Would reducing UCI bike weight limit (significantly) favour lighter riders?

If they reduced the UCI bike weight limit by, say, 1kg, would it have a noticeable effect on relative performance? (ie given the greater watts per kilo increase for smaller riders)

What if they made it a proportion of rider weight so smaller riders ride lighter bikes? Would this be fair?

Not really. W/kg are measured without equipment - so they stay the same. Sorry, couldn’t resist the smart as answer ;). I know what you mean with your question.

Still a hard no from me. No significant favour for lighter riders. 1kg UCI weight limit reduction is somewhere between 1-2% reduction of the total system weight of rider and equipment. Weight primarily matters uphill. The force the riders have to fight against most of the time is - besides on steep climbs - air resistance. So the weight difference doesn’t matter that much in the big picture. Of course it matters on the top of a mountain state in a GC battle.

Additionally it’s not like heavy pro riders weigh 200kg. So the proportional difference is probably not that big either.

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It would give lighter riders a roughly 2-4 minute boost over the course of the Tour de France and would be a pretty massive detriment to GC riders that are around 70kg.

Roglic would be off the podium if they had dropped the weight limit by 1kg this year.

My mental model for this

60kg = 1.66% change
70kg = 1.42% change

TdF finish time = 87h21m = 5241 minutes

Time going uphill is roughly 1/3rd of total time so 5241*.3 = 1572 minutes

1572 minutes * .0024 = 3.77 minutes so I just turned it into a range


Additionally it’s not like heavy pro riders weigh 200kg. So the proportional difference is probably not that big either.


Dang dude…even NFL offensive/defensive lineman aren’t that big. Now if you meant 200lbs then yeah…I don’t think a pro rider comes anywhere close to that weight…I mean a bigger dude in that sport is what, 80kgs? I wouldn’t mind being able to get to that weight again but I like to eat still.

In other professional sports (that aren’t endurance based) being 80kg is on the small side. Sports like American Football, Basketball and Hockey for example.

I wonder if it would make that much difference in practice. For one, a climb isn’t pure watts per kilo, so that would take a bit of the .024 you’re applying to the climbing time. Probably more importantly, they don’t race at a steady wattage. Say it gives a few seconds at a steady pace up 30 minutes climb at the end of a stage. Roglic can still be in touch and still sprint away from the smaller guys at the end.

On the other hand, cumulative fatigue matters, so maybe it makes the difference between getting away and not. And maybe it makes a couple of seconds difference on days when there are bigger time differences. Or means Roglic doesn’t have enough to sprint.

Who knows! Be interesting to see what happens if the UCI do eventually lower it.

I’d like to see them have a few races where every one gets a bike that weighs 10% of their weight.

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