Fast descents

carl_p

Not wanting to hijack Trickyja's thread about crashes, I'm just wondering whether you guys and gals take the opportunity to cane it on every downhill? I must admit I do, primarily because it is great fun, but it occurs to me it is quite dangerous and only needs a slight skid or rut to cause a nasty accident.

I clocked a massive 34.7 mph, woohoo, on friday before eventually running out of descent which is the fastest I've ever travelled on a cycle. However, at the time I did think blimey I'm on on the edge here and there is no margin for error especially with a car up my a4se.

Should I be taking a more cautious safety first approach and looking to conserve energy by freewheeling downhill?

redddraggon

If you know the descent well, and you can see into the distance, and the weather conditions aren't too bad, why not cane it?

Scrumple

I pinged over 37mph twice now on the way to work, downhill. I don't ride back the same way, for obvious reasons.

Not Another Hill

On every club run or training run I (and the others) hit 40 - 45 mph on the descents because we have long enough hills to get up the speed. Very exciting. Feels fast and dangerous. It's best not to think of tyres blowing, ruts, potholes, animals running out in front, bends sharpening to tightly etc. Otherwise I'd be bimbling down at 25 mph max.

Jez mon

If you know what the conditions are like, cane it. Going at 40 mph on a bike is a good feeling!

Lagavulin

Only short, steep hills around here. Haven't hit 40mph yet but having read some of the posts on here regarding speed wobbles and the like I'm not sure I want to. I do want to have a crack at Hartside sometime soon; up and down.

ris

i've manged over 40 a couple of times on short decents around here, riding the airnimal with a failry upright position.

when i can get the kit together to mount the cateye on the spesh i will see i how fast i can get using drops. better check the wheelsize is right or i might be diappointed!

milton50

I remember when I first went down a really steep descent and I though 'right lets see how fast I can go.'

I was crouched so low trying to get an aero position that I could hardly see forward which made it terrifying considering there are potholes and dips in the road. I got up to 41-42 mph but I didn't fancy doing it again. So now I just feather the breaks and go about 30 mph.

If I came to a descent which I knew was smooth and straight then I'd give it the beans.

trickeyja

I live in Cheltenham and I'm fortunate enough to have several good hills round here, which give thrilling descents. I know them well since I have cycled up and down them many times. I always bomb down these descents, but I would be more cautious if the road was either very steep or very bendy, or if wet.

The best round here is Hartley / Leckhampton Hill, which is a fairly straight and steep descent, and I take the whole lane because the limit is 50 and last time I went down at 46.2mph. I feel safe because I'm not going to be overtaken by cars and also from knowing the route. Descent from 900 to 200ft.

Elevation profile: http://flickr.com/photos/95346693@N00/2813685838/

Another rollercoaster is Birdlip Hill, which is steeper and a tougher climb, but going downhill there is one tight bend so you have to slow up quite a bit at this. Normally 40+mph. However it has recently been resurfaced and it has made the road rougher, unfortunately. Descent is from nearly 1000ft to about 300ft.

The A435 down to Charlton Kings is also pretty fast (44.4mph last time I tried), and a 10% descent.

Then there is Cleeve Hill which is another fairly straight and gradual descent; for some reason not quite so fast as Leckhampton Hill; probably because of the road surface. This is from about 800ft to 200ft.

fluff.

In my 20s I caned it down every hill I found, In my 30s I end up thinking `hang on, If I lose it here they're going to be scraping me off the tarmac with a shovel', when the speed gets up over 40 say, and I find myself skimming the brakes a bit. That said it is still great fun afterwards, there's the drop down through Flash in the Peak District I ride down fairly regularly, and the rush when you pass the speed trap at the bottom doing 50+ is intense.

a_n_t

47.4 mph down holme moss today!

http://trail.motionbased.com/trail/activity/6645880

Wasn't even trying to be honest.

dennisn

Carl_P wrote:

Should I be taking a more cautious safety first approach and looking to conserve energy by freewheeling downhill?

Can't remember the guys name but there was one fairly outrageous downhill crash in
this years Tour de France. Over the edge, he somehow stopped but the bike kept going for a mile or two on down the mountain. Sooner or later this will happen to you if you
keep "putting the hammer down" on decents. It's up to you. If you like the thrill of it, I
guess you're going to go for it. I'm 60 and still "like it" although these days I do tend to
temper my speed just a little. Hitting the roadway at 45-50 MPH is definately not all that
much fun.

Dennis Noward

Jazza1969

The first time I hit 40mph on a bike I was terrified. There was so much vibration that I could hardly see where I was going .

Technique has a lot to do with it. Good posture, especially keeping the backside off the saddle to avoid bumps getting transmitted up the spine, is the difference between feeling confident on a descent and feeling out of control.

Braking all the way down is not a good idea either. Either you will ,like I did, wear your brake pads out in just a few months, or worse the heat of the friction could blow a tyre if it's serious descent. Brake where you need to, ie before a bend or change in road layout, and then release.

Keeping the hands off the brakes is the most difficult thing of all, and I'm no daredevil. If you feel in control however on the way down, the psychological need to grab the levers does go away.

Don't bomb down hills you don't know - you need to know what is beyond the visible road ahead, the state of the surface, the presence of debris, crosswinds, bends, humpback bridges, cattle grids etc.

Top speeds are all subjective. I have hit over 40mph on some West Lothian roads I know well. That might be mad to some, but some folk descending the Crow Road in Lennoxtown or the Bealach na Ba in the highlands hit nearer 60, overtaking cars as they go. Now I think that's mental .

johnnyc71

I like to sprint down hills - if safe. Not many long straight descents in my neighbourhood though. I particularly liked it today setting off a 30 mph warning sign, whilst going towards a crossroads. It's quite a rush being on the drops accelerating towards potential doom!!!

fizz

If you know the road, you know the surface and the conditions are good, then yes I see no reason not. At speed you need to read the road ahead and give yourself time to slow or react to potential hazards and obstacles.

Its practice and confidence. I quite frequently hit 40mph ish downhill. I'm quite confident and I'm happy to let the bike run. Remember look where you want the bike to go and it will. If you look at the outside of the corner or that tree you are more likely to crash into because of target fixation.

Jez mon

dennisn wrote:

Carl_P wrote:

Should I be taking a more cautious safety first approach and looking to conserve energy by freewheeling downhill?

Can't remember the guys name but there was one fairly outrageous downhill crash in
this years Tour de France. Over the edge, he somehow stopped but the bike kept going for a mile or two on down the mountain. Sooner or later this will happen to you if you
keep "putting the hammer down" on descents. It's up to you. If you like the thrill of it, I
guess you're going to go for it. I'm 60 and still "like it" although these days I do tend to
temper my speed just a little. Hitting the roadway at 45-50 MPH is definitely not all that
much fun.

Dennis Noward

The rider was John-Lee Augustyn, and no, this will not just happen to you. So long as you know the road and take care you can go fast (40+) What happened to him was he went down a descent he didn't know, and went round a sharp bend too fast. If you know the road and take care around the corners (i.e. don't try and find the limits of tyre adhesion!) Bikes don't just suddenly fall over, I feel far safer going down a hill at 40 than going into a big roundabout.

merlin321

johnnyc71 wrote:

I particularly liked it today setting off a 30 mph warning sign

New experience for me doing that. I`ve only had my roadie for a month and the first couple of times it happened, I kept looking behind to see where the cars were. When I realised there weren`t any behind me I felt like I`d won a huge sprint finish, then smiled all the way home.

When I told the wife of my achievement she thought it was childish and dangerous.
Quickest so far is 38.6mph but still room for improvement.

dennisn

Jez mon wrote:

dennisn wrote:

Carl_P wrote:

Should I be taking a more cautious safety first approach and looking to conserve energy by freewheeling downhill?

Can't remember the guys name but there was one fairly outrageous downhill crash in
this years Tour de France. Over the edge, he somehow stopped but the bike kept going for a mile or two on down the mountain. Sooner or later this will happen to you if you
keep "putting the hammer down" on descents. It's up to you. If you like the thrill of it, I
guess you're going to go for it. I'm 60 and still "like it" although these days I do tend to
temper my speed just a little. Hitting the roadway at 45-50 MPH is definitely not all that
much fun.

Dennis Noward

The rider was John-Lee Augustyn, and no, this will not just happen to you. So long as you know the road and take care you can go fast (40+) What happened to him was he went down a descent he didn't know, and went round a sharp bend too fast. If you know the road and take care around the corners (i.e. don't try and find the limits of tyre adhesion!) Bikes don't just suddenly fall over, I feel far safer going down a hill at 40 than going into a big roundabout.

I think I was trying to say that sooner or later everyone crashes out somewhere, whether
you know the road or not. And yes, big roundabouts(rare here in the US), are scary on a bike(hell sometimes in a car, too).

Dennis Noward

blorg

It's a hell of a lot safer/easier if you know the road. We have some good hills in Wicklow here and I would tend to go north of 70km/h (44mph) on most rides. Fastest ever was 89km/h (just over 55mph) on a sportive descent with a good 20% section. Have managed near 80km/h (50mph) on my touring bike with panniers- near 10km of 7% descent on an utterly smooth road coming down off the mountains into Galicia. There certainly does come a point where you are better off working on your tuck rather than pedalling. I am too much of a wuss to do the hands-on-the-flats tuck though, fingers on both brakes at all times!

To put this all in some sort of context a few years ago I had never gone faster than 60km/h (37mph) and thought that insanely fast. Get up to 50km/h (31mph) on the flat now!

howiejmidlands

My rule of thumb is...............

If i can see the bottom, cane it.

If i know the road, and the conditions are good...cane it.

If i dont know the road, i hold back. The few extra seconds i could gain are better left on the road than in a hospital bed.

And this means, one of my training loops lets me drop down a steep short hill at 40 mph setting off a slow down sign for 30 mph....................yee haaaaa!!

jjojjas

42mph is my fastest on record. That was on the W2W ride on the tourer
I hit 34/36 most days on the way back from work........possibly faster if on the road bike but that has no computer on it.

rob13

I have seen 50mph on a road bike a few years back, although would think it was low 40s. This was on a long straight descent. Its a great feeling, although I had a motorbike crash earlier this year, probably between 40&50mph and suffered a broken femur & wrist from it. At the time I was wearing a full face helmet, 2 piece leathers, kevlar gloves and armoured boots. I dread to think what might have happened had I been in shorts & t-shirt. As a result, i have been on crutches for 3 months, and i have only 50% movement in my wrist. Itll certainly make me think twice about bombing down descents with little protection

oldwelshman

It is not about 2caning it" on decents.
I decend as fast as possible every time, but every time is different. It is totally dependant on weather conditions, road conditions etc.
Recently I hit 63mph 3 times in the MArmotte, but on a hilly sportive in Pembroke rarely got above 30mph due to winding decents with lots of blind bends so it is often the conditions that are the limiting factor with respect to speed gained.
In one decent recently in Italy ,half way down I had very little brakes left at all, the pads were almost worn away, I had to stop and the rims were scorching!!
The top of the climb had about 20 switchbacks, very steep and close together and I had carbon rims and cork pads, didn't last long!!
This combination will also limit your speed on wet decents thats for sure

boybiker

I was definetly skimming the brakes on one twisty hill yesterday in the rain, I normally go down at about 40-ish and yesterday was going at 25 max. When I got home I found that half my rear brake block had gone and turned to paste in the wet

Simon Notley

It's my ambition to reach 60mph one day (preferable 62 so I've also done 100kph) but I only do it on good roads with good visibility and little traffic. I was up to about 56mph in the Alps earlier this year, before dabbing the brakes to pass a camper van... if that van hadn't been there I think I might have reached 70... If I'd had the bottle!

madturkey

I'll freely admit that I'm a wuss on a bike. Most I have ever hit is about 35mph, but that's only on the Downs and I've not been to Europe.

Jazza1969

It's a matter of gravity of course, but a laden tourer or old heavy racer (or rider ) might well go faster downhill than that ultra light carbon machine we all aspire to. It certainly will have more momentum, and will take more braking force to slow down.

Mind you, after the extra effort of getting a heavy bike up a decent hill, you deserve the payback of being able to bomb down the other side.! Provided the brakes are up to the job, that is.

One way of slowing down a descent without brakes on full time is simply to stay upright, with hands on the hoods (provided the brake levers can be fully applied in that position). This could take as much as 10mph off the speed, especially if there is anything of a headwind.

Nuggs

Jazza1969 wrote:

It's a matter of gravity of course, but a laden tourer or old heavy racer (or rider ) might well go faster downhill than that ultra light carbon machine...

I think Newton might have something to say about that...

Monty Dog

Hitting 80kph is quite easy - all you need is a hill about 10% for about a km or so and plenty of welly in top gear. Higher speeds are a lot more critical of technique, getting to high speed quicky and getting your tuck and balance right. Having absolute confidence in the handling abilities of your bike also helps too - watch videos of the likes of Samuel Sanchez and Laurent Jalabert to see how it's done. Proably the two best climbs in my experience for scary fast are the Galibier and the Tourmalet - 100kph+ for those heavy enough and the cajones to match!

Hornetto

I hit 41mph for a couple of seconds on a descent on the Test Valley Tour yesterday - that's my fastest ever. However, just a slight (and I mean slight) bend in the road seemed that much harder to negotiate at that speed and I felt myself drifting towards the verge so I slowed myself down to the low 30s. It was fun getting up to that speed, especially as I hadn't tried (no pedalling involved) apart from being on the drops.

ded

It's a matter of gravity of course, but a laden tourer or old heavy racer (or rider Laughing ) might well go faster downhill than that ultra light carbon machine...

I think Newton might have something to say about that...

Only if you're really unlucky and have achieved free-fall! I'm sure there are some alpine descents where that is possible...

Otherwise you're into a whole load of complex physics about wind resistance etc. But if you assume that two riders have the same air (and rolling) resistance (big assumption) then the fatter one will accelerate faster, since their downhill force is greater than the skinny one...