Tire pressure test results

August 16, 2018

Avocet FasGrips were rated for 105 psi. Lowering tire pressure to improve rolling resistance might work on some roads.


I’ve ridden enough miles now to offer some results on what tire pressure works for me, after research indicated it’s better for lowering rolling resistance to run lower tire pressures.

Your results will vary, unless you weigh the same as me and run the same tire and rim. I’m a little over 150 pounds, and my tires are Continental Gatorskin, 28 mm width, mostly, and 36 spoke Mavic Open Pro rims. Even then, there’s personal preference.

I’m told that these rims are old fashioned, but I sure like them. I built my own wheels eight years ago and after 40,000 miles they’re in perfect shape. No wobbles.

I started with 65 pounds rear pressure, 60 psi front. After struggling through 50 miles of riding, I decided this was too soft. The bike felt sluggish and steering was a chore. Believe it or not, that’s the recommended pressure on some charts.

I can’t imagine that this pressure would be adequate under any circumstance, even with wide rims. The Mavic rim is 20 mm, but today’s wide rims run 23 mm outside.

From what I’ve read, a narrow rim and wide tire causes the tire to squirm more than on a wider rim. I can believe it.

I increased the pressure to 75 psi rear, 70 front. That felt good. I have full control over the bike in all situations and it doesn’t feel like the lower pressure is slowing me down.

I’m thinking a pressure of 75-80 rear, 70-75 front is best for me. Of course, you can run higher pressures. I was at 95 rear, 90 front, or higher, for decades and never had problems. Backing off on the pressure might help reduce tire rolling resistance, but at my age it doesn’t matter, much.

Pressured to resolve tire pressure debate

August 11, 2018

What’s the ideal tire pressure? It depends. More may not be better.


Recently I’ve been reading that cyclists are running their tires with too much tire pressure, believing that the higher the tire pressure, the lower the rolling resistance.

The late Jobst Brandt, bike expert, believed this axiom to be true and never questioned its validity. He had another reason to keep his tire pressure high. He weighed a lot and that made him prone to pinch flats. He also rode on bumpy trails.

One lab study in 1999 shows that running higher pressures on tires decreases rolling resistance. The exception is riding on rough surfaces or gravel.

A wider tire running at a lower pressure will do better on rough roads, according to test results reported in Velonews and elsewhere.

Tires themselves have been thoroughly tested for rolling resistance by brand on bicyclerollingresistance.com.

Off The Beaten Path beats the debate into the ground with its analysis. A study done by Frank Berto in the 1990s is cited and is pretty much the first published word on the wisdom of lowering tire pressure for reduced rolling resistance.

Wider tires might improve rolling resistance. That’s another hot topic. At issue with running wider tires is that narrow rims and wide tires are not a good combination, as the tire squirms on the rim much more than on a wider rim. I’m guessing that they mean a rim less than 23 mm outside diameter qualifies as narrow.

GCN, the YouTube bike channel, has run several shows on the topic, so that’s what prompted me to look into it and try out lower tire pressures.

I’ll share my results in a future blog, once I’m done testing.

Cheating old age

July 29, 2018

Bean Creek Road has it all for remote country roads. Cool and refreshing in the morning.


Yes, I took a bus to Scotts Valley this morning so I could enjoy my ride. That means fewer miles.

In the days of yore, we’d ride from Palo Alto over to the coast, then back up Mountain Charlie Road, Summit Road, Skyline. It was a long day. Jobst Brandt led the way and kept things interesting.

Taking the Highway 17 Express from Diridon Station was a close thing. It carries three bikes. I was bike number three. A fourth rider wasn’t allowed to bring on his bike. Rules are rules.

I can’t tell you how much more enjoyable it is riding up steep roads with fresh legs. I could enjoy the climbs without suffering.

Silo house on Mountain Charlie Road.


After the Mountain Charlie Road climb, I can say with certainty that the hardest part is the section before the blue silo house. The Old Japanese Road section is not as difficult.

Summit Road has some stiff climbs, but they’re a shade easier than Mountain Charlie, topping out at 15 percent. The first 0.4 miles after leaving the Bear Creek Road junction have been paved, long sections of guardrail added and hillsides reinforced.

One of the reasons I like this ride is the lack of car traffic. It’s sparse, but I’m seeing more cars than I did 30 years ago.

The real problem with cars in the Santa Cruz Mountains is Highway 9, which has become a gateway road where all the traffic goes. Castle Rock State Park is the biggest magnet. Parking lots keep expanding along Skyline.

I headed down Hwy 9, but if you’re planning on turning left onto Redwood Gulch Road or Pierce Road, hope for a break in traffic. It’s bad enough now that there’s no guarantee you can make a safe turn.

A grim reminder that Mountain Charlie Road needs ongoing maintenance.


All of this reminds me of Marin County and Panoramic Highway. It you want to see the future on Hwy 9, this is it. Panoramic Hwy is lined with cars for miles, everyone trying to get to Muir Woods.

Looking out to the Pacific Ocean and a layer of brown haze reminded me of how lucky we are here. Forest fires are a rarity in the Santa Cruz Mountains, thanks to the fog. Let’s hope it stays that way.

You’re gonna need a bigger parking lot

July 21, 2018

Skyline Boulevard road repair south of Castle Rock State Park. Looks nice.


On what is becoming an increasingly rare occasion, I made it up to Skyline Boulevard to check out the road. This being a Saturday, I didn’t have much hope for minimal traffic, and I was right.

Weekend traffic is becoming so bad on Hwy 9 that the break in car platoons is becoming less and less frequent. So where are these people driving to and who are they? They’re hikers and cyclists going to recreate in our mountain parks.

If I had my way, I’d ban cars in the Santa Cruz Mountains, except for local residents, and make everyone headed to a park take a shuttle bus.

Which leads me to the new visitor center under construction at Castle Rock State Park. Not that I’m against it, but they’re gonna need a bigger parking lot. Visitors are already unable to find parking on weekends. It’s only going to get worse.

Castle Rock State Park’s new parking lot and visitor center under construction.


I headed to see the Skyline Boulevard public works project a mile or so beyond the park. It’s a masterpiece of road repair where a year and a half ago heavy rains washed away the road. I’m sure a culvert was involved. They always are. It looks like it was designed against such a catastrophe. There are actually two repairs, a smaller one close to Las Cumbres.

I heard there was also some public works going on at McKenzie Reservoir, so I headed down that way on Black Road. Sure enough, the road has been smoothed out from lots of heavy truck traffic. San Jose Water is doing something to improve the reservoir’s outlet. The water level is low, although I’ve seen it even lower.

McKenzie Reservoir is undergoing maintenance to improve outlet structures that meet dam safety standards.


Finally, the last public works project was a couple of slides fixed on Sanborn Road.

Road repairs continue from the previous winter’s storms. Schulties Road, I’m told, is being fixed, but I haven’t heard about Redwood Lodge Road’s slide. Cyclists can still walk through, but cars can’t make it.

I’ve only mentioned a few roads that took a hit in the El Niño storms two winters ago. Santa Cruz County has pics of all the damaged roads in a PDF file.

Angel Island no picnic

July 20, 2018

Nice view of San Francisco from south side of Angel Island.


I don’t know where I got the idea, but I always assumed the paved road circling Angel Island was flat. Wrong.

A visit to the island made my bucket list, so we headed for Tiburon to pick up the ferry; it’s a 10-minute ride to the island, which costs $15, plus $1 for hauling the bike. Tiburon is preferable to San Francisco when driving from a distance.

I considered renting a bike, but the cost of the rental, around $50, convinced me the logistical inconvenience was worth it. However, if you’re interested in renting an electric bike, this is a good time to try one out.

With beautiful weather, the bay crossing couldn’t have been smoother. We exited the ferry and I started riding on the fairly steep and unpaved single-track trail that climbs up to the perimeter road. It’s not a very friendly route for a tourist.

What’s odd is that there’s a paved road at the wharf that goes to the perimeter road. I’m guessing the park service doesn’t want to deal with yahoos blasting down the steep paved road into crowds of tourists.

I took a clockwise route so that the view of San Francisco and the Golden Gate Bridge would be my reward on this five-mile loop.

There’s a climb of about 7 percent for a ways before the road levels near the immigration station. A lot of history comes with the island, but I won’t bore you with the details.

The road begins climbing once past the somber-looking buildings of Fort McDowell. The south side of the island has the steep spots. I didn’t sign up for a 16 percent grade, but that’s what I read on my Garmin. It’s followed by a steep descent.

The best views of San Francisco are at the Battery Drew pullout, followed by Battery Ledyard. Skies were clear, so I enjoyed the spectacle.

In less than an hour I finished the loop, after another descent. I didn’t check out the dirt road higher up that circles the island, but based on what I saw of it, it’s best suited for a mountain bike.

While the ride itself is no picnic, I can recommend Angel Island as a place for a picnic.

Maybe in another dimension where bikes rule the land, this island is the site of a bike race. I can see that happening. It would be an interesting course.

View of Angel Island using a heightmap.

San Francisquito Creek flood control project nearing completion

July 13, 2018

Work continues on the trail along San Francisquito Creek in Palo Alto.


I checked out a portion of trail on San Francisquito Creek I’ve used over the years to reach the Dumbarton Bridge recreation path.

It starts at the Baylands Athletic Center in Palo Alto on the east side of Hwy 101. There’s still work to be done, but I can see a high wall along the creek that looks like steel panels. Ugly. It looks like it will be finished by the end of this year.

People who haven’t lived in Palo Alto for a long time may not know that the creek is prone to flooding during heavy, prolonged rains. My friend Jobst Brandt, who lived on Middlefield Road near Lytton, saw his basement flood in the 1980s when the creek went over its banks.

There’s a lot of other work associated with this flood control project.

Old Railroad Grade a rocky road

June 27, 2018

Gerbode Valley was going to be developed into a condo haven, but environmentalists rebelled in the 1960s. Good for them.

I hadn’t been up the Old Railroad Grade to Mt. Tamalpais since 2007, so I decided to pay a visit one last time. Maybe it’s age, but back in 1981 I’ll wager the road wasn’t as rocky.

There’s no denying the grade is rocky. The crookedest railroad in the world, built in 1896, reported 90 percent bedrock. However, they must have used ballast and aggregate to smooth out the road.

After all these decades, rains have washed away the topsoil, and everything else laid down, and now we have bedrock.

Another difference between now and the days of old is that West Point Inn has turned into a hangout for just about everyone living in Mill Valley. It was downright crowded.

The last grind to the summit was in a pea soup fog, so for the first time I was disappointed by the view. Because I was on a road bike, I headed back down Ridgecrest, Pan Toll, Panoramic, Hwy 1. Full suspension mountain bikes have their place, and one of them is riding down the Old Railroad Grade.

I knew Panoramic Hwy could be a zoo on a Sunday, but I didn’t expect it to be quite so bad with the fog. I gave thanks I wasn’t riding uphill.

Rather than taking the crowded Sausalito road back to the Golden Gate Bridge, we opted for Tennessee Valley and Marincello Trail, Bobcat. Because I had never tried the Baker Tunnel, we took Bunker Road, hit the tunnel light perfectly, and blasted through on a fast downhill. So fun.

Old Railroad Grade in 2007. Rocky road.

Bay Bridge sparkles on a bike

June 26, 2018

Bay Bridge path looking west to San Francisco. It’s fabulous. My shadow thinks so, too.


I’ve been on a tear lately, driving all over the Bay Area going on bike rides. It’s not my style, but sometimes there’s no other choice.

On Sunday I tried out the Bay Bridge path from Oakland to Yerba Buena Island, a one-way distance of 2.2 miles. It has been fully open since 2016. I’m impressed. No doubt it cost millions, but it’s a trifle compared to the $6.5 billion cost of the bridge.

Having recently ridden over the Golden Gate Bridge (GGB), I can make a comparison. The GGB is to be avoided after 8 a.m. on the weekend. In the afternoon it’s a zoo. If the crowds aren’t bad enough, it’s narrow. There’s so much equipment on the path that passing riders going the other way is a chore.

The Bay Bridge is wide and I doubt that it sees anywhere near as many cyclists as the GGB. It’s about as scenic a place as you could ask for in the middle of the bay.

Of course the GGB is iconic and I would never discourage anyone from riding it at least once, but be sure to try out the Bay Bridge one of these days. You won’t regret it.

From what I’m reading, a bike bridge/path is planned for the existing Bay Bridge into San Francisco. It will be bolted onto the old bridge. Completion in 2025, so they say. Maybe too late for me.

Sonoma Valley intact, but hills burned

May 31, 2018

IMG_20180523_142723319_HDROn a recent ride to check out Sonoma Valley, I did not realize the surrounding hills were so badly burned in the October 2017 wildfires.

I headed up Cavedale Road, a gnarly, steep climb that’s similar to Old La Honda Road, only steeper in places. Cavedale Road residents took a hit from the firestorm that ravaged the hills. I saw burned trees everywhere, but the fire skipped around, so some spots were untouched.

It’s a six-mile climb at a 10 percent grade, with some steep spots of 16 percent or more, peaking at 2,100 feet. The ride down Trinity Road tested my brakes. It’s about 12 percent the whole way down to Highway 12.

I’ve visited Sonoma over the years, enough to realize that Sonoma and Napa Valley have become commuter havens for people working in San Francisco. The traffic on Hwy 12 and Arnold Drive is unbelievably heavy during weekdays. I can only imagine what it’s like on a weekend during peak tourist season.

The county plan for a bike path along Hwy 12 from Sonoma to Santa Rosa can’t come soon enough.

I checked out the Napa Valley Vine Trail, starting in Napa and going north. Eventually it will extend north for 45 miles, starting in Vallejo.

The trail is nice for staying off Hwy 29, but there’s Solano Avenue right next to the trail, which doesn’t have much traffic. However, the trail cuts through downtown Napa, reducing the hassles of riding in traffic. There’s an impressive recreation path spanning Hwy 29.

Fortunately, you can still avoid traffic by riding up the steep roads in Sonoma Valley and Napa Valley. Just be sure to leave EARLY to avoid valley traffic.

Sign pollution spoils the view

May 20, 2018

Palo Alto has a thing about signs. Not sure we need one in Stevens Canyon.


I don’t think much about signs, until I do, and then I start seeing the pollution. Do we need a city limits sign at the bottom of Stevens Canyon?

I’ve been riding in the canyon since 1979. Over the years it has gotten rockier. This is, after all, the San Andreas Fault zone. Erosion brings down rocks, and over time they accumulate.

Still, I recognized stretches of trail that hadn’t changed a bit in terms of condition. As for riders, I saw several on a Saturday morning. The guy and gal blasting up the hill must have professionals. They were moving.

When I started riding here, Jobst Brandt and friends were the only ones cycling the canyon trail. All we had were road bikes. Those days are long gone.

Along with popularity comes enforcement. Imagine my surprise when I saw a ranger with a radar gun. It wasn’t far from the end of the trail. I stopped immediately and we had a friendly conversation. I wasn’t speeding.

One important change I noticed is that the Stevens Creek crossing no longer has an easier option. It’s overgrown. Now you go down a four or five foot vertical drop to reach the creek. I’m sure some ride off it, but not me.

The single-track section toward the end has plenty of poison oak, so watch out.