The Hollowtech II bottom bracket is a class of external ball bearing bottom brackets. The Hollowtechs have the advantage of being able to run a hollow and larger diameter crank axle: more axle strength with a comparable or lower weight than a square taper BB while still being compatible with standard BSC/ISO/English threaded bottom bracket shells. The disadvantages are the ball bearings are smaller and the large, exposed seals that could fail prematurely, taking the bearings with them.
> When I built up the Homer, the M590 bottom bracket specified a spacer combination to make it MTB spacing (73mm, 50mm chainline), and again the road derailleur was struggling. In this case I rearranged spacers to move the entire BB and crank 3mm left to solve the chainline problem. The chainline for the FD-3030 is 45mm ( https://bike.shimano.com/en-EU/product/component/sora-r3000/FD-R3030-F.html) so you moving the chainline to 47mm moved the front rings closer in line with its intended use. The chainline on external bearing bottom brackets are adjusted just as you did, by moving spacers between the drive- and the non-drive sides of the bottom bracket, and works fine as long as your small ring still clears your chainstay. Also, note that the FD-3030 is spec'ced at 20T capacity (the largest and smallest rings can't differ by more than 20 teeth) and the differential between top and middle rings can't exceed 11T. All options for the stock M590 crankset ( http://media.canyon.com/download/manuals/Manual_FC-M590_EN.pdf) come with a 22T differential and a top-to-middle differential of 12T. Maybe that's why you're having front shifting problems? If so, Jeremy's suggestion with replacing the Sora with an M590/M591 FD ( https://www.bike-components.de/en/Shimano/Deore-FD-M590-FD-M591-66-69-3-9-speed-Front-Derailleur-p22104/) with its 22T capacity and 12T top-to-middle differential could fix that. > The latest Shimano Deore stuff seems to be heading towards 10-speed and 175mm crank arm length. Rivs don’t like a 175mm crank due to the low bottom bracket, so I’m stuck with 170mm. 170mm is my preferred crank length and I have no problems finding one for any of the "modern" drivetrains. I think if you prefer 165mm or 180mm, that may be a bit more challenging. For many offroad, non-MTB applications, the "adventure compact double" 46T-30T paired with a wide range rear cassette (11T-34T on my Ultegra 6800; 11T-42T coming up more often with off-the-shelf RDs) is the preferred choice for gearing. Here's Russ from Path Less Pedaled on gearing for mixed terrain gravel riding, covering light to fully loaded touring (caution: long video and very bike nerdy): https://www.youtube.com/watch?v=qL7HLXR3O9U . > But are folks putting 10-speed equipment (cassette and chain) on a Riv? If so, what problems have you run into? [lack of shifters?, etc.] It's just a matter of selecting drive train components (FD, RD, shifters, crankset, BB, and rear cassette) that work together on your target frame, whether or not it's a Riv. The 68mm BB shell/135mm rear spacing/28.6 seat tube clamp diameter is so ubiquitous that your AHH will not be your limiting factor. The problem will be if you'd like to keep some of your old drivetrain (and other components) as you add in that 10 speed group to your existing 9 speed group. (The answer is likely nothing practical, and it's most cost effective to upgrade everything at once.) > I know this is all heresy. This is not heresy: this is orthodoxy. Glad to see you playing around, and hope the tinkering works out in the end. --Ed C. -- You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/rbw-owners-bunch/a0d67a31-8de6-48a4-b0c4-4ca4575992c0%40googlegroups.com.
