It would seem that a bike frame either fits or it doesn’t fit. It sounds simplistic, but it's true. That’s not the entire story, however. In the “doesn’t fit” category there are shades of gray. If a bike is off by a small margin, it is possible to perform minor retrofits to get the bike into an acceptable position so that the client can ride safely and comfortably. These can range from a different stem rise or length, to a change in the offset of the seatpost for instance. As the bike gets further and further from the optimal size for the client, the retrofits become more extreme and difficult to undertake. Finally, there are some clients who come into my Studio, for whom no amount of adjustment will make them comfortable, safe, or efficient.
In general, my experience has been that 90% or more of ill-fitting bikes are too large for their rider. That is a basic tenet I stress to my clients: “It's a lot easier to fit a bike that's a little too small, than one that's a little too big.”
they got as close as they could to the right bike, but the stock bikes available just don’t allow for an optimal fit for this client. Retrofits will need to be done, but they shouldn’t need to be terribly extreme. No major fault lies with the bike shop who sold them the bike, they just may not have had the training or experience in fitting to recognize how their clients deficits would limit them on the bike.
not acceptable. Anyone spending money on a new bike at the very least deserves to have customer service that leads them to what they need. If the customer vetoes a good recommendation in favor of another bike due to it’s color or components the shop is certainly off the hook. I haven’t found that this happens very often, though. More commonly, a client gets a very ill-fitting bike because of a shop’s (or shop employee’s) ignorance or arrogance. Ignorant because they may not know any better, or arrogant because invariably they are trying to sell the client what they have on the floor.
when it happens, but it certainly does. Ironically there is a bit of a switch in why this occurs. It is about equally as likely that the client insisted on a ill-fitting bike for cosmetic reasons (i.e. they just had to have a red bike, or the one with all the pretty components) than the shop being at fault. If the shop informed the client that they were a poor match for this bike, then, again, they are off the hook. In my experience, though, the shop often doesn’t speak up for fear of losing the sale. So if the frame is the wrong size we can just retrofit the bike and go along our merry way, right? Well, it’s not that simple. The amount of retrofits varies directly with how much the performance and handling of the bike is affected. It is important to view these retrofits as compromises. Just a few small compromises – maybe no big deal. But when you begin to make more and larger changes to the bike, that’s when things start changing for the worse. A bike frame consists of 6 main tubesets: the seatstays, the chainstays, seat tube, down tube, top tube, and head tube.
The most common changes are the ones that are an effort to make up for a "too long" top tube – again, most people have bikes that are too big for them, and this usually means trying to get the cockpit (from seat to handlebars) shorter.
2. Extra-short stems 3. Short and shallow handlebars
bike especially when climbing and descending. The riders weight distribution does not follow the same pattern as the bike’s designers intended. Almost any handlebar and saddle position can be accommodated for, but usually the “fix” for this would be to alter where the wheels are underneath you – an adjustment that can’t be done without re-fabricating the frame entirely (i. e. custom manufacturing). Too Low The next most common adjustment is to make the front end (handlebars) of the bike, higher. This is due to head tubes that are too short (but integrated headsets, 650c wheels, compact frames, and carbon steerer tubes also contribute to this problem). For too many years now, bike manufacturers have been building their professional race bikes and their lower end “weekend warrior” bikes with the same geometry, which usually includes a shorter head tube to accommodate the race position desired by the pro rider. Your average work-a-day 45 year old can’t assume the same position on a bike as a 23 year old professional athlete who rides 12,000 miles a year – it’s patently ridiculous to assume otherwise. But changing geometry means more tooling at the factory, which costs money, and the average big box bicycle manufacturer needs to get their bikes down to as few dollars per frame as possible. As I have said a few times, most people buy bikes that are too big for them – one upside to this is that the head tube is also going to be a bit longer, so the client may not need adjustment of bar height in this case. More often than not, however, even with the bigger bike I often find instances where the front end is still too low. Ways to get the front end higher: 1. Higher rise stem 2. Steerer tube extenders 3. Lowering seat excessively (to decrease the differential between seat and handlebar height) When trying to make a “too short on the front end” taller, the effect to the handling is only slightly less pronounced than shortening the cockpit. The reason is that when you raise or lower the bars, the riders weight is still shifted either forward or back upsetting the balance of the bike. So there are options if your bike doesn’t fit well, but it is important to know that there are compromises that will be made. Often these compromises will be entirely acceptable and the rider may adapt to them, but when they don’t a custom bike may be the best option. |