I'm sure you know this, but to summarize, tread depends on model of crank and bottom bracket width, which in turn is dependent on clearance at the chain stays. What I can say from my experience is that the narrowest tread can be had with a TA Pro 5 Vis or VO Grand Cru crank providing the chain stays allow a narrow bottom bracket. If you want a wider Q factor, you only need insert a wider bb.
Having said that, today, after not having been on my bike for a couple weeks, I rode a new bike with about 5-7 wider tread than my old bike. I noticed the difference immediately in my foot placement but put it out of my mind and rode in a spirited ( for me ! ) manner. That is, I applied myself with some effort, and pedaled at times from the knee, if that makes sense, and at times from the hip. At the end of the ride the most noticeable thing for me was a lack of left knee pain that had been plaguing me for some time. What I initially noticed with some annoyance turned out to be a blessing in disguise. But we'll see - it's really too soon to say anything definitive. 2010/9/25 PATRICK MOORE <bertin...@gmail.com> > The stock bb and XD2 on my Sam Hill had a Q of just about 160 mm > (which is just about as much as I can tolerate; adding MKS touring > pedals, with their relatively wide platform and relatively wide gap > between arm and cage, made the Q unwieldy). Fortunately, the same bb > and cranset (170s in my case) swapped over perfectly to the Fargo > with the left arm clearing the left stay by about 2 mm. > > On Sat, Sep 25, 2010 at 2:03 PM, andrew hill <neurod...@gmail.com> wrote: > > hi folks, > > i'm looking at building up my next Riv in some road-ish configuration for > a > > fast/light trainer.. this will probably going to be based on a canti-Rom > (or > > a Roadeo), and i want to make good choices to help alleviate some knee > > problems i've had with my Sam Hillborne. > > the Sam has a Sugino XD2 with 175mm cranks, and i experienced some rather > > bad ITB pain on the right side starting 60 miles into a century. at the > > time i thought it was because i was clipped into the pedals and didn't > have > > enough float, and while i do think some cleat mis-adjustment might have > > contributed, i've continued to have some minor pain in that knee all > summer > > when doing short rides (6 miles) while using only platforms (after taking > > almost 2 months off riding to allow it to heal). > > so i'm wondering if the Q factor and crank length are something i should > > change on my next bike. > > some relevant info - i'm 5'11 but with a pbh of 84.5 (rounded up a few > mm), > > so i've got short legs and long torso. in addition, i rode a 19" Gary > > Fisher Cobia 29er for the past few years and never experienced even a > twinge > > of pain doing 12-30 mile rides, and ~ 75+ miles a week with clip-ins; the > > Fisher also had 175 cranks, and a Q-factor of 166. I believe the Q on > the > > SD2's are about the same (165), but i'm not sure what the BB width that > came > > with the Sam is, so it's possible the Fisher had a larger effective Q...? > > i'd like to go back to SPD clip-ins, as i never had a problem before my > > century ride last june, and based on some recent threads on this list, > i'm > > planning on going with a shorter crank.. i'm thinking 170mm, as i doubt > > 172.5 will make much of a difference (but i'd love to hear dissenting > > opinions). > > also - anyone know how "typical" the Q the Sam with stock BB and SD2 is? > > any advice on how to minimize ITB issues when setting up a Riv in a > road-ish > > fashion? i'm assuming i DONT want to go for a compact double with narrow > Q, > > but might want to get a wider BB or a set of cranks with a larger tread. > > thanks, > > andrew > > > > -- > > You received this message because you are subscribed to the Google Groups > > "RBW Owners Bunch" group. > > To post to this group, send email to rbw-owners-bu...@googlegroups.com. > > To unsubscribe from this group, send email to > > rbw-owners-bunch+unsubscr...@googlegroups.com<rbw-owners-bunch%2bunsubscr...@googlegroups.com> > . > > For more options, visit this group at > > http://groups.google.com/group/rbw-owners-bunch?hl=en. > > > > > > -- > Patrick Moore > Albuquerque, NM > For professional resumes, contact > Patrick Moore, ACRW at resumespecialt...@gmail.com > > -- > You received this message because you are subscribed to the Google Groups > "RBW Owners Bunch" group. > To post to this group, send email to rbw-owners-bu...@googlegroups.com. > To unsubscribe from this group, send email to > rbw-owners-bunch+unsubscr...@googlegroups.com<rbw-owners-bunch%2bunsubscr...@googlegroups.com> > . > For more options, visit this group at > http://groups.google.com/group/rbw-owners-bunch?hl=en. > > -- Kathryn -- You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group. To post to this group, send email to rbw-owners-bu...@googlegroups.com. To unsubscribe from this group, send email to rbw-owners-bunch+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/rbw-owners-bunch?hl=en.
