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There’s an interesting mix of those using MPH & KPH and of course those using both. Is the use of MPH for the cough older generation or of a certain political persuasion?
I guess i'm lucky as i was at school all the way through the change, so loads of my text books were in imperial, lessons were in a mix, and we had all the equipment in both set ups at various points.
So, TBH, you had to be able to switch from lbs and oz to grams in your head, quickly, and many times in a day.
Then i went to work in the aero industry, which is weird as uck in that you have entire sections of the industry (merica) that is imperial, and you have to be able to align, so you've got imperial bolts slotted into precision metric holes. And imperial fasteners completely dimensioned in metric...
then i emigrated, and it's all in metric
I'm 65 this year and primarily use km/h* The only time I think in imperial is when driving a motor vehicle or on longer road
bike tours in the UK. I pretty much swapped over when the OS moved to metric.
* Not kph, obviously!
Not sure but gaining on cars easily somewhere in mid Wales fully loaded but felt stable from previous experience I would say ~ 50 mph. Had the same bike up to ~45 mph unloaded but felt much better / stable / safer loaded, except for braking of course!
On the A470 in Snowdonia heading south between Cross Foxes Inn and Mallwyd there's a steep climb followed by a steep, long and straight descent. I was on a club ride when I used to ride road and the ride leader had a GPS speed (early one so don't know how accurate) of 92kph registered. As he was on the front and a few of us were catching him I probably hit a few kph more! One other guy had a Cateye computer (wheel magnet type) and it only went up to 99 and froze on that for a while.
Off-road I've hit 43 mph (GPS) three times in a row running down the fire road back to the Lindarets lift. Pretty sketchy when you're firing off rocks and despite only jumping a few inches up covering a huge distance before the wheels hit the ground again!
63kph/39mph MTB on road down into Semer Water. Decided not to jump the humpback bridge at the bottom, so slowed down.
56kph/35mph MTB off road, forest track after coming off Urra Moor.
Mine is 76 km/h on a road bike, brakes off, zipping down a hill in Monmouthshire where the cattle grids loom into focus pretty rapidly!
What's cattle grid protocol on a road bike?
84.4kph, descending into Clonmel in Co Waterford on the tandem. With a trailer on the back
Would be cool to have a braked trailer for such situations.
TL;DR Lots of bad GPS data, can't verify max speed. Probably 86.8 km/h with reasonable certainty.
Difficult for me to tell but I was convinced my max speed was ~80 km/h as, BITD (before GPS) I lived on the side of a hill which had a long gradual descent which the transitioned into a short steep section of around 16% and, despite MANY attempts, I never quite cracked 80 km/h on that steep section (as verified by a properly set-up Cateye wired computer).
Up to that point in my life, that was definitely the fastest known speed I was confident I'd done. I'd possibly been a little faster on some of the Lakes, Dales, Welsh or Calderdale rides I'd done but without a speedo or GPS to verify. I also remember hitting a smidge under 80 km/h on my Marin Mount Vision freewheeling down some mountain on Rhodes (the Greek island)
But looking at Veloviewer, I've got tons of rides with a max speed over 80 (topping out at 171!) - now I KNOW I've never seen anything on my Garmin headunit higher than 77 km/h whilst riding (though I guess I wouldn't be looking at the headunit when descending at terminal velocity).
Anyway, that 171 is obviously bollox because (a) it's unrealistic and (b) it was on a commute home from work not down the side of a big hill - and my office is surrounded by tall office buildings so it's obviously bad GPS data.
So, after combining thru some rides which I KNOW had significant descents, and for which I was using a decent Garmin headunit, I'm reasonably confident my verifiable max is 86.8 km/h because it coincided with the steepest section of descent on that ride. That max was very brief though, so I wasn't sat at a high speed for a long time contemplating what road rash would feel like!
75 mph...I'd left the gps turned on when I put the bike on the car roof...
I spent a while chasing 80km/h, lots of 79km/h maximums in Scotland, never saw 80km/h ☹
Felt like I *might* have topped it in the Alps but my wireless Cateye had either just cooked or got too much sweat dripped on it, so I never got to verify it.
Nowadays I find it harder to even get close! Am sure I'm actually slightly more aero than I used to be (lower bars, more awareness, perhaps less aero rims right enough) am DEFINITELY heavier, probably less powerful.
So what's the defining factor, weight and gradient? Or are you spinning a 53x11 to crack 80km/h?
My current ambition is a Strava top ten descending into Dunning, it's a lovely descent, varied gradients, lots of entertaining corners, good surface. Requires a combination of cojones on the corners (of which I don't think I possess the necessary) and power to the pedals on the less steep bits (ditto 🙄)
Edit: top five fastest speeds on Veloviewer are glaring GPS inconsistencies from wilder gravel rides, high 80s and low 90s 😂. First credible max speed of 78.8 is on a steep wee plummet into Bridge of Earn from Glenfarg, on the singlespeed with mudguards and a tiny gear, so unlikely to pedal or aero assisted (and probably still a GPS error 🙄)
There's a hill on South Downs near me where you can touch 60mph/96kmh, which off road isn't too bad. It's straight and on loose dirt/chalk, plus you tend to take off a few times. Certainly gets the adrenaline going and especially if you do it at night.
77kph down Bannerdown in Bath yesterday.
One of the reasons I sacked off road riding was the fact I like to go flat out downhill, and I knew it was only a matter of time until I came unstuck.
54mph off down Newlands Pass, not exactly smooth tarmac 😬
I recall going up Holme Moss too see how fast I could descend. Regularly hitting 50mph and over. I really struggle now on 1 X drivetrains, I need a big tail wind to get high 40s due to the gearing of a 1X.
Or are you spinning a 53×11 to crack 80km/h?
I've 53:11
But I find the secret on glenshee and lecht is to accelerate hard get onto the steep bit stop pedaling and tuck knees into toptube/bring in the elbows.
Pedaling creates more turbulent air round you and you slow down as a result past a certain point.
Even when I've decided to start pedaling to try and break the 100 I've seen my speed slow down as a direct result of starting to pedal.
Went out with the fast-er* roadies last night and got a lesson in how much of a benefit 20years of development has made over shallow alloy rims and chunky round frame tubes. I was struggling to hold 38mph on the descents, all those deep section wheels and fancy frame tubes were coming past soft pedaling despite me having substantially more gravity on my side than some of them!
Is the use of MPH for the cough older generation or of a certain political persuasion?
Either that or they live in the UK were everything** is measured in mph. It's not even like you can argue kmh is an SI unit, it's 0.2777recuring m/s.
*weekend rides 16mph average is considered "steady", and tends to be accurate. Mid week is advertised as "social" (<15mph average) but is also self selecting for people who ride a lot more than just Sundays, so ends up being 17mph+.
**outside of STEM context, although I'm currently working in ft/s because my client is Fred Flintstone.
I can't see an efficient way to find my top speed on free Strava account, albeit I'm normally very cautious on all but wide and straight descents and my road bike is as aero as a brick.
Last year I apparently hit 42.9mph on two rides, including the fun descent I tried for the first time just down the road from Sportsman's Arms to Denbigh.
*weekend rides 16mph average is considered “steady”, and tends to be accurate. Mid week is advertised as “social” (<15mph average) but is also self selecting for people who ride a lot more than just Sundays, so ends up being 17mph+.
Thats your chosen club.
Others exist.
Observation is It tends to be testers clubs that migrate to mph since that's one of the few events that measures in miles
Above 50km/h its more about aero than pedalling. My "road bike" has 40:28 XT crankset on it, so top gear is only 40:11. I still managed to hit 82km/h on the Cairn O Mount south descent and averaged 67.6km/h and that was with a flappy windproof on because it was a cold day.
I topped 51mph on my rigid mtb with 25mm slicks on the road down to Brighton on the London-Brighton charity ride back in 1997
We used to call https://www.strava.com/segments/10130030 the 40mile-an-hour back in the mid 90's when I started riding mtb, because the challenge was to hit 40mph or 64km/h before you hit the brakes at the bottom. This was on fully rigid bikes with 1.8" tyres.
Thats your chosen club.
Others exist.
It was more a comment on how I'd brought a knife to a gun-fight 😂
IME every club I've ever joined has worked in miles though. Trying to be continental and work in km just seems pointless as you then have to do mental maths each time you see a road sign. Why Addaxes use km when you're expected (historically) to navigate from a road book and sign posts is a complete mystery.
Although since they moved to organizing via strava rather than yahoo groups it's irrelevant as if it's advertised by the leader at 30km/h it automatically translates to 18.75 (or vice versa if I organized that ride it would appear to them as 30.5km/h).
59.8mph on a road ride. I wanted to break 60mph, but having nearly done it i can't say i want to try again
I hit 46mph down Old Durham Road in Gateshead.
The speed didn't scare me at all, until I found out the pads were glazed, and there were a couple of sets of lights and a roundabout at the bottom to contend with. With the levers hard against the bars, I struggled to get it under 25mph until the road flattened out.
This was on my CAADX with cable discs. I converted it to flat bar and hydraulics soon after
I don't think I've cleared more than 33mph, but all my proper bikes are 1x and I don't do much road riding. Was pretty chuffed getting up to 23.4mph on the Brompton the other night tbh
Butser Hill South Downs,
54mph , going through the gate was terrifying, arse twitching like a rabbit’s nose.
Never again. 🤓
What’s cattle grid protocol on a road bike?
Hop? Even lifting the wheels 5-8cm will see you in the air for several metres at these sorts of speed.
So what’s the defining factor, weight and gradient? Or are you spinning a 53×11 to crack 80km/h?
Weight, gradient and aero. Power is almost an irrelevance at anything over about 60kph (you need about 700w@50kph and 1200@60kph then 1800@70kph, so pedaling like a loon might only gain you 10kph, if you've even got the legs to spin 53:11 from 60 (cadence of 95) to 70 (about 110) while developing 600W... and it'll add big chunks to your drag.
But going from drops to a full stupid, chin on the top cap tuck, at 60kph might gain you over 300W. For free.
The highest speeds i've ever done have been aero/wind assisted and sustained gradient (not necessarily steep, but long) and being very brave/stupid with the brakes.
I can’t spin past 40kmph on my bikes both mtb (1x11 32t), but still regularly crack 75-80 and made it to 98. Dropper definitely helps.
I can’t spin past 40kmph on my bikes
I can spin past 50 (almost 60) on 32:11, but while a cadence of 150 is doable, it's not hugely enjoyable, easier to tuck and roll...
The theoretical 90kph i can spin to on the road bike hasn't ever been realised.
Pretty fast.
Fewer cars on the road this morning, but damp with a head wind, and road works in the run up to the speed run.
38mph. More to come.