrote:

You will need a lockring remover as well. It is not difficult. Make sure the LBS face the BB before they fit the crankset.

What do you mean by "face" the BB. I am thinking of going to a compact but have not heard that expression before

Mikey1280

ram038 wrote:

John.T wrote:

You will need a lockring remover as well. It is not difficult. Make sure the LBS face the BB before they fit the crankset.

What do you mean by "face" the BB. I am thinking of going to a compact but have not heard that expression before

BB Shell Facing

John.T

The ends of the BB tube should be faced as in Mikey's link if you go from a 'normal' Bb unit to one with outboard bearings such as Shimano Hollowtech 2 or Campag Ultra Torque. If you already have these then the compact should fit straight in to the existing BB cups.

ScottieP

Just wanted to say a belated thanks for all the help on this. I've decided that I'll probably go with the R700 and an Ultegra 12-27 .... just need to scrape the pennies together. In the meantime I'm trying arrange my routes to ride down the local 10%+ hills rather than up them!

Thanks again.
ScottieP