How much does weight affect fit
 

If a person is say, 100lbs overweight and gets a bike fit, will the same bike fit when they lose that 100lbs, or will they need another fitting done?

They'll actually eed another fitting. The apparent length of their legs will be longer, for one thing, since they will have less posterior, or at least that was my experience. ;) I had to raise the saddle many times, and it wasn't from post slippage. (I marked the post to keep track).

It's more than just weight loss. As you bike more, your muscles adjust and adapt, and your ideal position will change. Even if you don't shed 100 pounds, you'll need a different fit after getting used to biking. With the weight lose that will be even more pronounced.

I heavier rider needs an upright fit. This aids breathing, and takes a load off of the lower back muscles.

As the rider loses weight and gains strength the handlebars can come down. This is even more important if the rider wants to ride with greater speed.

The same bike can fit both the heavy and lighter rider, but I would have the bike refit and adjust the seat & stem to keep up with the changing rider.

When i first started riding, I had a much more upright position. 60lbs later, I flipped my stem and ride in a more agressive postion much more comfortably.

What about feet? Do feet swell less under hot conditions with a lower weight? Say 220 to 190?

Also, neck and shoulders. Is there less strain on the neck and shoulders on a road bike with the same lowered weight? I'm thinking the gut would throw you more firmly down on the top bar.

The core muscles, not the shoulder muscles, should be supporting the upper body on a road bike. The lower back & ab muscles will strengthen as the rider progresses. The rider should not be putting too much load on the shoulders, arms & hands. The head will strain the neck muscles to a degree, but the core muscles are key.

I'm actually looking for a less aggressive fit to help me endure longer 5 & 6 hour rides. If the rider rides more, the handlebars should not be way below the seat, IMO.

Michael

A good bike fit also has a lot to do with adjustments to the flexibility of the muscles/body - influenced a lot by the size of the belly.

This is what I thought, so with a tighter budget, it's probably best to kinda, sorta try to do the best fit they can and put the professional fit off until they lose the weight, by that time they will probably need a new bike anyway and can get it professionally fit at that time. :D

You would think that the best fit for distance would be to have the bars above the optimum saddle height, but shops don't seem to understand this, maybe because bike touring is just starting to get more traction this side of the pond.

Although bicycle tourists have been around for decades, it's been a rather microscopic part of the North American bicycle market, especially compared to the full suspension mountain bike market. It is growing though and many manufacturers have at least one model. Hopefully that will mean as dealers get more familiar with it, that they will end this silly idea that a road bar means racing only.

This is my bike before, and after 45lbs lost. Note the seat post (and change of saddle model), and handlebar position. I even changed the tires from the 1.95" Comfort, to a 1.5" Invert tread.

BEFORE:

http://i245.photobucket.com/albums/g...vigator08b.jpg

AFTER:
http://i245.photobucket.com/albums/g...vigator09b.jpg

IMO its because a person gets fit they become more limber I lost a 140 lbs so fAR AND BIKE STILL FITS THE SAME ! ymmv THOU :o)

It's interesting that you mention this. My fitter and I discussed this during a fit update. After 2000 miles, and a 30 lbs weight loss, he assumed that I wanted a more aggressive fit.

I had to explain that I needed the fit update to reduce discomfort after 4 hours of riding. We ended up raising the stem and changing to a compact bar to reduce the stretch needed to ride the drops.

Michael

Depending on the rider, the optimal "distance fit" will usually have the bar close to the level of the saddle. While cycle touring shops may not be common, there's a newfound interest in randonneuring in many areas. It might be possible to find a shop that understands a traditional rando fit, which is typically much more upright than the standard road racer position.

I've noticed that as little as 15 pounds (barely a 6% difference of total weight for me) makes a difference in how my bike feels.

[QUOTE=CliftonGK1;9011590


I've noticed that as little as 15 pounds (barely a 6% difference of total weight for me) makes a difference in how my bike feels.[/QUOTE]

I would love to see how my bike feels after I lose 15 pounds!.. Wish I could lose 15 lol.

Hm maybe I should really check my fit on my bike again. With people mentioning as little 15 making a difference I gained about 24 sooo maybe I need to move some stuff around. :(

As I lost more and more of my gut I could reach further, get lower, and was just all around more comfortable in more elongated positions. I tried a bike at my peak of 260ish that felt terrible then. I own that bike today (langster) because it was TOTALLY different 60lbs later.

+1 on lengthening of the legs... I liked to believe I was having late life growth spurt, but the reduction of the built in seat pad sounds more plausible.

I think fit for randonneuring and touring are probably similar, equal or slightly above the saddle, rather then the 4-5" below that seems to be common in racing. People forget that in racing the ideal is to be as fast as possible, so comfort, durabilty and economics all take a back seat if it means a .05 second faster finish even if the race is 100km or more. There are differences though, between a bike that simply needs to go 200km over a 10 hour period and a bike that needs to go 75km a day for 10 days straight without any bigger problem then a flat tire or two. That could also affect fit to some degree.

The idea behind the original posting though is should a person new to cycling who is 100lbs overweight, get a professional fitting now, or wait until they can reduce the weight, then get the fitting.

I had a professional fitting last year. I had been riding a comfort bike, had dropped from 245 to 225 and wanted a faster bike suitable for long distance work. I'll do my first century next weekend.

I think a new rider who is heavy should get started with an upright bike like a Giant Cyress and wait until this bike no longer satisfies the user before considering a fitter. The heavy user should test ride a variety of bikes from better LBS that will assist the user.

I would not invest in a professional fitting, and the better, more expensive bike that will result until the rider really knows thier needs.

The fitter will need to know "what kind of riding and use do you (the user) want from the new bike?" The fitter will also expect better road shoes with cleats and will not recommend a low cost upright bike. They are good with fitting road, touring, TT & tri and will fit a cyclocross bike when asked. Thier skills are not very applicable to new riders.

Michael

as i lost weight i was able to get lower and lower as my stomach got smaller.

Am I being fair when I say that minor adjustments to you fit should not be considered a static thing, ie we should think of the fit as a dynamic thing that requires continual fine tuning.

with this in mind, I would have to say that we need to get good at listening to what our bodies are telling us.

If you are experiencing a certain type of ache or pain, please - by all means - try something immediately to relieve the stress on that joint or muscle.

just my 2 cents worth. I hope this helps.

best of wishes to you

ST

I've lost 100 lbs but about 60 in the last year or so. I've never felt the need to buy a different sized bike based on the weight loss.

John

Except we weren't talking about a different sized bike. ;) We were talking about adjusting the setup to a different fit as you lose weight. The new bike only came into it as a side effect of when the poster decides they want one, and it may be the best value to wait til then to get that pro fitting done.:D

+1

same for me, but it made a difference after only 15lb (220>205).