Velo Orange or White Industries cranks....some questions.

[djd828]

I am in the process of building up a new Raven and am considering the VO fluted crank or the White Industries Eno.  I really like the retro look of each. One thing I am not sure of is what BB spindle length to get if I go the VO route.  The double crank can be seen here:

http://store.velo-orange.com/index.php/components/cranksets/grand-cru-110-fluted-double-crankset-34x48t.html

I am also unsure if I should the double or triple crank would work better with the Rohloff (with the single chainring in the outermost position of whichever I choose).  Any help would be greatly appreciated.  The triple can be seen here:

http://store.velo-orange.com/index.php/components/cranksets/grand-cru-110-fluted-triple-crankset-24x34x48t.html

For the White Industries Eno, I have been told that a 125mm spindle length should work.  It can be seen here:

http://www.whiteind.com/mountain-cranks

Thanks,

Dave

[JimK]

Here is another clue for the ENO crank: http://0101.nccdn.net/1_5/300/188/182/ENO_CHAIN_RING_CLEARANCE_GUIDE.pdf

If 113 mm spindle gives a chainline of 47.5, and Rohloff wants 54. So we need another 6.5 mm. But double that to keep the spindle centered. Gives 126 mm spindle. Checks with the 125 mm you found elsewhere!

[JimK]

Sheldon says a standard road double chainline puts the outer chainring at 46 mm chainline: http://www.sheldonbrown.com/chainline.html

VO says a 118 mm spindle is the usual fit. But we want a 54 mm chainline, so 8 mm more than standard. 16 mm total for centered spindle. Seems like a good guess would be a 134 mm spindle. Do they make those??

[mickeg]

...
I am also unsure if I should the double or triple crank would work better with the Rohloff
...

Why a triple?

...or the White Industries Eno. ...
For the White Industries Eno, I have been told that a 125mm spindle length should work.  It can be seen here:
http://www.whiteind.com/mountain-cranks
...

I was not familiar with the White so I looked at that.  It said it has a wider Q factor.  That is not a problem by itself, but keep in mind that most cranks will take a longer bottom bracket spindle when used with a Rohloff, thus you already have a wider Q factor, which could be exaggerated if you also get a crank that inherently has a wider Q factor than other cranks.  I intentionally have a non-perfect chainline on my Rohloff bike because I wanted my Q factor to be closer to the same as on my derailleur bikes.  But if you would like a wide Q factor, go for it.

If Q factor is a term you are not familiar with, see:
https://en.wikipedia.org/wiki/Q_factor_%28bicycles%29

A side note:  Last month I was riding some single track in North Dakota USA that had some erosion on parts of the trail that made the trail look more like a gully.  Some parts of the trail were deeper than the elevation of my pedal at the bottom of the stroke and the trail was not much wider than the outside width of my two pedals.  There were a couple times that I accidentally dragged one pedal on the side of the trail/gully, which slowed me down and pushed me to one side a bit, that caused me to have to steer to one side, and my front wheel would start to try to climb out of the gully - but it did not climb up the side of the gully and I came to a rather sudden stop.  Fortunately I was not cleated in, so I never fell.  But from that I can say that I wish my Q factor was narrower, not wider.

[John Saxby]

Jim, Dave -

Just checking the arithmetic, without specific reference to a VO or White ENO crank and spider:

I used a Spa cycles (Stronglight/Sugino) double crank, which Spa said gave a 43mm chainline with a 107mm spindle. To get my 54mm chainline, I added 11 mm to the driveside length of the spindle, i.e., I used a 118 mm spindle, mated to a Surly 110BCD 5-hole ring (first 38T, now 36T).

Am I missing something?--why double the difference between spindle and and chainring centre?

So,

If 113 mm spindle gives a chainline of 47.5, and Rohloff wants 54. So we need another 6.5 mm

 

From my experience, we'd add 6.5 mm to the 113 mm, for a spindle length of 119 or 120.

[Tiberius]

Why consider a triple?
[/quote]

.....you beat me to it !!!

Great minds........

[JimK]

I have no experience with bottom bracket stuff at all, so my calculations are certainly not to be trusted! But I am trying to learn, so I figure if I jump in with my best effort, maybe I can contribute in some positive way and learn more, too!

Here is some discussion about doubling and halving chainline vs spindle length: http://www.parktool.com/blog/repair-help/chainline-concepts#article-section-2

in particular: "The chainline of the 118mm of this particular model 50mm. The 113 has a chainline of 47.5mm, or 2.5mm smaller. This is because in this case the 5mm shorter spindle is split between evenly between the left and right sides."

A big question is, how important / necessary is it to keep the spindle centered in the bottom bracket? Or, going the other way, what is the general range possible for de-centering the spindle, e.g. to push more spindle out the drive side, taking it in on the non-drive side?

[Danneaux]

A small note of caution:

Some BB spindles are symmetrical (same distance from the center to each end), while others are asymmetrical (the drive side sticks out further).

See: http://www.sheldonbrown.com/bbsize.html

Be sure to check for a/symmetry of a given BB before placing an order.

Best,

Dan.

[djd828]

Thanks everyone and to John S. who is helping me out on a variety of forums.  Here is VO's response to my BB question:

"With a triple crank, you could use the outer position of the crank and just add a 2 mm spacer to push out the ring to hit a 54 mm chain line. The triples are set up for the chain line to be 45 in the middle position. Add 7 mm for the difference between the middle and the outer ring and a couple of mm for a spacer and you're right about there."

I gathered from this info that, instead of using spacers, I could just add 2mm to the recommended BB spindle length (or should I be doubling it to 4mm for a symmetrical BB?).  Since the recommended spindle length for the triple is 124mm, I assumed that a 126mm would work to achieve the recommended 54mm Rohloff chainline.

As for the White Industries crank, they e-mailed me back that a 125mm BB will work to achieve the 54mm chainline....I think they have received this question many times in the past.  I have had that info concerning the WI Eno crank corroborated on other forums.

I never guessed bike building would have me brushing up on my math skills.  Lets hope it doesn't get any more difficult. 

[mickeg]

...

I never guessed bike building would have me brushing up on my math skills.  Lets hope it doesn't get any more difficult.

Wait until you work out the chain ring size you want.

[djd828]

Ha...don't even go there yet.  Honestly, I think this crankset/BB stuff will be the most difficult.  With the Rohloff, I think I have the gearing down to a 36 x 17 or 38 x 17 to start.   Then there is the bike size itself...then the perfect stem and handlebar....then....

Just can't wait till its done at this point but it is enjoyable getting this involved...it is forcing me to learn all the little details about the process.

Dave

[John Saxby]

As we say, Dave--some of us do, some of the time, anyway--the delight is in the details.  (Some of refuse even to acknowledge such bad jeux-de-mot.)   

[mickeg]

Ha...don't even go there yet.  Honestly, I think this crankset/BB stuff will be the most difficult.  With the Rohloff, I think I have the gearing down to a 36 x 17 or 38 x 17 to start.   ...

If you get the hub or rear wheel from SJS, it will probably have a 17T cog, anywhere else a 16T cog.