What is the most stable triathlon bike on the market now?

I know we’re usually interested in speed or comfort, but my wife is looking for a new tri bike to replace her older Felt S22 and all she wants is something that feels stable and safe to her. She feels that she does not have a good sense of balance and that spending time worrying about staying upright on the bike is time that could be better used putting power down, even if the bike itself may not be the fastest out there. It’s hard to tell this from online reviews, since stability is not something the reviewer usually focuses on, but obviously I would stay away from bikes described as “twitchy” for example. She is 5’4" so would typically go with a 50cm or so frame - I think the smaller frame size would typically make a bike stiffer and possible less stable, so that might be part of the issue. Also, her Felt has 650c wheels - maybe 700c wheels that no doubt come on any newer bike would provide a more stable feeling to her?

Thanks

Bikes handle well when they are the correct size and the rider has the correct fit and weight distribution. When the saddle is comfortable enough you are not trying to escape it and the aerobars and particularly the elbow rests have a comfortable shape and padding. Correct air pressure in the tires can help as well. In general, buy the longest bike you can that is still low enough. Finally, learn to RELAX as you ride. Nothing will upset the handling of the bike so much as a tense rider.

The inherent handling differences between most tri bikes is paltry or even nonexistent in comparison to careful consideration of the above factors. You will not make reasonable assessments of handling differences by test riding a bunch of different bikes because 1. They don’t really exist and 2. The handling of the bike will be affected more by the differences in set up, as compared to the riders ideal position.

The Felt IA has to be on that short list. The thing is intentionally designed to go in a straight light. The sucker handles like a river barge. I sweat bullets going around sharp corners at speed. On the other hand, crosswinds mean nothing to me on that bike.

Bikes handle well when they are the correct size and the rider has the correct fit and weight distribution. When the saddle is comfortable enough you are not trying to escape it and the aerobars and particularly the elbow rests have a comfortable shape and padding. Correct air pressure in the tires can help as well. In general, buy the longest bike you can that is still low enough. Finally, learn to RELAX as you ride. Nothing will upset the handling of the bike so much as a tense rider.

The inherent handling differences between most tri bikes is paltry or even nonexistent in comparison to careful consideration of the above factors. You will not make reasonable assessments of handling differences by test riding a bunch of different bikes because 1. They don’t really exist and 2. The handling of the bike will be affected more by the differences in set up, as compared to the riders ideal position.

This ^

Last year I went from a too-small 51cm Cervelo P2SL to a 54cm P2K (pretty much the same bike other than size and some minor weight differences) and the 54 is SOOOOO much more stable handling and nicer to ride on fast downhills.

A disc brake tri bike that can run 28 mm tires could help out a good bit if her fit is adequate and she is on the right size bike.

Some good points, it’s funny because we are always taking about pad xy etc but the first two measurements I look at on bikes are FC and Bb drop.

Maurice

The Felt IA has to be on that short list. The thing is intentionally designed to go in a straight light. The sucker handles like a river barge. I sweat bullets going around sharp corners at speed. On the other hand, crosswinds mean nothing to me on that bike.

i dispute the notion that bikes designed to go in a straight line are the most stable or easiest to handle.

The inherent handling differences between most tri bikes is paltry or even nonexistent in comparison to careful consideration of the above factors. Is this valid? I thought that head tube angle and fork rake dramatically affected handling?

i dispute the notion that bikes designed to go in a straight line are the most stable or easiest to handle.I meant that more metophorically than literally. I’m not sure even how to describe handling, because people probably have very different and personal definitions of stable or easy to handle.

I raced criteriums very long ago. I like responsive road bikes that can corner or change a line in an instant. Some people may call that hard to handle or unstable. But to me it is easy to handle. My IA16 is the opposite of that. Mountain switchbacks are a careful negotiation. And, I often come very close to clipping the cones in one-lane 90 corners in triathlons. But, I can also get blasted by a 30 MPH crosswind and barely move a few inches, while my friends on a Cervelo P2 and P3 got blown into barriers and crashed.

Most tri-bikes have fairly similar head angles and fork rake (it’s the resultant trail dimension that’s important).

The inherent handling differences between most tri bikes is paltry or even nonexistent in comparison to careful consideration of the above factors. Is this valid? I thought that head tube angle and fork rake dramatically affected handling?

Probably 90+% of current tri bikes have a head tube angle within 1° of 72°.** **How much do you think that variation affects handling?

http://garywolff.com/kerry_training_wheels.jpg
.

Probably 90+% of current tri bikes have a head tube angle within 1° of 72°.** **How much do you think that variation affects handling?I do not know. SuperDave commented here several times that Felt intentionally designed the IA to have this version of stable handling, and he referenced other more nimble tri-bike designs as contrast. My IA16 has a 72° head angle. A Cervelo P2, which I thought was known as a more nimble bike has a 72.5° head angle. Neither site publishes rake, which also affects handling.

My road bike has a 73° head angle, and it is super quick and nimble. So, just by that simple range, a P2 is half way between my river barge IA16 and my crit-capable road bike. So, maybe 0.5° head angle makes a huge difference.

Probably 90+% of current tri bikes have a head tube angle within 1° of 72°.** **How much do you think that variation affects handling?I do not know. SuperDave commented here several times that Felt intentionally designed the IA to have this version of stable handling, and he referenced other more nimble tri-bike designs as contrast. My IA16 has a 72° head angle. A Cervelo P2, which I thought was known as a more nimble bike has a 72.5° head angle. Neither site publishes rake, which also affects handling.

My road bike has a 73° head angle, and it is super quick and nimble. So, just by that simple range, a P2 is half way between my river barge IA16 and my crit-capable road bike. So, maybe 0.5° head angle makes a huge difference.

River barge is exactly what I was going for.
-SD

Last year I went from a too-small 51cm Cervelo P2SL to a 54cm P2K (pretty much the same bike other than size and some minor weight differences) and the 54 is SOOOOO much more stable handling and nicer to ride on fast downhills.

I was the other way around. I had P2 54 size and it was like a big boat. Went down to 51 and oh boy, what a relief! It’s much easier to ride and handle now.

Probably 90+% of current tri bikes have a head tube angle within 1° of 72°.** **How much do you think that variation affects handling?I do not know. SuperDave commented here several times that Felt intentionally designed the IA to have this version of stable handling, and he referenced other more nimble tri-bike designs as contrast. My IA16 has a 72° head angle. A Cervelo P2, which I thought was known as a more nimble bike has a 72.5° head angle. Neither site publishes rake, which also affects handling.

My road bike has a 73° head angle, and it is super quick and nimble. So, just by that simple range, a P2 is half way between my river barge IA16 and my crit-capable road bike. So, maybe 0.5° head angle makes a huge difference.

My NP2 is somewhere between my road bike (Orbea Diva) and my Felt DA.

The trail on the DA is 65mm, NP2 is 59.5mm and the Orbea is 56mm

There is definitely a difference between them

A disc brake tri bike that can run 28 mm tires could help out a good bit if her fit is adequate and she is on the right size bike.

Wider tires are a good idea in general – disc or rim brake. You just need to make sure you have a newer bike w/ clearance in the forks and rear. And you’ll have to get the brakes adjusted accordingly. I bought a set of HED Jet Plus wheels and threw a 25 mm tire on and it really helps with comfort going in a straight line and I have much more confidence cornering, and there’s no aero penalty with a wider tire on a wider rim.

It seems ‘trail’ has already been covered. A 650 wheel can have less trail than a 700 if using geometry specific to the 700. I have no idea if your wife’s Felt was ‘corrected’ to increase the trail to that of a typical 700 wheel.

I think a lot of people would agree on the point about going as long as possible (reach or front center) while being at the front end height she needs. Long and low is big in mountain bikes for stability, not sure why that couldn’t extend to tri bikes.

On an n=1 qualitative level, I had a frame replaced after a warranty issue and asked for one size up from what my (terrible) fitter sold me on before. It was ~20 mm longer in reach and ~20 mm taller in stack. All I did was swap the stem for something 20 mm shorter and knock out the two spacers I had below. It was a world of difference.

I hope we start seeing frames get lower bottom brackets to go with shorter cranks. Riding 160 cranks on a frame with the same height as my 175/172.5 road bikes feels weird. I swear I notice the higher center of gravity.

If your wife is 5’4", I would recommend sticking with a smaller bike with 650b / c wheels if stability is a concern.

A more stable bike usually means

  1. Longer stem (slower steering)
  2. Steeper head angle
  3. Longer trail → trail is determined a combination of head angle and rake, see http://yojimg.net/…_tools/trailcalc.php
  4. Lower BB height
  5. Weight distribution on wheels (rear center vs. front center)

1: Your wife is on the shorter end of the 700c wheels, which means she’ll probably end up with a fairly short stem, so steering will be quick if she’s riding it. She might have her elbow right over the steering axle, which doesn’t sound very stable to me (I am less confident on that, so have others chime in?)

  1. small sized bikes 700c wheels tends to have steeper head angles, so points to 700c here

  2. Small bikes with 700c wheels also tend to have more rake to avoid toe overlap, this reduces trail even though those bikes tend to have slacker head tubes. For example, Felt 48 /51 have less trail than size 54 and up even though the head tube is slacker (albeit not by much).

  3. Some smaller sized 700c bikes achieve lower stack by having a higher BB height (e.g. BMC, Orbea).

  4. 650c bikes can have shorter rear center, resulting in less weight load on the front wheel

On top of it, a 650b/c bike will likely fit her better. So i think that’s the better route. options are limited though (I think only Premier and Canyon offers those options) and race wheel choices even more limited. So pick your poison.

(calculator above also have explanation and calculation of wheel flop, etc.)

If your wife is 5’4", I would recommend sticking with a smaller bike with 650b / c wheels if stability is a concern.

A more stable bike usually means

  1. Longer stem (slower steering)
  2. Longer trail → trail is determined a combination of head angle and rake, see http://yojimg.net/…_tools/trailcalc.php
  3. Lower BB height
  4. Weight distribution on wheels (rear center vs. front center)

1: Your wife is on the shorter end of the 700c wheels, which means she’ll probably end up with a fairly short stem, so steering will be quick if she’s riding it. She might have her elbow right over the steering axle, which doesn’t sound very stable to me (I am less confident on that, so have others chime in?)

  1. Small bikes with 700c wheels also tend to have more rake to avoid toe overlap, this reduces trail even though those bikes tend to have slacker head tubes. For example, Felt 48 /51 have less trail than size 54 and up even though the head tube is slacker (albeit not by much).

  2. Some smaller sized 700c bikes achieve lower stack by having a higher BB height (e.g. BMC, Orbea).

  3. 650c bikes can have shorter rear center, resulting in less weight load on the front wheel

On top of it, a 650b/c bike will likely fit her better. So i think that’s the better route. options are limited though (I think only Premier and Canyon offers those options) and race wheel choices even more limited. So pick your poison.

N=1, but…
I am also 5’4", and moved from a 47cm Slice with 650c wheels to a 51cm IA with 700c wheels and the difference was absolutely night and day. I was certain that I wanted 650’s (not least because of toe overlap issues I have with both my CX and road bikes) and really had to be sold on the Felt, but boy, I love that bike. It is river-barge stable, and I feel safe and secure even with my race wheels in the wind. I was so frightened of the Slice that I rode it on the trainer for four years and never raced it once. I cannot advocate strongly enough for the Felt.