1989Pre 

Smontanaro: Thanks for that perspective. I am new to tubulars (just this year), so am still learning. The roads around here are very smooth, well-maintained and very clean. My town is 20,000 people and it is the largest town in Maine, so basically, I am usually riding in places that are pristine and have a minimum of motor traffic. One interesting (and humorous) story: I was pumping my tubulars up to 130 with my floor pump and it literally blew a gasket...across the room. So, I had to use my frame pump, and I got about fifty pounds into it and went riding...and it seemed perfectly fine! Only fifty pounds! Oh, these tires are 700x25. Will lowering my pressure to 110psi (where I run my clinchers at) prevent punctures? After yesterday, I'll need a good reason to back off of 140psi.

79pmooney

I only changed the bolding in your quoted text. I've got 25 years and a lot of miles on tubulars and never, ever run more than 120 psi and that was just once. Labels have said my tires were good to 175. That's saying the cord is good and strong and the stitching quality is excellent. I like. But I see no reason at all to shake my fillings out at those pressures.

The term "road buzz" has been around a long time. It wasn't considered a big deal back then but you did drop your pressure a little if you knew that's what the pavement was going to be.

MooneyBloke

Then why did you talk about inflating to 130 and 140 psi as though this was desirable? I run 100 in the front and 110 in the rear with 23mm tires, and I've given some thought to dropping ten psi in each.

By road buzz I mean the sensation you get running tires at very high pressures over garbage surfaces like the all-too-common-in-my-neck-of-the-woods chip-seal paving.

There's a section of one of my usual loops with about 5km of chip seal with smooth pavement on either side. It's getting a bit more packed in now, but with my usual inflation, if I kept my effort the same, there was about 1.5kph drop over the chip seal. Maybe a lower inflation would have helped.

The only place for very high pressures is a board track, and few of us are riding on those.

MooneyBloke

An outing on track?

79pmooney

One of my early road races on my brand new and best ever tires. And like I said, I never went that high again.

MooneyBloke

Even crit corners with tires jacked that hard seem sketchy. /me hates crashteriums.

1989Pre 

I am not telling anyone what to use for pressure. I do not know any of the pertinent facts about you, your environment or your riding that I would need to make accurate recommendations. I am glad that you have found a psi that works consistently-well for you. I do not experience "road buzz". I do not experience dental problems from riding. These hypotheses are just assumptions and hyperbole, Not grounded in fact or informed by personal details.
Does anyone else want to take a shot at why I should not use 140psi?
I'm willing to listen, but I do not get whatever vibration you may be getting. Ok, that makes a little sense to release some air when I know rough or wet or frozen roads are ahead.

MooneyBloke

In that link I sent you (I suspect Silca knows a thing about race tires and pressures), there are some graphs plotting power against tire pressure for various road surfaces. The short of it is that on realistic road surfaces, beyond 100psi, you are wasting watts on less than perfect pavement. The illusion of being faster is precisely that, an illusion.

Pay special attention to the deviation between real world measurement and theoretical results here: https://web.archive.org/web/20200818...12513883533956

1989Pre 

Yes, I have read that article as posted earlier in Bike Forums. For all intents and purposes, the pavement up here is well-nigh perfect. Anyway, thank you for sending this article. You assumed that I was riding on imperfect roads. Never assume. Always ask questions if you do not know. Making a wise-guy comment like "road buzz is not speed" may just cause conflict.

MooneyBloke

All I can say is wow! I think I'm more or less done with this place.

By the bye, we are all riding on less than perfect pavement. That's the damn point.

smontanaro 

1989Pre I have a fragment of a memory which I want to attribute to Jan Heine, but can't find the reference for just now. It goes like this.

To determine the maximum pressure for a clincher tire (the number molded into the sidewall), pump the tire up until it blows off the rim. Divide that pressure by two and publish it as the maximum tire pressure. Again, I couldn't find a reference for that story, but that's what I recall reading sometime in the past 5-10 years. It might have been Jan Heine (Renè Herse). Maybe it was Josh Poertner at Silca. In any case, assuming I haven't completely misremembered, it demonstrates that at least the max pressures has little, if anything, to do with performance. It's just low enough to provide a large safety factor.

Assuming such nutty procedures are used for clinchers, something equally performance insensitive is probably used for tubulars. Remember, lawyers get involved when considering product liability.

pastorbobnlnh 

If you could only come to realize how off-putting your comments normally sound.

Instead of criticizing, judging, and telling a member they are wrong or foolish, why not begin by asking, for example, 1989Pre : "I've never inflated my tubulars to that high of pressure. My roads are rough and uneven. Did you experience any discomfort riding them in the 130-140 psi range?"

I don't expect you will notice the civil difference between how I phrased my question and how you normally phrase your comments. It's also interesting how defensive you become when a member pushes back at your lack of decorum or points out a correction to a statement or assumption you've made.

Now back to our normally civil Totally Tubular content!

1989Pre I've been running my Clement tubulars on my Schwinn 974 at approximately 135psi and really enjoying them. My ride takes me on new asphalt, cracked asphalt, chip-seal, and a concrete MUP with miles of relief and expansion joints. I don't know, maybe it is the expensive Effetto Mariposa gluing tape I used to mount them absorbing the less than perfect pavement, but I'm not experiencing any dental issues or discomfort.

DiabloScott

Not me. But I would suggest you try riding at 80-90 and see if you like it. Not just because your pump broke but a real ride on roads you know well and purposefully used the lower pressures. Make your choice from a real comparison test ride rather than just the way you've always done it.

I used 22mm tires with high pressure in my criterium days; and I was a hard convert to lower pressure and wider tires... but now I like it a lot.
For me it's not about power output or road buzz, it just feels nicer and I feel more confident carving my line in the downhill hairpins of imperfect pavement I ride all the time.

Sedgemop 

Does seem like we're being nudged into tubeless. Not ready to go that direction just yet.

1989Pre 

That sounds reasonable. I mentioned in one of my comments, above, that I rode a short (7M) ride at 50psi and found it perfectly acceptable. I've been using 130psi for most of the summer. I'm listening to what you are saying, but will probably do a few more rides at 140psi and then drop to 90psi, just to see the difference. I can see that adjustment paying off when the roads get harder in the cool weather. Side note: I did feel like I was riding on air or hardly touching the ground when I used 140psi on my last ride. I did not feel anything un-desirable, but thanks for the good suggestion. I think some flexibility is probably in-order.
p.s: That is one cool photo! Don't blink!

79pmooney

Thanks Scott! That photo takes me back a few years! Early '80s when I lived in Alameda and had to climb Pinehurst to get there.

Classtime 

I weigh 155 and I run 110psi in my 22mm Continental Sprinters. If the roads are rough like EroicaCA or The BWR, I run 90 in my Sprinter Gatorskins.

1989Pre 

MooneyBloke, I have indicated, several times, the condition of the road surface(s) I ride on. Please point specifically to the statement I made prior to and provoked your comment "Road buzz is not speed" that you found discourteous. I will apologize for it.

Het Volk

Why are people caring what tire pressure other are running? Jan Heine has cursed us all.

DiabloScott

This one's just for you.


I downsize all my blog photos so people see them on their phones easier - so not high-res, but I love when people comment that they moved away and miss Diablo and my photos bring them back.

Just to keep on topic, here's me on my 22mm 120psi CGs and GP4s and SR hubs.

1986

smontanaro 

I don't think Jan has been a curse on the cycling community. He and Josh Poertner applied more rigor to the evaluation of a very complex setup (pressure, diameter, volume, weight, aerodynamics, ...).

That said, I rode very high pressures BITD. I was 20 pounds lighter, rode much skinnier tires and probably rode on better pavement than I do now. I'm a convert to lower pressures and sometimes encourage others to consider letting a little air out of their tires and see how it feels.

Het Volk

it was in jest, but tire pressure is melting people’s brains

1989Pre 

My only point was that I enjoyed the ride. I thought I would invite others to join me on that.

"I'm just going to say what the kids say: Whatever. Whatever!"

-Paul Blart, Mall Cop-

79pmooney

I remember that stretch of road but not those yellow lines! Nor those rude yellow bumps. And second photo, half the brake cables out in the wind, half buried. I went buried about that year and never looked back.

I wanted that in 1977. Used to dream of being able to drape my palms over the hoods on my many long days in the saddle. That and have shifters my knees wouldn't hit. 42-13 going up 20% walls got old fast. Now, my '83 Pro Miyata is about to ride Cycle Oregon with hidden brake cables and SunTour Symmetric shifters. But I've learned the hard way - if I am not careful I jam my fingers hard on the front tire when I reach for the shifters. That bike has little tire clearance. I've gotten very spoiled going for my longer Superbe levers on my fat tubes ti bike with fender clearance for considerably bigger tires. I'm getting too old to just suck it up and do bone jarring jambs every day. So the bike now sports a "twig guard" under the DT to keep those flesh and blood twigs off the tire.

And to the thread topic - tubbies! Yes, they're on. To that first photo - I've never ridden Mt Diablo on anything else. (I'm bring a lot of tires because it's a pretty good bet that there will be no other tubulars among the 1000 or so of us. And 24c is the absolute max this bike can handle in back. 25s only spin about two revolutions. (I could take the rear brake off. Naw.) The mechanics might bring one pair but I doubt it. Right now I have the front, a 25c VItt G+ glued to a GP4 with the Tubasti Carbone glue, the rear 23c taped with Jantex. We will see very real descents I will have little knowledge of but I am a 70 yo riding with considerably less zeal than I did 40 years ago. Comments guys? Should I change either of those systems? (The Jantex is the first tape I have used in 47 years (when I rolled a tire off the old Jantex rim tape). I love how the tires mount on this new stuff. So easy to get the tire as perfect as it is made!

DiabloScott

Interesting turn of events here - on Amazon I bought what was advertised as "Continental rim cement, box of 12", for about $18 total. Then I received a single tube of glue, filed a complaint, and they refunded the whole amount... so I got one tube of free glue.