Did some Hard Maths On What Gives the Most SPEED Gains
Discussion
I wasn't able to find the exact numbers anywhere,just articles saying -- better, worse... which is totally useless so I did my own.
I will try to keep this short, I have 3 sheets full of calculations but this is to sum it up:
-If you ride slow around 15km/h a Tyre change from OK tyres to great tyres with low rolling resistance will give you huge gains alone,
-If you average speed is 25km/h+ a tyre change will still give a good effect, but the aero is HUGE ( You can Install TT bars on your mtb for like £15 and they will give you BETTER aero than being on drops on a Road bike + wear tighter fitting clothes + just look at your pose in mirror/reflection)
-Various ''must have'' bits/weight of the bike or the brand of the bike/your gear/bicycle type.. gives very very marginal gains, we are talking about max 1-3% gains,under 25km/h , about 5% if we are going at 35km/h+ speeds.
_________
Here are the numbers If we start with a mtb/hybrid with decent tyres and not very huge layers of clothes and change to better rolling tyres (£40-50/pair) and Install TT bars on your bike to get in good position + have a decent form and better fitting clothes
( based on a 80kg rider with a 14kg bike, they will change around 0.4-0.5% if you drop the weight of the bike by 4kg - so very marginal and not worth it)
_______
For the same W worth of effort:
Only with better tyres increase your speed from 15km/h to 17km/h /// 13% gain or from 60mins to 52mins to do the same distance.
Only with better tyres increase your speed from 25km/h to 26.5km/h /// 6% gain or from 60mins to 56.5mins to do the same distance.
With Better tyres+ TT bars+ good position From 15km/h to 19.3km/h /// 28% gain or from 60mins to 43mins to do the same distance.
With Better tyres+ TT bars+ good position From 25km/h to 30.3km/h /// 21% gain or from 60mins to 47.5min to do the same distance.
You can play around with some of the data here, https://www.gribble.org/cycling/power_v_speed.html however you will need to know the resistances on everything ( it's available if you search around).
I will try to keep this short, I have 3 sheets full of calculations but this is to sum it up:
-If you ride slow around 15km/h a Tyre change from OK tyres to great tyres with low rolling resistance will give you huge gains alone,
-If you average speed is 25km/h+ a tyre change will still give a good effect, but the aero is HUGE ( You can Install TT bars on your mtb for like £15 and they will give you BETTER aero than being on drops on a Road bike + wear tighter fitting clothes + just look at your pose in mirror/reflection)
-Various ''must have'' bits/weight of the bike or the brand of the bike/your gear/bicycle type.. gives very very marginal gains, we are talking about max 1-3% gains,under 25km/h , about 5% if we are going at 35km/h+ speeds.
_________
Here are the numbers If we start with a mtb/hybrid with decent tyres and not very huge layers of clothes and change to better rolling tyres (£40-50/pair) and Install TT bars on your bike to get in good position + have a decent form and better fitting clothes
( based on a 80kg rider with a 14kg bike, they will change around 0.4-0.5% if you drop the weight of the bike by 4kg - so very marginal and not worth it)
_______
For the same W worth of effort:
Only with better tyres increase your speed from 15km/h to 17km/h /// 13% gain or from 60mins to 52mins to do the same distance.
Only with better tyres increase your speed from 25km/h to 26.5km/h /// 6% gain or from 60mins to 56.5mins to do the same distance.
With Better tyres+ TT bars+ good position From 15km/h to 19.3km/h /// 28% gain or from 60mins to 43mins to do the same distance.
With Better tyres+ TT bars+ good position From 25km/h to 30.3km/h /// 21% gain or from 60mins to 47.5min to do the same distance.
You can play around with some of the data here, https://www.gribble.org/cycling/power_v_speed.html however you will need to know the resistances on everything ( it's available if you search around).
Edited by bagusbagus on Thursday 10th May 15:42
te.
The_Jackal said:
Surely this is all common sense which everyone knows.
Unless you are a Pro most people buy the go faster bits because they can or want to look like they are faster.
A large dump before a ride would probably cost you a grand in carbon fibre bits.
This post wasn't aimed at the Pro's who you see on TV, more at a regular commuter..Unless you are a Pro most people buy the go faster bits because they can or want to look like they are faster.
A large dump before a ride would probably cost you a grand in carbon fibre bits.
Yes it's a common sense and everyone knows that getting more aero will increase speed, how many have actually taken the time to analyse by how much at what speeds etc and exactly why? not many..
Most people thanks to advertising think they will become way faster if they switch from claris to ultegra shifters or have a new sticker on their bike or drop 200g from their bike when in fact it mostly doesn't even matters...
Load of rubbish... Like some generic simplified formula completely and correctly models all of the factors. What about the roughness of the riding surface...elevation gains, regular acceleration/deceleration, bike type, gearing.
Its total rusbish and overly simplistic
As has already been said, most cyclists know the basic methods of getting some easy gains like those listed above. As to if its 1% faster or 5% depends on the circumstances
If the avergae commuter/mtb rider wants to go faster....RIDE MORE! £0 cost...much larger gains
Its total rusbish and overly simplistic
As has already been said, most cyclists know the basic methods of getting some easy gains like those listed above. As to if its 1% faster or 5% depends on the circumstances
If the avergae commuter/mtb rider wants to go faster....RIDE MORE! £0 cost...much larger gains
Is that picture on your web site you? If so you should worry more about your position than crr - your noggin is siting up in the wind like a massive sail. Plus you have a round bottle on your downtube - instant loss of aero credibility.
Please post this over on SlowTwitch they will tear you (and your maths) to shreds.
Please post this over on SlowTwitch they will tear you (and your maths) to shreds.
I can think of a million things that I would rather do with my time than create that website linked in OP, or spend much time thinking about the science behind it
But, if it is something that floats OP's boat, good for him I say
Should anyone have a real interest in measuring aero stuff, Boardman is charging £350 for an hour in it's windtunnel with guidance from an 'aerodynamicist'
https://www.boardmanbikes.com/gb_en/boardman-perfo...
But, if it is something that floats OP's boat, good for him I say
Should anyone have a real interest in measuring aero stuff, Boardman is charging £350 for an hour in it's windtunnel with guidance from an 'aerodynamicist'
https://www.boardmanbikes.com/gb_en/boardman-perfo...
Crippo said:
Tri bars on a MTB?........ people have gone to prison for lesser crimes than that. I sometimes wear Crocs but there is no way on Gods Holy Earth that I would ever put Tri bars on a MTB
It must have been done though, or at least the question asked, because in a very short list of rules the "Battle On The Beach" race organisers specifically exclude the use of aero/tri bars on MTBs (and drop bar bikes for that matter) in their race.I took a drop bar bike this year, but last year (copying another competitor who zoomed past me like i was standing still) I tried a "more aero" aggressive position on the 5 km beach section, by riding holding the fork crown instead of the handlebars...
Tri bars would have been a safer option to be honest...Really strange trolling, pretty much the same thread as the one you've posted before:
https://www.pistonheads.com/gassing/topic.asp?h=0&...
This is one is strange in that you've actually replied to something you started.
https://www.pistonheads.com/gassing/topic.asp?h=0&...
This is one is strange in that you've actually replied to something you started.
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