Two Question Thread - 110 bcd Cranks and Abus Amparo

[mickeg]

I recently built up a Nomad.  I am in USA so my parts sources are quite different.  I found a double Vuelta Corsa Comp square taper crankset for less than a typical set of crank arms.  They are available in both 110mm and 130mm, so if you order one, be careful to order the right one.  It was actually cheaper than the price of some chainrings.  I am not using the rings that came with it, instead I am running a chainguard/bashguard on the outside and the chainring on the inside. 

My chainline is roughly 5mm off, which I am quite content with.  If I put the chainring in the outerposition, it would be just right, but I prefer to have a chainguard in that position.  I knew that it would be off by about 5mm when I ordered the bottom bracket, I did not want my pedals to be more than about a half inch (about 12mm) wider than on my other bikes, thus I intentionally have a non-perfect chainline.
http://en.wikipedia.org/wiki/Q_factor_%28bicycles%29

I am using a 44t chainring and have ordered a 36h chainring to go with my 16t cog.  If I go somewhere like I was at last year where there could be some mountain climbing, I would put the 44t on the outside and 36t on the inside with no chainguard.  Then when I knew that I would be climbing for several tough days, I could remove a few links from the chain and switch rings before I embark on the mountain climbing.

[Andre Jute]

My chainline is roughly 5mm off, which I am quite content with. 

Be interesting to know whether the angled chainline cuts into the longevity of your chain or sprocket. Please report the mileage when eventually you change them.

I take it that you know you can get a chain tensioner for your Rohloff, and run a front derailleur so that you can operate two chainrings much more conveniently.

Andre Jute

[mickeg]

Be interesting to know whether the angled chainline cuts into the longevity of your chain or sprocket. Please report the mileage when eventually you change them.

I take it that you know you can get a chain tensioner for your Rohloff, and run a front derailleur so that you can operate two chainrings much more conveniently.

Andre Jute

I get long enough life out of derailleur chains, I am sure a 5mm offset in chainline won't be a chainlife problem.  I am pretty good about making sure my chain gets enough lube. 

I expect that 95 percent of the total distance I ride will have the chainguard installed, so the front derailleur would not be worth the time to install for the few miles I that I would fit the bike with two chainrings.  But, thanks for the comment. 

The plan to install the smaller chainring is only for trips when I know that I will be climbing really horrendously tall slopes.  Then the few minutes to put on some disposable gloves, remove a couple quick links and replace one, maybe adjust the eccentric and then reassemble should be a pretty quick modification to the system.  I only mentioned it because I was pointing out one other advantage to using crankarms that allow a double to be used on a Rohloff equipped bike.