MTB Groupsets

[MacB]

I'm building up a fully rigid XC 29er and my first plan was for a Rohloff but that is looking like being a future upgrade now. So if I go derailleur then the wheelset is going to be Hope ProII on Mavic TN719 rims, 36h and I'm looking at groupsets, for example this seems reasonable for a beginner and the M595 hydraulic discs get a stonking review on BikeRadar:-

http://www.merlincycles.co.uk/Bike+...c+Brake+9+Speed+Groupset_DEORE-DISC-GROUP.htm

bearing in mind that this will only be until I can afford the Rohloff rear wheel and I may upgrade the brakes in the future if need be. Thoughts on this groupset, pros and cons and alternatives appreciated...ta

 

[Zoiders]

Why so keen on Rohloff?

There were certain manufacturers the likes of Ellsworth turning out Rohloff geared MTBs a while back but I am not so sure if they took off due to the expense, there have also been tales of flange breakages, which is a big deal on such a pricey one shot component, yes the Bandits of Bridgewater are heavily into them as well but I remain unsold on the concept (as nice as it sounds).

Have you priced an Alfine disc groupset up yet?

The Deore kit is reliable enough I just would not trust the hollowtec in all weathers, I would rather a square taper myself, the organic disc brake pads tend to evaporate as well.

 

[MacB]

if/when I go Rohloff chain tension was planned via standard shell EBB, as I have on the Vaya, and you have to have a 2 piece 24mm axle crankset for this to work. All I'd need to do is replace the B cups with the EBB ones and use the outer ring to get the 54mm chainline for the Rohloff. If the H2 is really crap I can always switch to square taper and use the chain tensioner that comes with a Rohloff.

the Hope hubs are because I'm upgrading the Burls front wheel to a SONDelux and so will have a Hope front wheel for the 29er anyway, and would want the rear to match. Again if/when a Rohloff occurs then I would have a home for the Hope rear wheel anyway.

Good info on the pads, I don't mind if the first set didn't last great and I replaced with sintered. To be honest the review of the M595s mentioned this but was full of praise for ease of setup, modulation and ease of maintenance(a good thing for me).

Any way I look at it I'll need all the bits that come with this groupset anyway, I had set aside the dosh for the Rohloff wheelset but it was leaving me rather short for other stuff. By my reckoning this saves me about £900 on the build costs and allows me to get some other stuff I wanted. Rohloff wheel with OEM2 plate, Rohloff disc rotor, Speedbone/Monkeybone adaptor and the EBB were going to come to £1400.

 

[Zoiders]

I wouldn't trust an EBB anywhere near off road use.

Nooo noo nooo.

 

[MacB]

I wouldn't trust an EBB anywhere near off road use.

Nooo noo nooo.

tis a mini EBB and gets great reviews on MTBR forums for off road use with SS or hub gears...but I take your point and the Rohloff may be months/years away anyway

 

[Bodhbh]

I wouldn't trust an EBB anywhere near off road use.

Nooo noo nooo.

Eccentric Bottom Bracket? Why not? I notice all the Singular MTBs have them (and I have a Peregrine which might go off-road at somepoint).

Honest question, I don't know anything about the pros/cons of them!

 

[Zoiders]

Retention in position and the faff of set up more than anything is my doubt with them, I am not sold on standing on an eccentric BB in the attack positon for single track and descents, or giving it some welly from drop offs, it's a weak point I just don't I dont like the look of.

Some people think they might look neater or be a more elegeant form of engineering but I would go for sliding drop outs with a removable hanger myself everytime.

 

[MacB]

The Deore kit is reliable enough I just would not trust the hollowtec in all weathers, I would rather a square taper myself, the organic disc brake pads tend to evaporate as well.

Zoiders, just to come back on this bit, I've had a mooch around and the choices for non OBB chainsets seem to be pretty thin on the ground, or at least at the cheaper end of the scale.

did you have anything in mind?

 

[Cubist]

MacB does your budget stretch to SLX? I have it on two bikes now, and can't fault it. It's nearly as light as XT,looks the absolute bollocks and doesn't wear paint scuffs. You should be able to source some 9 spd at dead right money (Merlin, CRC, David Hinde, Ribble would be the searches of choice)

 

[MacB]

MacB does your budget stretch to SLX? I have it on two bikes now, and can't fault it. It's nearly as light as XT,looks the absolute bollocks and doesn't wear paint scuffs. You should be able to source some 9 spd at dead right money (Merlin, CRC, David Hinde, Ribble would be the searches of choice)

Yep it does, Merlin have the Deore disc brake groupset at £300 and the SLX 10 speed at £420...though I was trying to avoid being forced into 10 speed kit and the review I read was critical of the XT and SLX in comparison to the Deore for quality v value

 

[Cubist]

A non-native Yorkshireman now, I would go for SLX on looks alone!

I looked at the Merlin groupsets when I was building Cubester's Ragley. Cos I wanted and had budgeted for Hope brakes I ended up sourcing all the various bits from ebay and CRC. People tend to buy whole bikes for the frame and flog off the running gear, and various bike based powersellers like the woollyhatshop and absolutecycles occasionally have a real bargain, especially for cassettes and chains.

I bought my rear mech from the 'bay, and the chainset from CRC.

 

[MacB]

Have you priced an Alfine disc groupset up yet?

My first thought was the Alfine 11 but I have concerns about how low you can gear it, the spec recommends about 1.9 to 1 which is no good at all. Looking at the way the gears are spaced, and assuming a 56mm tyre, I reckon I'd want 1.5 to 1, this would give a range of 22.8 to 93.3 gear inches with the jump from 1st to 2nd being from 22.8 to 29.5.

I may seek advice from Shimano

 

[MacB]

Hmm, another of those seek and you shall find moments....the 1.9 to 1 is a suggestion for general riding not a limit and they also state that a double chainring can be used with a max variation of 16t with the alfine chain tensioner.

So it looks like alfine it will be and probably bung on the 24/40 chainset I just took off the Burls. Don't think I'll bother with a front mech, just change manually when needed. As I'd be using the Alfine tensioner the square taper will work fine and it's a Tiagra so the chainline will be down at Alfine levels anyway.

 

[MacB]

Just to be on the safe side I've e-mailed Shimano to get verification but a 1.5:1 ratio would be very good, I'm comparing it against my intended ratio of 2.5:1 for the Rohloff(this is the minimum they permit for tandem use or large people). Comparing the two in gear inches, using a 700x56 tyre I get:-

Rohloff Alfine11
20.2 - nothing
22.8 - 22.8
26.0 - nothing
29.5 - 29.5
33.5 - 33.4
38.1 - 38.1
43.3 - 43.3
49.3 - 49.2
55.9 - 56.0
63.6 - 63.4
72.2 - 72.3
82.0 - 81.8
93.3 - 93.3
106.0 - nothing

So basically the Rohloff mirrors what the Alfine would give, then throws in one slightly lower gear, the gear at 26 inches and the 106 inch gear. so if Shimano say that 1.5 to 1 is ok then I think Alfine 11 will be the answer.

 

[Zoiders]

Gearing it down enough was never a problem, tall gear inches are not really needed with with a rough stuff bike, I certainly don't think you would need a double chainring set up.