Paging The Oracle. . .or Slowman. . .or Gerard. . .or anyone who knows about this bike stuff. . .

Here's another question for those of you with two scales at home- what is the actual weight distribution on your bike? Does it differ between your road bike and your tri bike? By how much?

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"People think it must be fun to be a super genius, but they don't realize how hard it is to put up with all the idiots in the world."

I don't know the exact weight distribution on my bikes but almost all tri bikes will have a more forward weight distribution than a road bike once the rider is down on the aerobars.

As for how much it affects handling, that is highly individual. For years I rode a Softride with the seat angle at about 82 degrees. The effective top tube length was about 51.5 cm even though it was a size large. A very large portion of the weight was over my front wheel but *I was used to it* and didn't really mind. When I ordered a custom frame I was able to specify the same seat angle but with a longer top tube (and therefore a longer front-center measurement). The longer top tube got much of the weight off the front wheel while keeping my position about the same, and the so the custom bike handles much better.

For this reason, I like to go with a large frame size and short stem on my tri bike. Conversely, I like a small frame and long stem on my road bike.

How much attention to this issue is given by most professional fitters?

In all the fittings I've had done, nobody ever addressed weight distribution. How much can I alter it before I start to notice degraded handling?


I don't know the answer to this, but the altered weight distribution will manifest itself in many different ways. For example, on my tri bike significantly more than 50% of my weight is over the front wheel. The "handling" seems good, and I'm used to it, but other wierd and wonderful things tend to happen. For example, if I'm cruising along and I'm really scooted forward in the saddle and I hit I bump that I didn't see or wasn't expecting, the rear wheel will lift off the ground sometimes. This wouldn't be so bad in and of itself, but if the wheel lifts while one of my legs is in the 3 o 'clock position the force on the pedal will cause the rear end to swing out slightly to the opposite side while the wheel is momentarily in the air. Not a particularly reassuring sensation.

"My understanding is that the ideal weight distribution on a bike is 50/50."

depends. if you're on a road race bike road race set up, no aerobars, riding with your hands on the hoods, more like 60/40 with the largest part of the weight on the rear. hands on the tops, a little more on the rear. hands on the drops, maybe 55/45.

aero bars, steep seat angle, saddle nose over the BB, yes, 50/50. unfortunately, if it's a road bike retrofit, can be closer to 40/60.

the point of mandaric's DE geometry (named for a devastatingly good looking guy) is to have very steep geometry, yet maybe 52/48 weight distribution. the operative difference is long front/center achieved by touring front end (72d head angle, 48mm offset, more/less).

keep in mind that the big problem with tri bikes is the steeper angle, yes, but even more so the laying of the front of the body on the aero bars. bad weight distributions are not usually problematic until you get into trouble situations (braking and cornering on descents, stuff like that).

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Dan Empfield
aka Slowman

Dan correct me if I got it wrong but you can see examples of the long and slack front end as you described on Paul Levine's site (www.signaturecycles.com). Go to the gallery page, almost every tribike seems to be configured in that way. Also note extended head tube and arm rest set relatively high in relation to the seat position. I susepct a perfect MOP set up configured with comfort in mind.

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Simple Simon
Where's the Fried Chicken??

"I suspect a perfect MOP set up"

i'm speaking more about a nice handling front end on a rather low-in-front, race-specific, podium-winner style bike.

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Dan Empfield
aka Slowman