27.Jul.2011 | chris
Ill be doing a little “Rules of Thumb for Bike Fitting” Presentation as part of the Lloyd Transit brown bag lunch series, on September 14th. I just finished putting together a little hand out to cover some basics that I have picked up through my years of coaching and working at bike shops. It might not solve every fit problem your experiencing, but it might help. The best bet is to go talk to a professional in person to have your position assessed and have the changes made that you need based on good body mechanics and position, given from an experienced eye. But, in the mean time, enjoy these little tips to help you find more comfort in your ride!
Initial Fitting Guidlines
Seat height-Stand straight against a wall, wearing whatever shoes you intend to ride with, then measure your inseam by holding a book horizontally, bringing it up between your legs, holding it firmly to you and the wall, step over the book(or have someone else measure) and measure the distance from the top of the book to the floor. Then take this number, multiply it by 1.09, and this should be the distance from your pedal at the BOTTOM of the stroke(measure your pedal in the 6 o’clock position, in line with the seat tube) to the top of the saddle.
Seat position-Level is key – the saddle should be perfectly level, or a slight tilt down in the nose. Too much forward tilt will cause you to slide off the saddle, causing back pain as your core and shoulder works to stabilize you on the saddle.
Fore/Aft saddle position – make a plum bob using a weight of some sort and a string. While seated on the bike, have your feet and pedals at 3 and 9 o’clock, have the plum bob dangling from the end of your femur by feeling your knee cap, then slide just to the inside of your leg, to where it is hard bone, and you have dropped off your knee cap(this is the femur) drop the weighted string from this point, it should be at or behind the spindle of the pedal.
Upper body-you should be able to COMFORTABLY reach your brakes and shifters. While sitting within reach of the brakes, you should have your arms slightly bent. Ideally, you want some weight on your arms and to not be in a completely upright position-this takes some weight off your sit bones(less saddle sore!) and allows vibrations to be more evenly disbursed through your core, and not up your spinal column as you ride. It also allows some more weight on the front wheel, producing better control and braking of the bicycle.
Common pains, possible causes, and possible fixes
Pain in the back of the knee- Saddle too high(lower saddle!), saddle too far back(slide forward!).
Outside Knee pain- Saddle too low(raise saddle!), Tight Hamstrings(Stretch!), Toes pointed in on pedals (point further out).
Inside knee pain-toes pointed out(point more inward!) stance on pedals too wide(narrow stance).
Front knee pain- Saddle too low(Raise Saddle!), Saddle too far forward(Slide back on rails!), Cadence too low(pedal faster in easier gears!), Crank too long(buy a shorter crank).
Neck and Shoulder pain- Saddle has too much tilt (neutralize/level), improper reach to handle bars(get shorter/longer stem), Handle bar too low(raise handle bars).
Low back pain-Handle bars too far away(get smaller stem/smaller frame), Bars too Low(raise), Too much tilt in Saddle(Neutralize/level saddle), poor core strength/leg flexibility(core work/stretch legs especially ham strings).
Chris Swan-Upper Echelon Fitness Cycling Coach – firstname.lastname@example.org – (541) 556-8815
Sore hips – Saddle is likely too low (raise saddle!).
Numbness or painful hands-too much tilt in saddle(Level saddle), not enough padding(new bar tape/grips/gloves), improper reach(shorten/lengthen stem).
Numbness or Pain in feet-poor cleat position, shoe too small(size up for cycling shoes!), shoe not stiff enough(cycling specific shoes are STIFF to distribute weight).
Pain/discomfort on sit bones-wear cycling specific shorts(have pads built in, and less chafing as well!), try a different saddle(more padding does not always mean more comfort! Some shops allow you to demo saddles), more time in the saddle(not what people usually want to hear, but it works!).
These are only some TIPS, getting a perfect fit to your bike takes time, trial and error, and experience. Once you have a fit you like (and definitely before you make any equipment changes on your bike), be sure to take the measurements of the distances from your saddle to pedals, reach to bars, drop in bars, and position of the saddle. One other thing to keep in mind is that there are subtle differences between equipment sizes. For example, if you purchase a new saddle, the new saddle may sit shorter from the rails to the top of the saddle, effectively lowering your seat post when you put on the new saddle. Always measure and re-measure when replacing/trying out new parts. If you still are not achieving comfort while on your bike after trying some home trouble shooting, talk to your local professional bike fitter about scheduling an appointment to be fitted to your bicycle. Keep in mind, that many local shops don’t offer a professional level fitting, just a basic fitting with a few tools to get you in the ball park, so don’t be afraid to shop around a little for the right person. An experienced eye of someone who fits several people a day, experienced in body mechanics and focuses on body mechanics in cycling can make wonders! Riding your bike should not be an uncomfortable experience!