Maximum recommended speed for a road bike?

cmhill79

Hi folks
I was in a discussion with a bunch of cyclists recently and the topic of highest speed ever reached came up. I myself have never been past 70 km/h (and even that felt dangerous) but some of these guys claimed to have broken the 100 km/h (~ 60 m/h) barrier.
This brings me to my question. Is there a recommended maximum speed bike manufacturers or wheel or tyre manufacturers specify for the average road bike? Let's assume bikes ridden by semi serious amateurs.
Thanks in advance

smidsy

There are not semi serious people on here to answer you...we are all mad....mmmmmwwwaaaaaahhhhhaaaaa :-)

Big Geordie

I've hit 100km/h on a long straight descent in the Pennines with a tail wind. The road was well surfaced (or as good as it gets up there) and you could see there was no traffic for miles. At that speed I was getting the feeling I was becoming a passenger and really wouldn't have fancied going any faster on a public road but the bike was perfectly stable and felt like it could have done a lot more. You slow down pretty quickly from those speeds just by sitting up so I suspect any limits would be dictated by aerodynamics rather than equipment.

StillGoing

It makes me cringe to think about it, but having come from a life of motorcycles, I'd never venture out on one without the full protective gear on. Not even 100 meters up the road to test something. Yet here we are happily zipping downhill at 40+ mph dressed in nothing but Lycra or its equivalent with a little plastic helmet for some mythical protection.

crankycrank

cmhill79 wrote:

Hi folks
I was in a discussion with a bunch of cyclists recently and the topic of highest speed ever reached came up. I myself have never been past 70 km/h (and even that felt dangerous) but some of these guys claimed to have broken the 100 km/h (~ 60 m/h) barrier.

Be wary of tall tales. :shock: Not to say some haven't reached that speed but people have a tendency to exaggerate a bit. In any case I've never seen any published recommendations on speed limits but the Pros can occasionally reach 70mph in the mountains from what the race announcers say. I guess it would be safe to say that most decent quality, well maintained bikes with quality new tyres would be safe up to at least 70mph, the rider being the limiting factor but beyond that ??. Even 60mph is very difficult to get to though and the fastest I've ever done in 50yrs of riding was twice at 55mph on 2 different long hills with favourable winds and no tight turns to worry about. This guy kindly did some testing showing that his bike was not safe at anything over 106mph.
http://www.youtube.com/watch?v=rTfu0hjVtzE

Bobbinogs

crankycrank wrote:

...
http://www.youtube.com/watch?v=rTfu0hjVtzE

Wow, great clip. I won't spoil the ending for those who haven't seen it...but I never expected that

marcusjb

Pros will reach up to around 110kph on occasion - they have the advantage of the road ahead being closed, good surfaces and the opportunity to recce the roads in advance - doesn't make it safe though!

Those stretches where they let rip, it is, hopefully, less likely that anything will go wrong - straight(ish) with decent surface etc. There isn't much that is going to go wrong. It only goes wrong, in general, when they have to go around a turn - knowing the road in advance is clearly a big help here.

But, you or I, don't have these advantages of closed roads etc. and unless it is a road we use regularly, then speeds like that are not so wise.

What is a safe maximum speed? It is for you to decide - everyone is different in their evaluation and acceptance of risk.

But, in general, don't use the pros as a good guide - they're wired differently to most of us and have some advantages not open to the rest of us (the closed road etc.).

markhewitt1978

Quite, the pros can be reasonably sure there isn't a massive pothole hidden down a dip, or a big patch of gravel just as they sweep around a corner. Or for that matter a car doing a close pass on you just as you're descending at 40mph.

navrig

philthy3 wrote:

It makes me cringe to think about it, but having come from a life of motorcycles, I'd never venture out on one without the full protective gear on. Not even 100 meters up the road to test something. Yet here we are happily zipping downhill at 40+ mph dressed in nothing but Lycra or its equivalent with a little plastic helmet for some mythical protection.

This^

A couple of times I rode on my motorbike to the nearest garage to fill up with fuel whilst wearing denims. Round trip of about a mile. I felt completely naked and very vulnerable and yet I throughly enjoyed touching 50mph in lycra coming down from Val D'Isere towards Bourg. Crazy.

GiantMike

The maximum recommended speed is the speed you're happy to fall off at.

bluefinch

Bobbinogs wrote:

crankycrank wrote:

...
http://www.youtube.com/watch?v=rTfu0hjVtzE

Wow, great clip. I won't spoil the ending for those who haven't seen it...but I never expected that

It's a good job he was wearing his special protective wellies

marcusjb

GiantMike wrote:

The maximum recommended speed is the speed you're happy to fall off at.

I really don't want to fall off at much more than walking pace personally - but you are right for a recommendation. Of course, we mainly choose to ignore recommendations.

As I said earlier, everyone has a different perspective on risk and where their personal acceptance level is. You just need to find the line for yourself. I know where mine is.

Bobbinogs

bluefinch wrote:

Bobbinogs wrote:

crankycrank wrote:

...
http://www.youtube.com/watch?v=rTfu0hjVtzE

Wow, great clip. I won't spoil the ending for those who haven't seen it...but I never expected that

It's a good job he was wearing his special protective wellies

I wonder if wearing my daughter's power ranger outfit will help my top speed? I will give it a go at the w/e club ride (can't possibly go wrong):

hangeron

markhewitt1978 wrote:

Quite, the pros can be reasonably sure there isn't a massive pothole hidden down a dip, or a big patch of gravel just as they sweep around a corner. Or for that matter a car doing a close pass on you just as you're descending at 40mph.

yeah mostly....but that Jens Voight crash a while back on the TdF descent...makes me wince big time

Pituophis

I think it all depends on the conditions really.
Early in the year on a cold, end of winter day I got to 42 mph going down Snake Pass (There was little traffic, and the two guys I was with were going quite a bit faster) and I don't mind saying that I was actually very nervous in the corners and was constantly braking all the way down. :oops: The road was damp but not wet, and I didn't enjoy it one bit.
Mid summer I was in (well mannered) traffic going down a similar type hill dropping into Burnley at 47 mph, not much faster I admit, but I felt completely comfortable and wouldn't have been fazed to be going faster still.
I very rarely get over 40 though to be honest, and would be very surprised if I ever get to 47 again!

I wouldn't like to fall off at any speed though, and I think a faster off would totally kill my confidence, if not me
I try not to think about it.

smidsy

Today on my pan flat route it was 25mph. Wow it was certainly cold and very much fast enough considering the freeze/road conditions.

junglist_matty

My fastest speed this year was 49.3mph, Cadence was around about 130 in the 53/11 gear, it wasn't the steepest of hills, but there was a silly tailwind..... I've never broken the 50mph barrier, I've tried a few times but failed, and I usually descend faster than most; weighing just shy of 100kg helps.

http://www.strava.com/segments/3236898


In reality, I seriously doubt most cyclists have ever gone faster than 50mph, you run out of gears (unless running a stupid front chainring) to be able to pedal safely at that sort of speed, and you'd need a hell of a long straight descent to freewheel faster than 50mph, unless on a closed road, I doubt most would have the balls to corner a blind open road at more than 40mph (and even 40mph is silly fast for a blind corner on open road).

earth

Above 40 mph the wind makes my eyes stream and I can't see. If I wear sunglasses to shield my eyes from the wind then I also have to wear contact lenses. If the wind shields don't do a good enough job then the wind blows the contact lenses out. So 40 is about my safety limit so far.

cookeeemonster

crankycrank wrote:

cmhill79 wrote:

Hi folks
I was in a discussion with a bunch of cyclists recently and the topic of highest speed ever reached came up. I myself have never been past 70 km/h (and even that felt dangerous) but some of these guys claimed to have broken the 100 km/h (~ 60 m/h) barrier.

Be wary of tall tales. :shock: Not to say some haven't reached that speed but people have a tendency to exaggerate a bit. In any case I've never seen any published recommendations on speed limits but the Pros can occasionally reach 70mph in the mountains from what the race announcers say. I guess it would be safe to say that most decent quality, well maintained bikes with quality new tyres would be safe up to at least 70mph, the rider being the limiting factor but beyond that ??. Even 60mph is very difficult to get to though and the fastest I've ever done in 50yrs of riding was twice at 55mph on 2 different long hills with favourable winds and no tight turns to worry about. This guy kindly did some testing showing that his bike was not safe at anything over 106mph.
http://www.youtube.com/watch?v=rTfu0hjVtzE

my god...that's...awful...

Was he really riding a hybrid?!?!?!?

adr82

50mph is the fastest I've gone on a few occasions. It's hard to find hills in the UK that are long+steep+smooth+safe enough to get tucked down and really let yourself go.

ugo.santalucia

If you want to go fast (60 mph and above) you need

1) Tubular tyre that don't blow up and kill you, possibly inflated at medium pressure

2) Balanced wheels that can spin at that rpm

3) A perfect frame and a solid set of forks

People have reached speed in excess of 100 mph on a bike, just look on wikipedia

crankycrank

CookeeeMonster wrote:

Was he really riding a hybrid?!?!?!?

There was an entire TV show done on this guys crash and they talked to the "engineer" who designed a special bike for the record. The designer was really surprised that the headtube broke off. I guess he's never seen an off-road motorbike frame before.

Initialised

You don't need a mountain.



Half mile stretch, 175ft dropped, maybe 15mph tailwind that day but there was a car in front of me, not sure if it was holding me up or providing a draft once I caught up with it, probably both but it would have been rude and dangerous to overtake as the road flattened out and the corner loomed. I was riding my Specialized Secteur Disc on 28mm tyres in baggy shorts, close to spinning out on 50x11. The bike handles like a hardtail and with relatively fat tyres and decent brakes it didn't feel dangerous compared to descending a ski run littered with boulders the size of your head at 30 mph on a hardtail. It was my third or fourth time down the hill that day, the climb snapped my chain the day before so it owed me.

I'll be back in a similar thread next year having broken sixty mph (or some bones and maybe a bike) down that hill.

Emphursis

I've hit 40mph on two or three occasions, oncee on a short, steep hill tucked in behind someone and the second on a longer steep hill, that's fairly straight (although I wouldn't do more than about 45mph in my car down it because the corner at the bottom can catch you out).

Whenever I get above around 38mph or so, my eyes start watering from the wind, made worse by the fact I wear glasses, which aren't exactly designed to be wind shields. At that sort of speed, I think it's aerodynamics that affect you more than anything, because even sitting up slightly kills your speed.

rickeverett

crankycrank wrote:

cmhill79 wrote:

http://www.youtube.com/watch?v=rTfu0hjVtzE

good old carbon fibre

rickeverett

Emphursis wrote:

I've hit 40mph on two or three occasions, oncee on a short, steep hill tucked in behind someone and the second on a longer steep hill, that's fairly straight (although I wouldn't do more than about 45mph in my car down it because the corner at the bottom can catch you out).

Whenever I get above around 38mph or so, my eyes start watering from the wind, made worse by the fact I wear glasses, which aren't exactly designed to be wind shields. At that sort of speed, I think it's aerodynamics that affect you more than anything, because even sitting up slightly kills your speed.

:shock: I would get some new glasses.

I use Bolle safety glasses now.. cheaper, stronger and have better field of vision compared to a lot of rip-off cycle ones. Dont let much air in either.

markhewitt1978

Initialised wrote:

You don't need a mountain.

Haven't done that hill recently, will have to give it a try. . Although 50mph on that bit with poor visibility etc is bad enough in a car - mind you might be easier on a bike as you have more room to move.

Edit: Actually I have been down there - I forgot, was on my old hyrid, managed 31mph - was the second to last ride I did on it before it got written off by a car.

chris_bass

my speed sensor said my max speed was 107 mph on my way to work yesterday, i'm going to choose to believe it! the misaligned magnet was mearley a coincidence!

diy

Over 50 mph on the mtb on grass, don't fancy that on a road bike, with poo for brakes. Maxed out a fire blade once, really wasn't that amazing to be honest. Downside of motorbiking is you don't really get that bothered about fast speeds on a cycle.

I think I'd rather come off at 70 on a motorbike than 40 on a bike though.

nigelgos

http://www.strava.com/activities/64775326 - 54.6mph coming down Buttertubs. I think thats the fastest I've gone. I couldn't brake well at those speeds and if I'd have needed to quickly get back down to say 30mph I couldn't have done so.

Whilst I waited for my more sensible friend to finish the descend a passing walker delighted in telling me that a cyclist had been carted off in an ambulance that morning as his brakes had failed going down the hill. It was a T-junction with a stone wall at the bottom

I must admit there is something about being slightly out of control that I do enjoy - though I try to feed this habit in moderation.

Pompey Monkey

Haha I thought I was a wimp- max recorded speed of 53.5 mph, just before a car overtook me and promptly braked sharply into a 30 mph zone - that's another story though.

I think that I got to well over 60 mph coming down Mt. Ventoux in 1987. My wheels were making sounds that I had not heard at 50 well before I was going a LOT faster!

Also, maxed out an old style computer at 39.4 mph on the flat while sprinting for the Funtington sign once. But I was quick in those days, so it probably doesn't count...