Drop that stem ?

[Doyleyburger]

After experiences and opinions here really.

As I'm getting more comfortable on my bike iv decided to drop my stem by a couple of spacers (approx 10mm).
Not really a competitive cyclist but must admit I'd like to improve some areas of my riding. Feel ok on climbs but would like to improve on flat sections of road. Been told before that riding on the drops more could benefit your speed by as much as 2mph? ???..... possibly BS but that's what iv heard anyway.
I ride on the drops as much as I can these days anyway, but wondered if I might see any improvements with the stem drop ?
Thanks

 

[MichaelW2]

Aerodynamic drag is the largest drag force at high speed. 80-90% of aero-drag is due to the rider. If you are riding fast, the only way to ride faster is to improve aerodynamics. 2mph seems quite reasonable.
To reduce aero-drag you need to reduce your frontal profile, making it lower and/or thinner. Drops and clip-on aerobars can help you do this.
Position your bars so your normal cruising position is on the brake hoods. Pick a bar with a comfortable depth of drop.
Drops cannot in themselves make you aerodynamic, it is the way they position your body. Any other bar that keeps you in a similar position will be as effective. Drops give you a variety of different hols for different situations.

 

[ColinJ]

Suck it and see?

I had to go the other way and flip my stems to get the bars higher on two of my bikes. Even after that, I don't spend much time on the drops. Lack of flexibility in my old age, and I still have a small roll of fat round my waist which gets in the way!

If you are comfortable spending lots of time on the drops then maybe you can get away with lowering your bars. I would be tempted to just do it by one spacer first. If that feels good, then try removing the second one later.

Tip: Don't decide that you like the lower position and immediately hack a cm off your steerer - if you change your mind later then you would be stuffed! Move the spacer(s) to above the stem.

 

[GrumpyGregry]

Some marginal gains are more marginal than others.

 

[GrumpyGregry]

Aerodynamic drag is the largest drag force at high speed. 80-90% of aero-drag is due to the rider. If you are riding fast, the only way to ride faster is to improve aerodynamics. 2mph seems quite reasonable.
To reduce aero-drag you need to reduce your frontal profile, making it lower and/or thinner. Drops and clip-on aerobars can help you do this.
Position your bars so your normal cruising position is on the brake hoods. Pick a bar with a comfortable depth of drop.
Drops cannot in themselves make you aerodynamic, it is the way they position your body. Any other bar that keeps you in a similar position will be as effective. Drops give you a variety of different hols for different situations.

.2mph seems more likely for a Cat 5 rider. 2mph would be a 10% avg speed gain for most of us. If the OP really wants to go aero he should get a recumbent.

 

[Dogtrousers]

Tip: Don't decide that you like the lower position and immediately hack a cm off your steerer - if you change your mind later then you would be stuffed! Move the spacer(s) to above the stem.

When I bought my bike the chap at Spa looked at me, looked into my near future, and wisely left me a couple of spacers at the top to allow for the ageing process. Kind of like buying a kid clothes a bit big so they can grow into them.

 

[GrumpyGregry]

Smart fella that chap at Spa.

 

[Doyleyburger]

I would be tempted to just do it by one spacer first.

After dropping it by 2 and putting bike away I immediately got it back out and reduced it to one spacer.
Thanks tho, probably the best way to go

 

[Doyleyburger]

Aerodynamic drag is the largest drag force at high speed. 80-90% of aero-drag is due to the rider. If you are riding fast, the only way to ride faster is to improve aerodynamics. 2mph seems quite reasonable.
To reduce aero-drag you need to reduce your frontal profile, making it lower and/or thinner. Drops and clip-on aerobars can help you do this.
Position your bars so your normal cruising position is on the brake hoods. Pick a bar with a comfortable depth of drop.
Drops cannot in themselves make you aerodynamic, it is the way they position your body. Any other bar that keeps you in a similar position will be as effective. Drops give you a variety of different hols for different situations.

Thanks
Good advice

 

[GrumpyGregry]

Seriously @Doyleyburger I'd gradually drop it, in stages, to as low as I could get it, beer belly and lower back/hip flexibility permitting, and then move it up one spacer or so. You may find you need to tip the nose of the saddle down a shade, and you may also find you need to tweak the rotation of the bars and the position of the hoods, if you use them. But make any changes in small increments, try them for a bit, and then make next change.

 

[MichaelW2]

.2mph seems more likely for a Cat 5 rider. 2mph would be a 10% avg speed gain for most of us. If the OP really wants to go aero he should get a recumbent.

This is a wind tunnel test of std road bike vs time trial aero setup using a champion TT rider. Result: increase in sustained speed from 40km/hr to 44km/hr at same power output. Lesser riders can expect lower gains.

 

[GrumpyGregry]

This is a wind tunnel test of std road bike vs time trial aero setup using a champion TT rider. Result: increase in sustained speed from 40km/hr to 44km/hr at same power output. Lesser riders can expect lower gains.

Which is what I wrote.

 

[bpsmith]

The gains available depend on the wind speed in my experience. If it's a light wind, then there's a marginal gain but if it's a really strong wind then it's possible to gain 2 to 3 mph over what you are doing sat upright.

It has been suggested that you can actually get more aero by using the hoods with your forearms horizontal btw.