IAmSam

Sorry for non-Compass content but...

I've been saying around here for years that Veloflex are freaking fantastic tires (although I use the 23's ) that can't be beat for the money

BTW - for anyone likes colored rubber in 23mm, here's a great deal...

Veloflex Master 23 Folding Road Tyre | ProBikeKit.com

Or if you prefer black 25's and buy your tires in sets of 3 like I do - get the $80 deal...

Veloflex Master 25 Folding Road Tyre | ProBikeKit.com

nightfly

Veloflex look nice. Wish the sidewalls were black...

noglider 

I recently read an article that said that Vittoria Voayager Hyper tires were way ahead of all others. I happen to have a set of 35s which measure 37. They're nice, and their amazing qualities are just now becoming evident as I experiment with lower pressures. I haven't filled them in a month or two, so I'll measure them. I expect the result will surprise me. I might be under 30 psi now.

cDiff Notorious

veloflex black sidewall

They also sell tubular versions

SquidPuppet

Have you ridden them that low? Or, what do you think is the lowest you've ever ridden them? And how much do you weigh?

noglider 

I'll clarify. I think they are at 30 psi or below now, and I rode them that way yesterday. I weigh about 155 lbs. The bike weighed about 30 or 35 with luggage etc. It was a luscious ride, and the tires didn't bottom out.

SquidPuppet

Man that is LOW. I read a rolling resistance test on those and they scored incredibly well.

hairnet

Could have been a shard edge, idk it was like 1am. At least I had a spare

Wspsux

I LOVE Compass tires. I ride Barlow Pass (38mm) on my Salsa Vaya and everything you say I can agree with. As far as outfitting your clunker with them? Well, I did just that. My 650b conversion trek 460 which lives outside chained to a pole wears the Barlow Pass 38mm. If anything they ride even better than their 700c counterparts. Both tires had been slashed with a knife one night. I was ******** pissed. However I mended them with some super glue and a Skittles wrapper, they ride good as new. I find my pressure sweetspot is 40 psi on my 700c and about 30 of my 650b.

I'm completing an 86 Pinarello Montello Build- I plan to squeeze their 26mm tire on there if its tubeless compatible. SLX and those tires could be butter baby!


Both of my sets are the extra lights fwiw.

SquidPuppet

How much do you weigh?

Wspsux

At current fatty weight I'm 180.

SquidPuppet

And 40 PSI? Wow. Seems low. I have the 35mm tire but my rims are very wide so the tire measures a little over 37 and I run 75 PSI rear and 50 front. I think I'll do a little more experimenting.

ThermionicScott 

Yow. Are you, um, large?

I run 40/50 in my 38s and about 35/40 in my 42s and it feels perfect.


ETA: I = 150-160 lbs.

SquidPuppet

Um, no. That's why I'm surprised.


I've always run way below max rated and considered myself to ride tires on the mushy side compared to most people. Either you guys are taking soft to a new level or it's time to check my gauge.

ThermionicScott 

Could well be your gauge! Frank Berto said that they read high as they wear, and start to become less accurate faster than we realize.

That said, I know Jan doesn't use more than 50psi in his, and is content to let them get down to about 30 before re-pumping. One thing about these 38-42mm tires on road (erm, and FG/SS ) bikes is that it's nice to get back to the low-maintenance aspect of the MTBs/cruisers/BMXes many of us started with.

SquidPuppet

The more I think about it, it must be the gauge. I can easily depress the tire with my thumb, and when I sit on the bike and look down I can see a generous amount of deformation at the rear contact patch.

I've also read that you should use a gauge that it's max capability is at about where you run the tires because the farther you get away from the gauges max, the readings become progressively less accurate. According to what I read it was significant too. Mine is an old 160 max. Doh!

jdoff

Echoing this strongly. I have them in 32mm, which measure around 35mm on Velocity A23 rims if I recall correctly. Fast, grippy, and very comfortable. They seem to be wearing pretty well too. I expect to get at least 1500 miles out of them.

Pretty nice deal on them at Planet-X right now too: Vittoria Voyager Hyper Folding Tyre | Planet X

dim

fitted my 2 inch Schwalbe Marathon Supreme today on my MTB .... they are wide (look like motorbike tyres) ..... a lot faster than the knobblies that were originally fitted

I will definately get Compass Rat Trap pass next time

noglider 

Paging @FBinNY. He said something to the effect that measurement instruments are generally most accurate in their middle third of their capacity, which makes sense to me. If you aim to run 60 psi, you want a 120 psi-max gauge, in theory, because you want to read between 40 and 80 most accurately.

SquidPuppet

Hmmmm. I'm working off an admittedly rusty memory here. Let me see if I can find that article.

SquidPuppet

Getting old sucks. Memory is toast.

You are correct. And my memory of the significance was wrong too. It's only slight.

From Accu-gage's site...

TimothyH

I ran the gauge calibration lab for a manufacturing facility for a while. Everything NIST traceable to prove that a second was a second, a degree was a degree, a PSI was a PSI and when a conveyor said it was running at 1 foot per second, by God it was.

In general, a gauge is less accurate at the extremes. The middle third rule may or may not be true depending on the device. Not all measuring instruments are the same. The only way to know is to calibrate.

Accuracy = closeness to the truth.
Precision = repeatability.

A measuring device can be highly precise and wildly inaccurate. Repeatablity is key with bike tire gauges. You don't need the same accuracy as an aircraft guage. Remember the Concorde crash in Paris? Inaccurate tire pressure and one tire blew, shredded and went into the wing... We are not transporting 300 passengers at 500 MPH on bikes.

Bottom line - probably $85 to calibrate a pressure gauge at a decent calibration lab. They will give you a cert and some data on +/- uncertainties.

noglider 

I suspect a good way to check a gauge's accuracy is to compare it with two other gauges and then interpolate.

The only gauge I use is the one built into my cheap floor pump. It may be inaccurate, but it's good enough to give me pressures that feel right and don't cause pinch flats.

FBinNY 

You rang?

Gauge accuracy is expressed relative to the scale. A gauge rated with a 1% accuracy means it's 1% of the overall scale, not the reading. So 1% on a 0-160psi gauge means it's accurate to ±1.6psi, and a 0-30psi gauge is accurate to ±0.3psi.

This rated accuracy usually applies to the enter of the scale, with fall off to both ends. Also gauges repeatedly used to the top end of their range, will suffer some wear and tear, and lose calibration over time (a slow process).

So, the right gauge for tires at 100psi or so is 0-160, though a 0-120 will be OK also. (center scale of the wider scale is probably as more accurate than end scale of the smaller range). Those riding tires at 40-60psi would do better with a gauge that tops out at about 100 or so.

A decent rule of thumb is to select a gauge with a range roughly 1.5-2 times the target pressure.

EnzoRWD

I've got masters and corsa on some of my bike. The best road tire I've ever used, and ride every bit at nice as a tubular. They wear rather quickly, and are susceptible to tiny cuts in the rubber, but I have only flatted once.