Adventure Cycling Association Forum

Bicycle Travel => General Discussion => Topic started by: New Jawn on July 02, 2022, 04:05:51 pm

 
Title: Long, steep descents -- questions about safety
Post by: New Jawn on July 02, 2022, 04:05:51 pm
Not long ago I finished a section from Oxford, OH to Newton, KS -- yes, some hills but nothing that I would call mountainous.  Now I'm looking at some long rides that will definitely have steep descents, some perhaps long, continuous descents (think western CO) or long descents with lot of curves (Appalachian Mts). 

So, just let it roll unchecked?  I would guess that speeds  could easily go over 40 mph and perhaps higher?   Just thinking about it makes me a bit nervous.  Assuming the road isn't too curvy, just not worry about how fast I'm going?   I've seen Tour de France footage of those guys going downhill like rockets and there's no way ever that I would have the guts to do it. 

If I try to keep the speed down, I'd think that my brakes could overheat (Surely Disc Trucker), so alternate front and back brake?

Any advice on how to address long, steep descents in a safe manner?

Thanks in advance.
Title: Re: Long, steep descents -- questions about safety
Post by: jamawani on July 02, 2022, 04:56:39 pm
I think I got up to 53 mph loaded down with gear on a long, straight descent in Nevada.
I actually passed a dump truck that had down-shifted.
The driver saw me coming up behind him and had a shocked expression.

But really - airport runway straight and almost zero traffic - plus I had 1.95 tires.

Descents depend upon a number of things:
1. % Grade - The steeper it is the more likely you may get into trouble.
2. Road Width - 12-foot lanes or less? Shoulders? Mountain roads are often narrow.
3. Traffic Volume - The more traffic there is the more the challenge. Drivers are grumpy if you are just doing 30 mph.
4. Road Surface Condition - Mountain roads often have more wear & tear. A sudden pothole and you are done in.
Also 5. Brakes - Disc brakes or rim? Disc brakes are more powerful and rim brakes can really heat up your rims.

In contrast to Nevada, I've ridden Going to the Sun in Glacier N.P. more than a dozen times.
The west side has a longer descent at a constant 8%, but the road is narrow and packed with cars.
What I do there is stop frequently at overlooks to let traffic go by and then start again in the gaps.

Obviously, if you have a lot of switchbacks, you can't let it rip.
(If you are not sure, you should expect a switchback or two just to be prudent.)
Also, be careful for the oncoming, uphill traffic.
Impatient folks behind a slow truck can and do pull out into your lane to pass.

Hope this helps. - J
Title: Re: Long, steep descents -- questions about safety
Post by: Pat Lamb on July 02, 2022, 05:32:29 pm
In addition to John's road condition consideration, I'd add whether or not there's gravel (or rocks) on the road, and whether the road and/or your brakes are wet.  There was one lovely pass where the road was a consistent 6%, but there were occasional 3-6" rocks on the road -- you want to make sure you can safely steer around those!

Also, brake early and often if it's raining so you can clear your brakes.  Rim or disc, if the braking surface gets wet you don't have brake power.  And yes, it can happen with a good rain rate on discs!

Other than that, brake as you need to maintain your speed so you can steer the bike.  Riding the brakes is bad, you're better off either alternating wheels (front for 10 seconds, rear for 10 seconds), or pulsing the brakes (brake hard for 5 seconds, let it roll for 5).  If you think the brake surface is getting too hot, stop and let it cool.  Take a few pictures, have a drink and a snack, squirt some water on the rims and see if they've stopped hissing when you do that.  It's possible to blow even a mountain bike tire off the rim if you overheat it too badly; skinnier tires at higher pressure are closer to blowoff if you ride the brakes.
Title: Re: Long, steep descents -- questions about safety
Post by: Westinghouse on July 02, 2022, 06:50:49 pm
I have done some very long steep descents. One was so long and steep and at such an angle that by the time I got down to level ground again both hands felt as though they had been beaten with a hammer. All I can tell you is this. Work the brakes alternately and sometimes front and rear at the same time, off and on off and on off and on. I have heard of rims Heating and popping the tube. Never had that problem. Just break to keep the speed down and let off. Break to keep the speed down and let off, and just keep doing that.
Title: Re: Long, steep descents -- questions about safety
Post by: aggie on July 03, 2022, 10:25:47 am
In addition to everything mentioned above - be wary of loose gravel.  I was coming down Mt Graham in AZ, wasn’t loaded with gear, had to be doing at least 30 mph just before a hairpin curve.  As I was breaking I hit a patch of gravel.  Not sure of the exact chain of events but front tire went flat - bike and I did a complete flip.  Broke my collarbone and a couple of ribs and my helmet was cracked in 5 places.  Needless to say I am very cautious before entering any hairpin curves.  I slow down well before the curve.
Title: Re: Long, steep descents -- questions about safety
Post by: staehpj1 on July 03, 2022, 10:41:41 am
I have known of a few tour ending or tour interupting crashes on long fast downhill runs, but I love bombing downhills and tend to let it all hang out.  That said if you want to be sensible, alternating front and rear braking, keeping speed down, stopping for breaks on the way down all help.  Also your disc brakes are better for avoiding melting a pad or blowing an overheated tire.
Title: Re: Long, steep descents -- questions about safety
Post by: ray b on July 03, 2022, 01:00:59 pm
Title: Re: Long, steep descents -- questions about safety
Post by: John Nelson on July 03, 2022, 07:44:20 pm
I live in Colorado. Long, high-speed descents are part of my ride almost every day. It does take some getting used to. The more you do it, the more comfortable you get with it.

Speeds in the low 40s MPH are no big deal. As the speed gets into the upper 40s and low 50s, hyper vigilance is required. How smooth is the road? How straight is it? How clean is it? What’s the likelihood of side traffic? Can you see around the next curve? Is there traffic behind you? Coming up? Don’t let your speed get above 50 unless you get the right answer to all these questions.

Don’t brake excessively. It can cause lots of problems. Overheating your rims (if you have rim brakes), wearing out your brake pads, surprising the cars and bikes behind you, stressing your spokes.

When you get close to a curve, brake hard enough for the entire curve. Be more cautious if you can’t yet see where the curve ends, or if the grade is steep throughout the curve. Don’t brake in the curve itself, or do so very lightly. Lean your bike. As you come out of the curve, release the brakes and don’t reapply them until you get close to the next curve.

I don’t place much stock in the alternating front and back brakes idea. When you need to brake, use both brakes and brake hard. Keep your arms stiff and your butt back. Then let you brakes go completely. Do not lightly apply the brakes continuously for a long time.

Keep your bike in good repair. Check and adjust your brakes frequently. Do not ride on worn-out tires. Keep your tires inflated to the correct pressure. Make sure your wheels are true. If you are predisposed to high-speed wobble, lean your knee against the top tube (and get a different bike as soon as you can).
Title: Re: Long, steep descents -- questions about safety
Post by: ray b on July 03, 2022, 09:53:58 pm
John always manages to pack the critical info into a readable post.

In thinking further about what makes me comfortable at over 60 mph, I'd have to add the motorcycle.

John mentions hypervigilance and where your eyes need to be. Riding a motorcycle at speed certainly helps get the brain reved up for speed.

Sent from my SM-N950U using Tapatalk

Title: Re: Long, steep descents -- questions about safety
Post by: OHRider on July 04, 2022, 09:34:46 am
We had a very long descent in high winds and warm temperatures in last fall's Southern Tier ride- The descent was on an interstate highway with fairly heavy traffic.  Due to the winds both my friend and I were braking heavily to keep the speed down. Trucks would buffet us which required hypervigilance as described earlier in one reply.

My bike had hydraulic discs and 700x32C's and my friend's bike had rim brakes and 700x25C's.  The highway shoulder had a lot of debris, much of which you couldn't see until you were right on top of it.  I'd say we kept at 20-30 mph most of the way and made a couple of stops to let brakes and rims cool off (our host had recommended catching a ride down the hill which likely would have been the wise choice).

Luckily we both made it to the bottom safely. When Brian pulled off at the last ramp and came to a stop his tire blew. Sigh of relief that it was there and not higher on the mountain.

We both had issues with rim tape moving during the trip- which once it opens up a sufficient gap to the spoke hole you will pop the tire.  I think this has been due to heat so beware of steep fast descents if it's hot.

Nothing I love better than flying down a hill but it's best to err on the side of caution- a loaded bike stresses brakes and wheels much more than an unloaded road bike.  At least panniers do a pretty good job acting as air brakes and keeping top speed down.
Title: Re: Long, steep descents -- questions about safety
Post by: BikePacker on July 04, 2022, 10:56:08 am
The original post prompts 2 thoughts:
1. As I was in a bike shop somewhere just east of the North Cascades and heading east, I heard sirens. 
Upon doing so the shop owner said it was for a cyclist who was coming down the same road I was just on and
the cyclist had an animal wander out into his path (he heard the report on his radio scanner tuned to a local EMT frequency).
Shop owned added (paraphrased) 'Happens about once a month - critters can not hear the cyclist coming down the mountain ...
if the cyclist is going too fast to control his rig, the outcome can be not good for the cyclist.
'
2.  Was surprised at how much the wind resistance (think front panniers : ) had on slowing my speed.
Title: Re: Long, steep descents -- questions about safety
Post by: staehpj1 on July 04, 2022, 11:16:47 am
1. As I was in a bike shop somewhere just east of the North Cascades and heading east, I heard sirens. 
Upon doing so the shop owner said it was for a cyclist who was coming down the same road I was just on and
the cyclist had an animal wander out into his path (he heard the report on his radio scanner tuned to a local EMT frequency).
Shop owned added (paraphrased) 'Happens about once a month - critters can not hear the cyclist coming down the mountain ...
if the cyclist is going too fast to control his rig, the outcome can be not good for the cyclist.
'
Yeah, one in my group had a semi close call with a cow moose or an elk (I forget which) on a downhill in Yellowstone. I and others I have been with have had similar with whitelail deer and once with a pronghorn antelope.  Only close calls though.  A few were real close while mountain biking.  When I was racing hare scrambles (motorcycle) a guy preriding the course hit a bear and separated his shoulder.  The bear ran off with no obvious injury.

Probably the one that came the closest to crashing me was when a squirrel ran into my spokes.  Fortunately for both of us he bounced off rather than tangling.

My dad had a poodle take his front wheel out and he suffered a broken collar bone.  It was on flat ground though.

So animals taking out or at least almost taking out bikes is a more common occurance than one might think, I guess.
Title: Re: Long, steep descents -- questions about safety
Post by: HobbesOnTour on July 04, 2022, 11:26:12 am
I'm glad someone mentioned wind!! That can be tricky.
I've nothing to add to the excellent advice offered above (maybe not a good idea to scare the poor OP with stories  :) )

However, I really hope that they'll come back to their threads when they've completed their tour and update them with the benefit of experience.

There's a world of difference between sitting at home and thinking about a big tour and actually getting out there and doing it.
In my experience the things that seem so scary sitting at home turn out to be interesting parts of an adventure, sometimes among the highlights!
I hope the OP finds similar.

Title: Re: Long, steep descents -- questions about safety
Post by: BikePacker on July 04, 2022, 11:57:59 am
... maybe not a good idea to scare the poor OP with stories  ...
For me,
I'd rather read the news reports and learn / benefit from same,
so that I am more able to tour with greater awareness of possibilities.
Title: Re: Long, steep descents -- questions about safety
Post by: staehpj1 on July 05, 2022, 06:45:13 am
(maybe not a good idea to scare the poor OP with stories  :) )
I should add that the stories I mentioned were spread over my experiences and people around me over the last 50+ years.  Also consider that I rode trails that were over run with deer and rode at racing speeds.  Also the actual crashes were really rare, most were just close calls.  The few interupted tours were strangers that I met or heard of when on the trans america or other long tours and one co worker whose incident I learned about years later when he was telling me about his 1976 bikecentennial ride (downhill crash in the rain, broken collar bone, Appalachians, went back and finished the route after healing).

So those events were widely spread and pretty rare events.
Title: Re: Long, steep descents -- questions about safety
Post by: Pat Lamb on July 05, 2022, 08:58:44 am
A few more thoughts.

First, the points about pannier drag and wind are spot on.  My unladen terminal velocity on a 6% downhill is probably over 50 mph, but I hit the brakes when traffic or crosswind buffeting has me wondering if I can control the bike at that speed.  (So my lifetime max is only 49.4 mph.  Sniff.  It was glorious!)

I've rarely exceeded 40 mph with panniers.  Maybe I need an 8-10% grade where I know there's a nice runoff at the bottom?

Second, practice letting the bike run on your training rides.  I remember one bicyclist who was almost petrified going down an 8% grade, and riding her brakes to keep her speed down to 10-12 mph, wobbling back and forth across the lane as she did so.  The 3/4 mile of traffic backed up behind her was not impressed.  You don't want to be her.  So work your way up to a comfortable 30-40 mph or so in good conditions.

Also remember, if you start getting speed wobbles, (1) relax, (2) don't hit the front brake, (3) if you can, put one or both knees against your top tube.
Title: Re: Long, steep descents -- questions about safety
Post by: Westinghouse on July 06, 2022, 01:55:43 pm
Just keep breaking the speed by squeezing both brake levers. Just slow down the speed and then let go. Do it again and let go. Just keep doing that. You will get the feel of it when you are on the road doing it.
Title: Re: Long, steep descents -- questions about safety
Post by: New Jawn on July 11, 2022, 08:50:41 am
Did some traveling and camping last week and did this loop.  It had several big climbs and two really big descents.  The road had no shoulders, often crumbling near edges, every curve was blind, and a good bit of rocks, walnuts, and debris in the road.  Had to go through a long one-lane tunnel with no lights, so I waited until a car was going my direction and asked if I could follow in behind.

Had no packs other than Ortlieb handlebar pack and carried nothing with me but spare tube and tire levers, multi tool, 1/2 liter of tea, snacks, and two cans of Halt II and 6" lock blade knife. 

Top speed on a descent was 27, and that was more than fast enough for me.  I noticed that I have a tendency to ride the brakes, so I guess that I have to learn and practice new ways to slow down.  I do not feel comfortable at all going fast.  I also don't have a good plan for what to do when being passed by car and pushed near crumbly road edge.

I did the ride in both directions, clockwise in morning, counter in afternoon.  The heads-up cautions in the notes were helpful.

 https://ridewithgps.com/ambassador_routes/976-red-river-gorge-classic?lang=en
Title: Re: Long, steep descents -- questions about safety
Post by: HikeBikeCook on July 11, 2022, 05:53:02 pm
You need to ride at your comfort level. Each one of my bikes handles a bit differently and loaded bikes pick up speed faster and may shimmy a bit a certain speeds depending on how you have it loaded. As I have gotten older I tend to sit more upright, which actually helps keep my downhill speed in check by using my body as a braking foil.

As for cars, depending on the posted speed limit, I tend to take the lane on a fast downhill. If I am pushing 30+ most cars will willing follow at a safe distance until it is clear to pass. I find it is better to be in the lane and force them to deal with you than to get forced onto a crappy shoulder - but you have to feel comfortable doing it.

Disc brakes tend not to over heat like rim brakes. I did a high Alpes tour some years back (steep descents and lots of hair-pin corners) and I was usually the last one down the mountain. I managed to burn through my rim brake pads pretty well, but I did not have over heating problems since I did not "ride" the brakes but used them sparingly to keep my speed under 40 mph which helped me slow for the tight turns. It was during the TDF so cars and bikes were mixed tightly sometimes, but drivers were bike aware.
Title: Re: Long, steep descents -- questions about safety
Post by: Westinghouse on July 12, 2022, 04:06:05 am
Another point. Not all brake pads are created equal. I did a Crossing on the Southern Tier of states from Southeast Coastal Florida to San Diego California. I use caliper brakes with brake pads that rubbed on the rims. These were the cheap brake pads from Walmart, about $7.50 for a set of four. I wore down completely one set of four, and through about halfway another set of four. Taken together that would be like completely wearing down to the metal five brake pads or 6. I did another Crossing on the same route from Southeast Coastal Florida to San Diego. That time I used more expensive brake pads. I used only two brake pads and only on the front wheel. The back wheel had no breaks at all. Those brake pads held up all the way across the continent with plenty of braking power to spare by the time I got to San Diego. You get what you pay for.
Title: Re: Long, steep descents -- questions about safety
Post by: mattdwyerva on July 30, 2022, 06:25:56 am
Lots of advice here already, but my two cents:

0) practice on big hills without any panniers first

1) the death wobble that some bikes develop at high speed is terrifying, so if a new bike, be cautious on first few descents carrying a load, and use one or both knees to clamp top tube if it happens, as others have said

2) if braking too hard, your tires may skid and that is hard to control.  If that happens stop braking and steer.

3) if gravel road, be careful while braking as easy to skid in gravel, and skidding might be the start of crashing.  Brake before the turn, then turn with minimal braking.

4) Icefields Parkway scared me 40 years ago as road surface was corrugated suddenly coming around a curve at high speed.   Became hard to steer and hard to brake safely.  Caution is  better but I miss my youth :)