pdlamb

Another thread on tire pressure got me thinking. I've read several articles by authors who will release tire pressure when they come to a gravel section, and pump the tires back up when they get back to pavement. So what's your plan on mixed-surface rides?

Steve B.

Keep riding. It’s a rubber tire, it and I can adapt to the trail/road surface.

Eric F 

Really?? Riding with someone who did that would get irritating really quickly.

obrentharris 

I increased pressure once on a ride that began with 35 miles of gravel followed by 40 miles of pavement, but otherwise I don't bother.
Brent

JSchmoyer

I've thought about it. From my house I have 10 miles of road riding to get to gravel. Even then the gravel is interrupted by paved trail sections.

So i am always looking for that compromise set up. I have let air out once when i reach the grav. But stopping to pump back up is a real effort - my hand pump is not fun to use past 30 psi!- so have not done that yet.

I tend to find myself on the gravel with tires that are a bit too skinny and higher pressure (because I dont like feeling slow on pavement).

justin1138

Sometimes I'll dump a bit of air when I get to the trailhead... Sometimes...

MattoftheRocks

Depends on the bike & trails. 99% of the time I’m on 28mm’s and don’t change anything.

If I’m out with the 60mm tires, it’s usually an all-day ride or all-week camping & shredding and I crank them up for >45mins of road and drop them when the trails get hairy for what looks like is going to be more than an hour.

mstateglfr 

I do not adjust my tire pressure mid ride. And I would not ride with people who adjust their tire pressure mid ride.
I don't own a frame pump that I trust to consistently read psi to the small amounts that I would want to adjust.

I mean...how much faster will I be on pavement with 5psi more in the tires?
.ost of my solo rides are 40-60% gravel. And I flip between paved and unpaved probably 5 times.
Genuinely can't imagine adjusting pressure once, much less over and over.

79pmooney

I've done rides where it is 25-35 miles to the gravel. I leave the house at ~70 psi, drop to whatever is right for the condition, then pump back up for the ride home. Doing 50-70 miles on 30 psi or less is work I just don't want to do. Not when I can ride in style for the expense of 5 minutes of pumping. (Granted, I might change my ways if I had to use a minipump.)

SoSmellyAir

Did they learn this technique by analogy to the Dick Cepak tires on their monster trucks?

Koyote

I've only seen this once, towards the end of a long hill climb competition. It was a points ride -- first one up each hill got the most points, etc. We got to a hill that started out paved and then sort of fizzled out into dirt and grass and rubble...At the bottom, a couple guys reached down and pushed in their Presta valves to let out a bit of air. Nothing precise about it.

jonathanf2

I just use the Silca tire pressure calculator to determine best tire pressure prior to a ride. Having to mess around with my tires mid-ride is annoying.

hayden52

I carry both my road bike and gravel bike with me and change according to the terrain. No need to change tire pressure as each one is calibrated properly.

SoSmellyAir

How do you carry one bike while riding the other?

Eric F 

He wasn't being serious.

pdlamb

Hard to tell sometimes. There were a few threads a couple years ago on how to ride one bike and steer another (useful to get the second bike home from a shop). And there was a spoof ad a few decades ago about the Ford Gargantua, which had a spare Explorer on the roof in case you had a flat tire.

SoSmellyAir

I know.

I would rather get a ride to the shop. When my son was in elementary school, there was another dad who (1) rode with his child to school, and (2) rode home one handed while holding on the child's bike with his other hand. Looks kind of iffy, especially given that the school was on a fairly busy street with additional traffic from all the parents dropping off their kids.

msu2001la

I’m ride with a group that has a few who like to “air down” when we get to the gravel.

Our paved road ride to that point is maybe 6-7 miles and we don’t really go that fast. They also never air back up on the way home, which usually has longer stretches of paved riding due to the route we take. Also no one ever has a gauge - it’s just “psssst pssst psssst” at the last stoplight before the dirt and then we’re off.

I always worry that I’ll let too much out and then smash a wheel on a rock/root.

79pmooney

This is a very good reason to use frame pumps, not minis. A good frame pump goes on and off the bike fast and with a locking head, onto the valve stem on and off fast. For an "Oops! I let out too much" 10-15 strokes - done. 30-40 to gety back to road pressure for the ride home.

After 50+ years with Zephal HPs and HPXs, no way am I going back to the dark ages of pumps that only sorta work or one-use throwaways. (Now, trying to get one of those pumps on a modern CF bike is a challenge I haven't tried yet. I'd probably settle for the left seatstay though I really don't like it.)

lasauge 

Like others have said, when I have more than a little bit of pavement to ride to the start of the dirt I'll start with my pressure a bit high at the start of the ride and then let some air out when getting to the rougher surface. I don't bother adding more when getting back on pavement, but there's no 'cost' to having slightly faster rolling in that initial segment since letting some pressure out takes mere seconds.