What does the wrong size bike feel like?

[Azee]

I am about to purchase my first bike as an adult.

When I test ride a bike, how can I tell which size suits me, and what does the wrong size feel like?

[Duck!]

A bike that is too large will have you stretching uncomfortably for the handlebars, and when standing over the top tube of the bike (both feet on the ground, off the saddle) it'll be uncomfortably close to your sensitive bits - you don't want that in an emergency dismount!

A bike that is too small will feel cramped; to the point of feeling like you're going to fall over the front of the bike if it's really undersized for you.

[Azee]

Thanks Duck,

Do a couple of centimeters make such a difference though?

[reefer]

Yes they do, if you start to rack the hours or kilometres up.
Having a frame the incorrect size will most likely cause substantial damage to you. As you can imagine, cycling puts repetitive strain on your body, carried out for hours a day will most definitely injure you.
Take the time to read as much as you can about different perspectives on bike types and fit. Understand how your body fits a bike frame.
Then, try out as many bikes as you can for at least a few hours each. At least 2 bike stores in my area will allow overnight or extended trials.

A bike thats fit for purpose and fits you well is the Number 1 priority.
(I ride for fitness and don’t race, but can ride up to 4 hours a day. Comfort is important to me as it brings efficiency)

[toolonglegs]

Plug you measurements into an online calculator ... compare that to what the shop is recommending.
Don't stress over it too much... Saddles move up and down 10-25 cms and forward and back 5-10 cms ( depending on seat post ) ... stems on a road bike can be anywhere between 60-150mm long ( 80-120 is normal'ish range ) .
I have never test ridden a road bike in my life.
Personally I can ride a 58-63cm bike quite happily... some days at work I get given a hire bike for 6 hours riding... maybe I am just not fussy

[cancan64]

I am 183cm tall and have a 54 a 56 and a 57 and for 1 -2 hr rides cant tell that much difference although over 4hrs I can...a good fitting is well worth it

[Nobody]

On the other hand, if you're short, then you're more likely to be sensitive to frame size. This is because it's difficult to get a 700C frame that is small enough and smaller differences in outright lengths can make a bigger relative difference. Then there is the intrusive toe overlap problem with the front wheel and a compromised braking position because the bottom bracket to front hub (center to front) is short.

[bychosis]

I'll second (or third) the opinion that for shorter rides the fit is not as critical, but it certainly helps to be pretty close. I bought a frame to make a fixie and was dissapointed when I measured the size finding it 2cm larger than the bike i was riding comfortably. Once I tried it out it was OK, it's not a long distance bike by any means, but a size up or down can often work as a last resort.

Have a look here: http://www.competitivecyclist.com/Store ... orBike.jsp

[ohexploitable]

i have two roadies, one has a 55cm tt + 90mm stem, the other has a 53.5cm tt + 120mm stem

both are set up the exact same, i.e. identical saddle-BB height, identical saddle setback, identical saddle-handlebar length, identical saddle-handlebar drop etc.

both feel the same (position-wise)

i don't see any reason why you can't have a bike that's a few cm's off and compensate with appropriate stem/seatpost adjustments

[Gordonhooker]

You know it is too small when you feel cramped on the bike and too large when you have to stretch to grab the handlebars and your feet can't touch the ground comfortable.
I had an issue trying to work out the best size for me initially because I am short in the legs and long in the trunk and it seemed I was on the cusp of a small to medium frame, for my fixie I ended up going medium and a slightly higher angle on the stem, and flipped my bullhorn bars up and now it fits like a glove.

[tron07]

I got small hands, feel hard to grab the brakes suddenly if my hands are not ready at the brakes level, ie if something jumps in front of me.

[silentC]

how can I tell which size suits me

I wish someone would tell me. I've been riding the same bike for years and I have had different people tell me it is too big AND too small for me. Just call me Goldilocks...

[RonK]

how can I tell which size suits me

I wish someone would tell me. I've been riding the same bike for years and I have had different people tell me it is too big AND too small for me. Just call me Goldilocks...

Since there is a least a consensus that it is the wrong size for you, then the wrong size must feel like the bike you're riding.

[Duck!]

I got small hands, feel hard to grab the brakes suddenly if my hands are not ready at the brakes level, ie if something jumps in front of me.

It took a while, but component manufacturers have finally realised that there are different sized riders, so most brake levers these days have some kind of reach adjustment mechanism.

[rogerrabbit]

I suggest getting a bike shop to do a proper bike fit for you, but be careful you don't get fitted up by some young gun who thinks a racing position is the only position. (racing will be a slightly different position to general fitness riding, but given you are not sure on size, I am assuming you are not racing, yet...)

Top tube and seat tube lengths are key aspects, but seat to bar drop is also important. A smaller frame with a short head tube is going to give a pretty big drop to the bars, which also increases the reach by the way. Some racing frames are going to be stiffer, sharper handling and perhaps more harsh as far as transmitting shock to the rider from the road. Other frames are going to have a more relaxed geometry, but may put you in a more upright position with a shorter distance to the bars. This can suit a lot of riders, and I would guess that newer riders will often prefer a more upright position, as May some older riders that are less flexible. I personally prefer a more racing position, even for general riding, but I have been on racing bikes for nearly 40 years. I find I can fit frames from 58 to 62cm in the top tube, but largely compensated for by seat and stem and bar choice and adjustment. I struggle with too much bar drop, and with bars that are too narrow. I would say bar width is a key issue for me. Finally I want a frame that has good balance. This could be a racing or a touring frame, but the bike should be neutral and stable in all circumstances. If it flops into a turn or feels unnatural, then the geometry may be off (usually fork rake to head angle balance in my experience).

Crank length - I ride from 165 to 175 on different road bikes, and I really cannot tell the difference.

After that diatribe, try riding lots of different bikes, and try to get a sense of what works for you, and what doesn't.

Roger

[cage]

The OP has already put a deposit down on a bike. Details here.
viewtopic.php?f=9&t=78945&p=1177427#p1177427

[tron07]

I got small hands, feel hard to grab the brakes suddenly if my hands are not ready at the brakes level, ie if something jumps in front of me.

It took a while, but component manufacturers have finally realised that there are different sized riders, so most brake levers these days have some kind of reach adjustment mechanism.

I will research on this to see if I can play with it or not, else will get the shop to adjust on my first service.

[Six13]

seat to bar drop is also important. A smaller frame with a short head tube is going to give a pretty big drop to the bars, which also increases the reach by the way.

I have a 58 and thats the problem I have with it. I measure the nose of the saddle to the back of the brifters, and also the vertical drop from nose of saddle to top of brifters. While this might not be scientifical, seems to work for me.

[rodneycc]

I got small hands, feel hard to grab the brakes suddenly if my hands are not ready at the brakes level, ie if something jumps in front of me.

It took a while, but component manufacturers have finally realised that there are different sized riders, so most brake levers these days have some kind of reach adjustment mechanism.

I will research on this to see if I can play with it or not, else will get the shop to adjust on my first service.

Or get the shop to rotate the bars backwards a little more so the hoods come back your way a little more. I had similar problems with my hands.