[steady lad]

Folks

I might be getting a new Roubaix Elite (the entry level one), it comes with a 50-34 praxis alba chainset.

I’m tempted by the idea of changing it to the praxis alba 48-32 featured on this website today.  The logic being that I even if I was worn out at the end of a long ride I’d still be able to ride up anything with a 32-32 gear.

Are there any compatibilty issues that I might not have thought of?  I’m intending to just put it on, lower the front mech a bit, maybe shorten the chain and away I go. I assume there will be no front shifting issues but i’m not certain…

 

Thanks for any help.

 

Adam

 

 

 

Topic

[steady lad]

Ok thanks all, if i do get

Ok thanks all, if i do get that bike I’ll stick with the 50-34 for starters at least.

Cheers

[Carton]

It’s a braze-on FD, so height

It’s a braze-on FD, so height might be an issue, and chain drop thus a concern. I’d ask the bike shop for their take. If you’re keeping the old set I’d definitely try for the 46, seems a little more worthwhile. 46-11 is still a bigger gear than an old school 52-13.

[TypeVertigo]

Duncann wrote:

Can’t see how there would be – it’s still a 16t jump, and only 2t smaller rings, so not like the difference in mech cage curvature you might see between a MTB (44t max) and a standard road cage (53t max). But maybe others know different…?

Road front derailleurs can still handle a 46/36T cyclocross chainset, so as far as big ring curvature is concerned a 48/32 won’t be a problem. At least that’s the case with my 105 5700 unit.

With a 46/36 crank the tail of the cage is pretty far away from the big ring though.

Ultimately your main concern should be the amount of travel your front derailleur mount/adapter has. It should be able to go low enough to accommodate your desired set of chainrings, be it a 48 or 46. On a band-on front derailleur this shouldn’t be a problem.

[. .]

I’m not sure it’s worth it.  

I’m not sure it’s worth it.   My lowest gears are 34/32 on one bike and 34/34 on the other, admittedly slightly heavier, one.   I’m hard-pressed to tell the difference.  Either way I’m defeated by certain  local hills.

[steady lad]

Duncann wrote:

Can’t see how there would be – it’s still a 16t jump, and only 2t smaller rings, so not like the difference in mech cage curvature you might see between a MTB (44t max) and a standard road cage (53t max). But maybe others know different…?

Thanks, I was thinking along the same logic myself.

[Dnnnnnn]

Can’t see how there would be

Can’t see how there would be – it’s still a 16t jump, and only 2t smaller rings, so not like the difference in mech cage curvature you might see between a MTB (44t max) and a standard road cage (53t max). But maybe others know different…?

[Author]

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