How fast is too fast for you?

[GhettoWedo74]

So this is a question that came up amongst friends recently. How fast on a downhill is too fast? Of course, a lot of variables go into that so go ahead and explain it all to me.

For me, typically my comfort zone is around 20-25 mph on unpaved roads and 30-35 mph on paved roads. But this can vary quite a bit depending on the condition of my tires and brakes, the actual road surface, weather, and traffic.

I've also noticed that on very long downhills, my average speed is quite a bit higher in the very lower fraction than in the upper parts. Also, for clarification, my definition of "very long downhill" is usually on the order of ten miles and 2500+ feet of elevation loss.

In great conditions with new tires and brakes I've hit 35 mph on unpaved roads a handful of times.

For absolute fastest speeds ever for me, on an arrow-straight section of very lonesome highway in Eastern Washington with brand new butter-smooth asphalt, no traffic and no wind I hit 48 mph through a very broad valley.
This was on new tires and new brakes as well. Unfortunately, such optimum karma only occurs once or twice per year.

I just got 43mph on my Fiido T1, a hybrid e-Bike, & averaged around 40mph down the whole mountain, & was surprised at how stable it felt, & what a fun ride it was!
The only thing that happened I rattled my M5 out of my kickstand, but other than that, it felt really sturdy at those speeds.

I have a Hisunyes e-Moto on the way, & it's capable of 55+mph, & they're more than fast enough for me. It's 180lbs, & built like a proper motorcycle, not like these bicycles parading as an "e-Moto" , with bicycle components that these companies are selling to untrained riders that never even rode a motorcycle before, & never at those speeds.

I also wear DOT Approved gear, since we're usually traveling at double the speed of an average bike riders, & our injuries are more akin to motorcycle accidents.

If you ride fast guys, wear good gear, & also make sure you're familiar with those speeds & rode motorcycles before

 

[BlackHand]

Almost mach3 according to RideWithGPS, though TBH it felt more like about 25mph at the time.

Seriously though, around 34-35 mph I start to feel like a kite, my bike is plenty stable but not really the right geometry for high speed descents.

 

[Mr. Coffee]

That kind of hill might, I say might, exist in Tennessee in the Smokey Mountains.

You don't have to look that hard:

Newfound Gap to Sugarlands Visitor Center Loop Road

www.google.com

 

[Tars Tarkas]

You don't have to look that hard:

Newfound Gap to Sugarlands Visitor Center Loop Road

www.google.com

That was the ONE I thought of. There might be others but there aren't many.

TT

 

[mschwett]

I've also noticed that on very long downhills, my average speed is quite a bit higher in the very lower fraction than in the upper parts. Also, for clarification, my definition of "very long downhill" is usually on the order of ten miles and 2500+ feet of elevation loss.
…

that’s a very interesting and VERY long descent. ours tend to be shorter and/or steeper.

That was the ONE I thought of. There might be others but there aren't many.

TT

5% for 13 miles would be a fun ride!! but those kinds of distances are hardly necessary to reach escape velocity!

it only takes a half mile or so at 6% to get far beyond what most cyclists are comfortable with, at least, on a road bike. i suppose the greater drag, bigger tires etc of some types of e-bikes might neccessitate a steeper grade, but more distance isn't really going to help! here's the fastest run (not mine) of a nice short local descent that's straight enough to really let it rip:

and in the mere mortal category, here's my fastest! 44mph is definitely right at my max comfort level.

 

[Mr. Coffee]

that’s a very interesting and VERY long descent. ours tend to be shorter and/or steeper.

I can't swing a cat here without hitting a hill like that:

Banker Pass to 559-549 Co Hwy 1213

www.google.com

Goat Peak Lookout Trail to Goat Creek Sno-Park

www.google.com

 

[mschwett]

I can't swing a cat here without hitting a hill like that:

Banker Pass to 559-549 Co Hwy 1213

www.google.com

Goat Peak Lookout Trail to Goat Creek Sno-Park

www.google.com

yep, coastal CA is similar, hard to go far without 500-2000’ climbs. but not much higher than that, thankfully, i think!

 

[Rickman1]

Majority of the time I ride at around 12 to 14mph. Occasionally I will ride 16 to 20 mph for a brief period. When I have the road all to myself, once in awhile I will see how fast I can get up to. So far the fastest speed I obtained was 32 mph but just for a brief period as that's pretty damn fast on a bicycle. I'm at that juncture in my life when things break or wear out too easily and it takes forever to heal. I'm riding for the enjoyment and to improve my life and health... not end it!

 

[Mr. Coffee]

yep, coastal CA is similar, hard to go far without 500-2000’ climbs. but not much higher than that, thankfully, i think!

Yeah, the fun challenge is finding HUGE drops:

Hurricane Ridge Visitor Center to Port Angeles

www.google.com

Timberline Lodge to Mount Hood Village

www.google.com

Oh, not a continuous drop but damn that is a long way down:

White Mountain Rd · White Mountain Rd, California

White Mountain Rd, California

www.google.com

And if you start from the summit you can get another 2000-odd feet of descent.

 

[mschwett]

Yeah, the fun challenge is finding HUGE drops:

Hurricane Ridge Visitor Center to Port Angeles

www.google.com

Timberline Lodge to Mount Hood Village

www.google.com

Oh, not a continuous drop but damn that is a long way down:

White Mountain Rd · White Mountain Rd, California

White Mountain Rd, California

www.google.com

And if you start from the summit you can get another 2000-odd feet of descent.

if you’re gonna go for it, may as well go big!!!!

 

[tomjasz]

Yikes you fellas are goats! We have some country hilly roads. MN gravel, but Wisconsin paved the famous “ABCs”. But no accents over 500’. 36v 359w mids and little cartage or gear took on the road and performed well. The same route with BBSHD’s was a giggle a time or two.

 

[Kayakguy]

I do know not to ride the brakes down a hill but I definitely use them to get speed under control
So far never had any brake fade but always worry about it and am careful

One thing I learned on motorcycles: scrub off the speed BEFORE you hit the curve. I see accident reports where the motorcyclist "failed to make the turn." Same thing on a bike, but maybe more so, as our braking power is much weaker.

 

[Kayakguy]

Yeah, the fun challenge is finding HUGE drops:

Hurricane Ridge Visitor Center to Port Angeles

www.google.com

Timberline Lodge to Mount Hood Village

www.google.com

Oh, not a continuous drop but damn that is a long way down:

White Mountain Rd · White Mountain Rd, California

White Mountain Rd, California

www.google.com

And if you start from the summit you can get another 2000-odd feet of descent.

It's probably best not to start thinking about a tire failure at those speeds.

 

[ChezCheese:)]

I can't get off the hill I live on without coasting at 37-39mph.

It is interesting that I coast faster than my husband does on his Vado 6. Why would this be? We are not too dissimilar in weight, but his weight is more in his upper body while mine is more in my lower body, so maybe bike+me has a lower center of gravity and maybe that might be the reason? We both have Brose motors, though his is Specialized and mine is BH. Any theories?

 

[fooferdoggie]

I can't get off the hill I live on without coasting at 37-39mph.

It is interesting that I coast faster than my husband does on his Vado 6. Why would this be? We are not too dissimilar in weight, but his weight is more in his upper body while mine is more in my lower body, so maybe bike+me has a lower center of gravity and maybe that might be the reason? We both have Brose motors, though his is Specialized and mine is BH. Any theories?

same size tires and psi? that ca n make a big difference. then air resistance too thats another one.

 

[Stefan Mikes]

Any theories?

You are a smaller person than your husband is and create less air drag!

 

[Tars Tarkas]

Any theories?

How much faster? Maybe he touches his brakes more than you do. Maybe the grease in your bearings is in better shape than his. Maybe you cut the curves tighter than he does.

39 mph is pretty much bat out of hell kind of speed! Be careful!!

TT

 

[kmccune]

36 mph on good pavement with no rocks water or mud. We have deer here that tend to sprint across the road suddenly at the bottom of the hill. Stupid as bunny rabbits (that I've run over). Come right into town sometimes: there was a news shot of a deer on 3rd street in downtown Louisville near Galt House. At least the bears stay in the suburbs. Really, I'd hate to hit a ground hog or raccoon at that speed.

My one little hollow with a standard ebIke will get me up to 35+ mph easily with me in full aero drag configuration( do not want to go faster the deer hang around in the little "Hollow mouth" at the bottom, what surprised Me was how much drag 4 in tires create( in drogue chute position, do not want to hug the bike feel like I have more control sitting upright.
Had a Friend who followed a roadie doing 55mph on a downhill grade, way too fast for this old Zorro.

 

[kmccune]

How fast is too fast? When I'm going fast enough to wonder if my health/life insurance is paid up to date.

More seriously, there's so many factors to consider...... Like the potential for a deer to step out in front of your noiseless bike, a car to pull out from an unseen driveway, etc. etc. Then there's the bike itself. Is it feeling rock solid, or maybe a little dodgy. The surface you're on, conditions, the list goes on and on.

Worth mentioning I think, is that riding your brakes down a scary hill is a bad plan. Same as when you're in a car or truck, that practice will have you smelling your brakes soon. Grabbing a hand full of brake and slowing significantly/quickly then releasing (to let them cool for a few seconds) then repeating as necessary, has way less tendency to overheat the brakes..... -Al

People will argue about that, the argument was "Apple and Oranges" He said if you intermittingly hit the brakes on a "Euc" or heavy truck you would have them in flames shortly( they had oil-cooled brakes, maybe so I always depended on a jake brake or retarder) However I still agree with you under most circumstances. I had a big cruiser that was easy to get the brakes stinking on, by riding them a bit.

 

[kmccune]

You don't have to look that hard:

Newfound Gap to Sugarlands Visitor Center Loop Road

www.google.com

A Friend of mine used to commute across a steep ridge or Mtn if you will, at the top He would air His tires way down and stop at a service station at the bottom and air up again, He decided to go all the way without "airing down" once( He didn't make it) I never asked Him how bad He got hurt. (Around a 1000' in 3 miles fairly steep in places)