Monday, December 9, 2013


This fall I've been lucky enough to have friends get upgrades, giving me the opportunity to get some used components to upgrade my bicycle.  As such, I was able to replace the OEM equipment that came with my Scott S40 (which was mostly Shimano Sora-level equipment) with a SRAM Force/Rival groupset, along with a set of OEM brakes from Pinnerello.  While it would seem like the new groupset would be the bigger focus, the brake really made a big difference in how the bike handles downhill.  I didn't realize just how poor the braking power was on that bike until I had new brakes on the exact same bicycle.  

That isn't to say that the SRAM drivetrain didn't change the feel of the bike.  Much of the feel that I got from the SRAM ride experience in late October has come through quite clearly even without a frame update.  It may be psychosematic, but the bike seems to feel better overall since the change.  It's taken several rides to get used to using double-tap for shifting instead of the thumb-shifting on the Sora, but the transition has been very smooth.  The biggest issue for me so far has been accidentally shifting to a smaller cog when I'm at the top of the cassette.  The new crank is VERY slightly longer (175mm vs 172.5mm), and after a few rides I've gotten used to the changes there as well.  

Earlier in the year I had signed up for a contest sponsored by Retül, and as a part of it I received a coupon to get a fitting.  After getting the new groupset, and realizing that it had been 18 months plus more than 6,000miles since my last bike fit, I figured now would be a good time to make sure the bike was properly adjusted to my fitness.  Bad form on the bike can relate to injuries in the long term.  Injuries that you cannot recover from with a little bit of rest.  I made an appointment to go in to Greenville Cycling Center and get a Retül fit.  It was worth every penny spent.

Even though the weather was a little bit poor, I decided to just ride down to GCC, as it is only about 3miles from work on the Swamp Rabbit Trail to their offices.  I got there a little early, so I had a little time to relax and be amazed by the CompuTrainer setup.  I made sure to wear one of my sleeveless base layers, as I was told.  

Jason and Jim started out by putting my bike onto the trainer they had set up for fittings, making sure that the bike was level.  The Retül system looked at a very basic level like a really big XBOX Kinnect sensor.  You could see multiple cameras facing the bike at a set distance, and they had the data set up on a big TV at one side of the trainer for review.  The trainer was on a platform and had a Kurt Kinetic fluid trainer and a Retül device coyly named a Levül to help make sure the bike sat level.  They replaced my rear skewer with a trainer skewer that had a knob on the end to give a spot to mount a level to make sure that the bike was on level before doing any adjustments.

They asked me the standard battery of questions (height, weight, cycling goals), and then took my measurements (outseam, arms, wingspan, etc).   From there they set up a table for me to lie down on to test my flexibility and core strength (definitely not my strong suit).  Jim went through several stretches and exercises ranging from arching my back to push-ups to one legged squats.  It definitely brought home the work that I needed to focus on during the off-season, as my core definitely needs work (that plus doing push ups on a padded table isn't a whole lot of fun).  Jim also noted that my hip flexibility, especially inward, was very poor.  Time for more stretching!

After completing my fitness evaluation, it was on to getting the bike adjusted!  They started by noting the current measurements on the bike.  The saddle was (once again) pointing nose up, along with slightly left.  The nose up part was definitely an issue, and they corrected it (once again) back to level.  We chatted for a bit about a new seat post, as this one has had the "nose up" issue a bunch this year.  It's definitely a future investment on my radar.  The next step was for me to get several velcro dots applied at my joints so that the Retül camera could track my motions.  

Once dotted up and having the sensors applied, I had to ride at approximately 90rpm for 30s while the camera recorded the motion on my right side.  They then spun me around and had me spin again at 90rpm for 30s to capture the motion on my left side.  This allowed them to not just look at how the bike fit me, but also how I was tracking while pedaling without just "eyeballing it".  They found 2 issues that they wanted to correct immediately:  First was that I was sitting too low, and thus not fully extending my leg at the bottom of my stroke.  The second is that my knee wasn't tracking straight;  noteably the upstroke was curving slightly outward.  They also noted that my hips shift such that my right side is pushed slightly forward.  The hip shift didn't concern them, but the knee motion did.

The first adjustment was to raise my saddle by 10mm!  This doesn't sound major, but in bicycle fit terms, small amounts are huge adjustments.  The second was to attempt to fix the knee track by adding in spacers on my pedals.  After making the adjustments I ran the test again (30s @ 90rpm for each side) to see if the tracking was better.  The saddle height fixed most things, but the pedal spacers didn't help the knee motion

For the second adjustment they removed the pedal spacers and placed shims in my shoes.  Without seeing my street shoes, Jim could tell that I underpronate while standing;  That is to say that I walk/stand on the outside of my foot.  This is of note because even going into running stores it takes the fitters a few iterations of measurements and triple-checking the wear pattern on my shoes for them to really believe I underpronate because it is so uncommon.  He also was hopeful that the shims would also help my knee to track more evenly.  After another 30s @ 90rpm for each side (anyone else feeling like this is cooking instructions yet?) my knee tracking was slightly better on the left side, but not magically better.  Everything else was dialed in almost perfectly, so we are hopeful that if I focus on core and stretching that my knee will start tracking in where it should be.  

The end of the appointment was spent going over the report generated by the Retül software.  The detail in the report was incredible, and it really made me comfortable that my fit was really dialed in.  I was still a little concerned over my hips being shifted, along with the difference in crank length between my original OEM equipment and the new Rival crank I had just installed.  I was assured that the neither was an issue.