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Discussion Starter · #1 ·
This is an elaboration of a couple things in "The Kennnedy Today" thread related to speed. I don't use a computer, GPS, or HR monitor any longer - for me it's a bike ride and not a video game. I also believe these devices can be "optomistic" at times. However there are times I'm curious about my top speed on various rides or roads, so I had a look at that using Sheldon Brown's Gear Inch Calculator.
For me, using the calcultor, the highest speed I routinely probably reach is right @ 43-45mph when I drop down Bonny Doon Rd on my road bike. 120rpm [actually I'm not sure I can even pedal that fast], 700 x 25mm tires, 50 x 11t gearing, in a full tuck for over a mile on a 10% grade yields a 42.8mph top speed. And that seems about right, because every once in a while I get passed by a car while I'm doing this:eek: And that seems plenty fast enough, thank you. I wind up thinking It's gonna suck to be me, and it'll take a hunting dog and a map to find my remains if something goes wrong.
And in response to Rensho's query, I find myself most concerned about crashing on road rides because the results are more catastrophic, and the environment is more uncontrolled [more people, more cars, etc], and this little physics gem Mass TIMES [not plus] Velocity equals Force. Meaning, the force at which one's mass hits the ground is multiplied by the increase in speed, not added to it. Give me trails any day.
With all the above as a premise, my question is where are you most concerned about your velocity? Road or Mountain? Which road or trail? And why. Remember it's all relative too, 40mph on some roads is far less frightening than 5mph on some trail descents.
 

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I'm very aware of both. I also ride motorcycles, and when either the MTB or roadbike velocity starts ramping up I notice that If i had a motor I'd be wearing 10x the gear.

My worst injuries have been on pavement, but I still see offroad as having more potential for a serious situation. Hit a tree or rock in the middle of nowhere vs. shave off some skin on a traveled route.
 

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Having fallen on Dogmeat back in the early ninety's and fallen at probably an equivalent speed on Alpine Road on my road bike, If I had to choose I'd take dogmeat every time.

It's harder to hit high speeds in the Bay Area on the road bike, but up in the Sierras were you have long descents without the type of turns that require braking, it's very easy to go way faster then your capability to pedal, tuck and go.

Sorry to post this again, but I doubt he would have survived had he been on pavement, also note he is not pedaling.
 

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6 years ago, I took out my bike computer on the mountain bike. I've been riding clean ever since. I feel like my experience is maximized when I'm not bothered with avg/max speed, cadence, heart rate. On big rides, I'm curious about total distance and total elevation so I bug my friends for that.

Road bike however is another story. Bike computer is almost essential. Otherwise, I go crazy staring at asphalt. My road bike has an SRM and Ibike telling me Joules, Slope, Calories, Drag, Wind speed, threshold. Basically, it's telling me to work harder so I can get back on the mtb.

fc
 

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JMS, there is got to be more speed in you than that.
West side of hw9 is good for 50mph (the 1 mile straight section heading to Saratoga Springs(slow down when you see the 20mph sign, the 15 sign is a bit late)). The East HW9 side is good for 55.
At 55, you'll appreciate a 53x11.

I wonder about this FC, riding no computer thing all the time... I just can't quite make the switch.
 

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Discussion Starter · #8 ·
I wrote "regularly"

rensho said:
JMS, there is got to be more speed in you than that.
West side of hw9 is good for 50mph (the 1 mile straight section heading to Saratoga Springs(slow down when you see the 20mph sign, the 15 sign is a bit late)). The East HW9 side is good for 55.
At 55, you'll appreciate a 53x11.

I wonder about this FC, riding no computer thing all the time... I just can't quite make the switch.
Look carefully, I wrote wrote "regularly" Rensho. I agree with Tahoe BC @ top speed, it's much easier to reach a potentially greater velocity on some of the Sierra passes than @ the Bay Area. Again, I don't use a computer any longer, so this only my perception:
The fastest speed I've reached on a bike was descending the east face of Monitor Pass during the Death Ride. That was in a full tuck, with 40mm deep carbon wheels and bladed spokes. And that was, like Jaguar used to write in there specifications regarding horsepower, "Sufficient".:)
 

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jms said:
The fastest speed I've reached on a bike was descending the east face of Monitor Pass during the Death Ride. That was in a full tuck, with 40mm deep carbon wheels and bladed spokes. And that was, like Jaguar used to write in there specifications regarding horsepower, "Sufficient".:)
:D :D :D East Side of Monitor is one of my Favorites
 

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Not sure what I'm suppose to take from "regularly", or even "routinely", but i'll just leave it be.

If you're riding 40mm deep section carbons off Monitor, you obviously didn't just fall off the turnip wagon. Either that, are you're just a poseur, and since I have ridden with you, I know it is not that.

"And in response to Rensho's query, I find myself most concerned about crashing on road rides because the results are more catastrophic, and the environment is more uncontrolled [more people, more cars, etc], and this little physics gem Mass TIMES [not plus] Velocity equals Force. Meaning, the force at which one's mass hits the ground is multiplied by the increase in speed, not added to it. Give me trails any day."
I'm very sure you mean F=MA, where A=acceleration. In your statement, F, without time is meaningless. Hence if one crashes, and it takes one 2 hours to come to a stop, one hasn't experienced much Force. If one stops in less than 1/2 second due to hitting a tree, one just experienced great Force.
 

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jms said:
where are you most concerned about your velocity? Road or Mountain? Which road or trail? And why.
There are many situations where I'm concerned about my velocity on a bike. To pick one, I'd have to say nights where I'm riding home from work on the road, in the dark, in heavy fog up on a ridge like Skyline in Oakland. I'll slow way down on the descents.

Second situation, off-road night ride with dead battery. (When I was a kid, we used to have a Thursday night ride that left from the Depot in Mill Valley. This was before decent lights, the trick set up was a mini-mag flashlight and an aluminum mini-mag mount. One thursday night I did the group ride, had a blast, said goodnight to my friends and began the descent solo down Eldridge towards home when my light died. I will never forget descending ever so gently, by ear in the shady, pitch-black sections.)

Other situations: On the road when it's cold and wet and there's tar patches or black ice or manhole covers.

On the dirt: technical obstacles with bad consequences, or poor visibility with the possibility of hikers on the trail. I'm not a very good technical rider. If I come to something I can't ride fast or safely, I'll run it.

On road descents, if there are cars around I'll either make sure I'm in front of them or stay back and slow down, or wait for a gap. Ditto for riders I don't know & trust. I ride really defensively around cars.

If I can see, and it's clear, I'll open it up. That is, no faster than 15mph off-road on multi-use public trails of course. :) As TahoeBC said, there are some roads in the Sierras where it's unnerving to descend in long straight lines really fast for long amounts of time. He's a good descender, he knows what he's talking about. Road descents in the Bay Area where I feel I can rip it up: Pantoll to Stinson, Marshall Wall either east- or west-bound, Pt Reyes - Petaluma west-bound towards Nicasio, Diablo either way, all the Bears in Orinda. (I don't ride on the Peninsula very often, I'm sure there's more there!) Oh man, just thinking about these descents makes me want to go ride!

I've gone 55mph+ on my road bike plenty. I've been over 50mph off-road on the back of a tandem. Have seen 63mph max speed on my road bike's computer twice. I've crashed plenty, but never faster than thinks... 40mph. I've seen two people crash at 50mph+ in road races - not pretty. Each time they lost control, I watched it happen. (One touched a wheel in front of him at 50mph+ and freaked out, the other was too close to the edge on a winding Sierra road, descending, hit decomposed granite on the side of the road and we never saw him again. Both were in pack racing conditions.) My worst crash resulted from being hit by a car on the road, second worst was riding in the dark with insufficient light and losing my front wheel in an unmarked, fresh hole in the bike path, third was some doorknob deciding to move over across my front wheel in a practice criterium. (road) Managed to separate my shoulder this fall in one of the DFL practice cyclocross races, road down a tricky drop with poor technique right after a remount and went over the bars. (While wearing a miniskirt no less!) Most road crashes have meant road rash for me at worst, a pain in the ass (heh) but not a huge problem. Been going fast down hills for 25 years.

Morgan
 

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francois said:
6 years ago, I took out my bike computer on the mountain bike. I've been riding clean ever since. I feel like my experience is maximized when I'm not bothered with avg/max speed, cadence, heart rate. On big rides, I'm curious about total distance and total elevation so I bug my friends for that.

Road bike however is another story. Bike computer is almost essential. Otherwise, I go crazy staring at asphalt. My road bike has an SRM and Ibike telling me Joules, Slope, Calories, Drag, Wind speed, threshold. Basically, it's telling me to work harder so I can get back on the mtb.

fc
I'm a data junkie. I have a training plan. I use software called WKO+ to track all my training rides - most of my rides are "training". I have an SRM on my road bike(s), a Garmin Edge on my mtn and cross bikes and I just picked up a used ti hardtail (v-brakes) so I can run a powertap hub for off-road training and racing. I might try using a powertap during next year's cross season. I daydream about someone making the perfect power meter for a mountain bike with disc brakes. (I don't think anyone's made one yet.)

If I have a good ride but my computer's battery dies, I'm crestfallen. A friend of mine once said to me, "If there's no data, the ride didn't happen." I know it's stupid. :) It's like a video game, in a way.

There's two good blogs about training with power off-road here:

http://teamhealthfx.com/blogs/lynda/
http://teamhealthfx.com/blogs/dave_harris/

Edit: Oh yeah and I'm not that fast. :) But it's fun.

Morgan
 

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morganfletcher said:
I've gone 55mph+ on my road bike plenty. I've been over 50mph off-road on the back of a tandem.
You gotta be kidding, I would have a real HARD time trusting someone else at those speeds :eek:

You up for a 2 day 22'000 feet of climbing trip thru the Sierras in May? Hint: the warm up Climb is Monitor, Oh yea also there will be 22,000 feet of desending :D
 

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TahoeBC said:
You gotta be kidding, I would have a real HARD time trusting someone else at those speeds :eek:

You up for a 2 day 22'000 feet of climbing trip thru the Sierras in May? Hint: the warm up Climb is Monitor, Oh yea also there will be 22,000 feet of desending :D
Assuming I can get a pass from my wife, HELL YEAH. Let me know when you've got dates. The last weekend in May is a no-go for me. I'd like to do the CCCX race on 5/19 too.

The tandem was piloted by Steve Gravenites, who I trusted. I was young and stupid too. The funny thing is that the descent was on a fire road with the nickname "Velocity". The tandem was a Potts with rollercam rim brakes, Steve had me squeeze water from a waterbottle on the rear rim a few times during the ride, to keep the tire from blowing off!

Morgan
 

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morganfletcher said:
The tandem was piloted by Steve Gravenites, who I trusted. I was young and stupid too. The funny thing is that the descent was on a fire road with the nickname "Velocity". The tandem was a Potts with rollercam rim brakes, Steve had me squeeze water from a waterbottle on the rear rim a few times during the ride, to keep the tire from blowing off!

Morgan
Morgan, you squeeze life for all its worth. What a great story.

I guess I have trust issues. No 63mph on a tandem with rollercam brakes for me, even if Steve built it.
 

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Some speedy spots in east bay

Ok for road the fastest spot was Patterson Pass road from Livermore to Tracy I hit 54MPH for one mile stretch, friend on recumbent hit 63MPH. I also hit 48 MPH on Dublin Canyon Road going from Castro Valley to Dublin. I hit 49MPH on Longview drive in Pleasanton both MTB and road, can go probably faster but it is a T and has stop sign at the bottom and a lot of traffic on the cross street.
For MTB I hit 43MPH at Pleasanton Ridge many times on Foothill side. I hit 41MPH on Coyote Hills in Fremont. Crashed at Pleasanton Ridge at around 33MPH, was out for couple of minutes, thanks to my helmet survived.
I do agree that crashes on the road look a lot more dangerous then on the trail, though I crashed more times on the trail then on the road.
 

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Discussion Starter · #18 ·
Going over Sonora pass, Eh?

TahoeBC said:
:thumbsup: Cool, I'll update you as things firm up

Sonora pass Eh? So that would be over Monitor to 395, to and over Sonora pass from the "easy side";) . Then where, to get your 22,000 ft of climbing? Better eat your Wheaties.
 

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jms said:
Sonora pass Eh? So that would be over Monitor to 395, to and over Sonora pass from the "easy side";) . Then where, to get your 22,000 ft of climbing? Better eat your Wheaties.
Spend the night in Sonora, then down to the low point of Parrots Ferry Bridge over to 4 then up Pacfic Grade and finally Ebbits. 22,000 is a rough estimate never actually measured it exactly, but I think it's close, at least it feels like that much ;) I've done it a couple of times.
 

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Thought it was just Old Age

For me, using the calcultor, the highest speed I routinely probably reach is right @ 43-45mph when I drop down Bonny Doon Rd on my road bike. 120rpm [actually I'm not

I know I don't descend like I did 10 or 12 years ago in either the road or the dirt. I don't crash as much either. I remember back in 1990 or something, my avocet read 51 on Bonny Doon Rd. The Topeak Comp 150 I have now barely reads 40 in the fastest parts of that road now. I just chalked the 11 mile an hour loss to old age. Now I think I may have calibrated the avocet wrong and the Topeak is more accurate. Either way I'm grabbing my brakes sooner than I used too and I don't really feel that guilty about it either.
 
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