After traveling with my bike for Hell’s Bellxs and seeing Enforcer tease a S&S Coupler version of the steel BD, I have been thinking a lot about how much bike weight affects your game. I currently ride a Koncept v3 and find that speed is a huge part of my game. Does the few pounds of difference between a steel vs aluminum frame change your overall speed, acceleration, and agility meaningfully?
yes , but there is no limit on the amount of polo bike you can own 
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It is a very large question and it can’t be replied without deep scientific approach and an exact comparison.
How you feel on a bike for a big part depend on you (flexibility, strength, and your feelings between day a and 2 months later when you try another bike), another big part is physics.
I will try to make things simple while keeping a scientific approach:
There are thousands of steel nuances and same for aluminium, there are many different way to make the tube and same to make a frame. You imagine the different combinations of each and here you are, in front of an infinite cloud of solutions.
However, considering most bikes are made of aluminium 6061 and steel bike are made of medium strength steel, and considering our practice (bike polo stress the bikes quite a lot more, due to frequent accidents and a lot more repetition of acceleration and deceleration) 2 key parameters between the 2 materials according to me:
- related to strength (capacity of the frame to survive a sudden stress⛓️💥), aluminium is way weaker (about 2 to 3 times less). The design and manufacturing guarantee the strength of the bike, because the designer of the bike has to use way more material (bigger and thicker tubes). That explains why, despite a density 3 times lighter, aluminium bike aren’t 3 times lighter.
- related to fatigue (durability of the bike
), steel can be designed technically to have a endless life. Of course in practice, it depends of 1-the actual design , 2- the quality of the manufacturing (quality of the tube, the welding) and 3- the use. However, regardless how good this 3 parameters are for a given bike, if it is in aluminium, it WILL break. For steel, there is a chance it won’t.
There are other things, like:
Stiffness (comfort 
and power transmission 
), steel is way stiffer (about 3 times), however the bigger tubes used with aluminium usually compensate. I personally think bike design has bigger impact than purely material.
Aluminium is more brittle and less tough. It means it gives less sign of stress before breakage, it deform less for example, and resist less to the propagation of a breakage. (About 2 times less performant than steel)
And finally, steel is a lot less energy intensive to produce and recycle (about 4 times !). So steel is actually nicer for our planet 
however, the best bike for the planet is not the bike you buy, but the bike you keep.
Probably you understand I’m pro steel 
Now, if I come back to your question.
Bike polo is indeed a lot about acceleration.
Physically, at THE moment you press your pedal, your acceleration is equal to the sum of the force you apply divided by “your” mass.
Keep in mind, “your” mass is actually the total mass, you + the bike.
In my case, let’s say 75kg + 10kg of bike, 85kg total. So actually 500g gained on the bike make my system go from 85 to 84.5, so
3% gain.
Also to keep in mind, the useful force here is the force applied by the tire on the ground to make you move forward. It is linked to the force of your feet on the pedals but this link has to be clarified.
The force on the pedal goes through a lot of losses: transmission efficiency, bike deformation, wheel and tyre deformation but also, last but not least, the lever effect of your crank, which depends on its angular position. You easily understand that if you press the pedal when it is in its bottom position, there is no gain for you to move forward.
Finally, this was at THE moment you press, it is a static thinking. Now if you want to consider the whole dynamic, from the moment you press the pedals because you want to go towards the ball till the moment you reach it before your opponent, we have to consider inertia.
Your inertia (of you + the bike) depends the mass, but not only ! Your wheels aren’t simply sliding to the ball, there are rolling, so they are rotating.
And inertia of a rotating object is related to mass and radius, squarred!
This explains why, everything else equal, 26" bikes tends to be quicker than 28". (Double effect of less material on the rim because smaller + smaller radius)
So, in conclusion, IMO:
- steel is the answer, specially if you don’t already have a bike.
- Before talking about 500g difference between 2 bikes, look at the total weight, including your own weight. (In other word, have a pee before a game might give your the same gain )
- Before talking about 500g difference, look at your physical condition, there is probably a margin to push harder on the pedal (I recommend explosivity training rather then power) but also to your pedaling technics, specially pedaling efficiency. (A “bad” cyclist can have an efficiency of about ~30%, means he is loosing 70% of his energy into deformating the bike, while a pro has about ~60%)
This goes with explosivity, because THE 100% moment is when your crank is horizontal. - Finally, eventually reconsider your choice of 26 or 28, and invest in light rims and tyre! It is a big challenge in bike polo because they take a lot of damage so we can’t simply go for road race rims. But a few grams won here will make a big difference because its effect is multiplied by the radius! Investing in a hub for marginal weight gain of few grams is not the way. (It is in the centre of the wheel, no radius, so no inertia gain), there are better place to put your €. (But it worth spending some money for bearing and freewheel quality)
By the way, except the last advise, they are all free
So, my answer is yes, it will change, that’s physics, but it is marginal and they are most probably other ways to compensate the additional few hundred grams, especially if it allows you to play more polo (I hope not with more flights)
Hope it is understandable .
Cheers.
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i always heard the oposite , that alu is stiffer than steel ? did you got mixed in your explanation
also aluminium has a shorter cycle of fatigue stress , just like aluminium bolts snap after tighetning them on and off over and over again , you can suppose that an aluminium fork and frame will eventually snap after repeated front braking stress
alrhoug my steel frame snaped at 3 different places for the same reason , but it was very light (9/10kg for a L bike)
also you specifically compare enforcer and koncept they have very different geo so that will imoact your game way more than the weight change
thats why in the end i recomand you to buy both , but couplers are a bit over rated ( you need to check if they are tight all the time and carry that extra tool)
No no, no mistake. A Google search to find the elasticity of both steel and aluminium will show it.
But elasticity of material and elasticity of a object it different.
That is why, when it come to material, test engineers will test with the same geometry.
Aluminium frame are indeed usually stiffer because it is needed to compensate a weaker material, at equal frame geometry, the only things left to make a strong enough bike is to increase the material, so tube diameter and/or thickness. Example, for a given steel frame with 0.8mm tube thickness, if you want to make the same bike in alu, you’d need a tube of~2mm to guarantee the same strength to your customers.
However, the flexibility of a tube depend on the material elasticity and the diameter power 4 !
Then if you reduce the material stiffness by 3 but multiply the geometrical factor but (2/0.8)^4, that’s 40/3 = 13 times stiffer. (This is overly simplified but the idea is here)
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now tell me everything you know about titanium , carbon and polyethylene plastics
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Thank you @OGxBENJI and @Lucas.bxl. Certainly a lot to learn and understand about material and its effect on a polo bike. I started on a steel bike and hated it, however I believe it was because of poor geometry and less than optimal components. Now I’m on an aluminum bike, and I like it a lot but that is likely coming from a combination of the weight + the geo being correct for the sport. I’m coming to the conclusion that I just need to try stuff out until I find what works best for me.
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yeah trying is the only way ! hop on any enforcers your size and with similar stem/ saddle setup than you.
better yet if you have a really good friend with one ask him if you can borrow it and put your usual handlebars and stem on it : stem and handlebars length can make a lot of difference
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For titanium, well, I should dig it, put it is most probably a better choice mechanically, but not budget wise and footprint wise.
There could be a similar result (in strength and weight) to use high strength steel (high alloy steel) but that is for the moment quite expensive and mostly monopolized buy the industries where it makes more sense (specific part of vehicule’s frame, electric motors etc…).
Somehow titanium is more niche, but more accessible for small industries, I think 🤷 (similarly, smaller industry don’t get top notch titanium probably)
For polymers or composite, it becomes more complex.
For exemple, I didn’t mentioned so much about geometry (for example when we talk about stiffness, we should be talking in what direction, and the shape of the tube, and for non homogène materials, grain/fibers directions becomes important).
And, if one big gain with polymer or composite is the mass/strength ratio, the other big one is the freedom of shape…
Verify useful when talking about applications where mass and strength are key performance, is this:
http://www-materials.eng.cam.ac.uk/mpsite/interactive_charts/strength-density/basic.html
How to read ? You have to imagine radial line with center on the bottom left.
Everything on a line as the same perf.
For example the “oak across grain” is similar as the polymers and glass family. (Glass is more dense, also stronger, so you would use less material for the same strength…ending up in a similar weight as the wooden bike)
And, for example, the line reaching the top of the woods family is unbeatable (However there are others challenges 
like connection, durability against water/salt etc…)
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