20210708 GMR Bicycle Time Attack Notes

TRs for the San Gabriel Mountains.
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Taco
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Joined: Thu Sep 27, 2007 4:35 pm

Post by Taco »

I was going to do a big tour this summer but I got hired, so to keep some shred of sanity I've been thinking of other projects closer to home to work at. One I thought of a few days ago was to see how quickly I could run the standard Dune Ape Bike Squad Thursday Night Ride, the GMR Loop. For me, this typically involves riding from West Covina up to Azusa, taking the 39 to East Fork, to GMR, up backside and down frontside, then back to WC by a series of lower traffic streets. I pretty much always run it clockwise, as this gives you the best and longest stretch of downhill on GMR, 9 miles of it. 39 isn't great downhill, though there are fun parts, they're interrupted by short climbs. I am hopelessly addicted to going downhill as fast as I can, and from a background of driving GMR 'fast', it's a very special place for me. Plus you end in Glendora and The Hat is there! I fucking love The Hat.

An important thing to note is that when doing a time attack (just the Japanese auto racing term for time trial) is that I've taken the shortest distance I can without taking dangerous streets. This means that when I left at 0220 yesterday morning, I could ride up Azusa Avenue cause nobody was on it. This is a mile shorter and a little less gain than my usual side street, which is much more quiet when people are awake and driving around. This also has lights instead of signs, so there are technically fewer stops. I don't mind running a stop sign or red light if nobody is around, but if it's green lights on a north south route as default timing, I can remain in my aerobars, head sorta down, and just generate power and go faster.

I just got back from the second ride of the GMR loop yesterday (it's 0145 as I'm writing this), which we took at a casual pace. This was perfect to establish a baseline time for regular riding, so I know about how long we can allocate for a fun ride. We take longer breaks, talk a lot, hang out, pick up critters, sometimes go soak in the river or whatever we fancy. On a time attack, you just go as fast as you think you can until you're back where you started.

I have only done one time attack on a bike before, which was taking the coastal route from San Jose to Santa Monica, which was like 440mi in 35hrs or so, or 48 total cause I slept for 4 hours in Morro Rock. Point is I'm new to this, so I get to experience the cool early period where you learn big things and the gains are large and it's more exciting than later on where you've been around the block and are using titanium handled toothbrushes with the handle cut off and shaving your pubes just to go 1 nanosecond faster. I have a few big long distance time attacks I wanna do (Pacific Coast Canada to Mexico, and maybe the whole 395), so I gotta get an idea of how hard I can push when going 'as fast as possible' and expect my body to work for 50, 100, 150, 200 miles, and so forth. The GMR loop is 50mi and 4100ft gain or so for me, so I get an idea of how 50 miles with a fair amount of mountain riding will feel, so I know I can push a little here and there, or I gotta back off or whatever.


Here be the numbers:

GMR Time Attack Notes
49mi 4110
Moving Time 3:02:53
Elapsed Time 3:10:15
AVG 16.1mph
Max 39mph

Casual Pace
50mi 4180
Moving Time 4:05:09
Elapsed Time 6:32:52
AVG 12.3mph
Max 39mph


The max speed is identical because I am on new tires. I normally have Specialized Sawtooths, which have a tread pattern with a sorta 'slick' center pattern. The shoulders don't have knobs, so they lean on pavement very well and grip tenaciously. Very predictable and confidence inspiring, and forgiving as well. I've been riding these for a while now and know them very well, so I am very confident entering corners at speed on them. My new tires are Panaracer Gravelking slicks in the same size (650x47). I figured they'd give me incredible grip, better than the ST's, but I am too scared to lean hard on them yet. When I first installed them at work, I went for a spin around the parking lot to distribute the sealant and feel the tires. The parking lot was freshly repaved weeks ago. I made a left turn about 50ft into my first ride with them and they slid out and I slammed onto my left side, bruising my shoulder and thigh, and spraining my hand. Scratched a few parts, shifted my bars over, was a little embarrassed. I got up immediately and kept riding. Granted that's a freshly repaved blacktop surface but I'm still scared to lean. I guess I gotta lean a little more over time... I wanna put new Sawtooths on!!! I keep trying different tires and always come back to them. Let that be a lesson to you young whippersnappers: never change! Just keep using the same old shit cause it works for you, or whatever. I like trying new shit cause sometimes it's better. Anywho, I normally get up to maybe 43mph, not much faster than 39, but I can maintain greater speed through the corners on the ST's. I miss that a lot.

One aside, the powers that be recently (in the last 6 months or so) cut grooves and recessed the reflectors on GMR. I reckon this helps maintenance a lot since there's plenty of rockfall, and the trucks with the scrapers would shear the reflectors off. I gotta bitch as a cyclist cause those things really make the descent more spicy! When you hit em, you better have your bike balanced or you're gonna move in unwanted ways. Danny hit one with his rear tire tonight and it threw him way to the side (no crash, just big shift!). When I hit em while cornering, usually with my rear tire, I can feel the tire move laterally maybe 6-12 inches before it regains traction. You gotta pick just the right line if double-laning so you don't hit the grooves. Sometimes they line up just fine with the fastest line, and sometimes they don't. On the positive side, this just means other roads without these grooves will seem easier.

Tires and descending technique out of the way, I think I can save time next time by not writing anything down on my notepad. I write my time when I reach certain points, but I could just rely on Strava to tell me time. I'll give that a shot. It will save me a tiny bit of time. Putting my headlamp on my helmet before I go out will save a little time as well, and in the conditions present yesterday morning I only needed a single water bottle. I could save the weight of the second one, but I would have to refill at the spigot, which took me 3 minutes... so maybe keep the bottle. I am riding my fat-tire-any-road-bike, so I could ride a road bike and probably save more time. Perhaps that's the next step. This bike is my everyday bike and it fits me like a glove, and it's what I would ride on my other speed runs, so it's valuable for me to continue doing so and making changes that allow me to perform faster without compromising the durability and practicality of the bike.

One thing I enjoyed about the time attack was that I was focused on riding fast, so my mind didn't wander and I didn't settle into any negativity or anything, I just focused and listened to my body and the various aches and pains, and my heart and muscles, and sped up when I could, slowed down and stretched when I needed it. Sometimes the little world illuminated by your headlight in the dark is home to negativity and shit, but this time it was just keeping me focused on forward movement. This could be a good coping tool, as I'm currently a little down in the dumps due to some lifestyle changes after doing the same thing for 3 years straight. I'm not sure I wanna start smoking, though I really enjoy riding somewhere chill and having a cigar, it's an expensive habit and not good for your physical health, etc etc etc.

Anywho, I don't think I have more to add at the minute. I hope you guys find some enjoyment into my mental vomit about bike stuff. Hope you're all doing well and getting out as often as you reasonably can, and finding peace in the mountains and deserts. Cheers
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Sean
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Post by Sean »

When you note your split times how precise is it, down to the minute or second? Perhaps you could just take screenshots of the times on your phone at predetermined spots. And if you can do that while you're riding, you wouldn't even need to stop.
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Taco
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Post by Taco »

When I write my times down on my pad, it's down to the minute, based on my bike computer which is one minute off from my phone/strava. I didn't post those splits on here though. I thought of doing what you said, but I figured I would confuse those times as I wouldn't know which time was which, even though they'd be in chronological order.

I figured maybe I could make my own 'segments' on Strava just for my own use. There are tons of segments on there already that don't mean anything to me, seemingly arbitrary point to point segments from this bridge to that hill or this mile marker to that one or whatever that people have made. I assume I can make my own (if I pay for Strava) so I can automate the process. I will have to look into that unless one of you guys knows if that can be done?
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David Martin
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Post by David Martin »

Thanks for the report. Last Saturday my buddy and I rode from Manker Flat to the East Form / 39 junction and I was wondering about those gooved sections in the road.

Until we got there, we didn't know that GRR was closed to cars for the 4th of July weekend. That made it an even better ride but wow, there were hundreds of other cyclists up there. It was like a road bike freeway.

Our route was mostly downhill but I didn't feel guilty because it was a legitimate chunk of our San Gabriels circumnavigation. (When we finally do the last segment and finish at Kurt's house in Glendale, our net elevation gain will be zero.)

I see that you like The Hat. Ever finished a hike by hitting Handel's Ice Cream in Upland? That place is really special. Their 4 scoop sampler or sundae might net you a calorie gain of zero after a big hike or ride.
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Taco
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Joined: Thu Sep 27, 2007 4:35 pm

Post by Taco »

Don’t ever feel guilty about not going uphill enough!

What’s your route to Glendale going to be like?

I love it when they close the roads, but I’ve never had to deal with lots of bike traffic before. I can imagine the scene. Was it cool or a bit of a mess?

I’ve not heard of that ice cream place. Thanks, now I have a goal, a new place to check out. Putting it on my map.
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