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chas

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Reply with quote  #1 
First the tire gets listed in the top 5 on rolling resistance - against some of the top rated road race tires in the world.

https://janheine.wordpress.com/2018/01/31/one-of-the-5-fastest-tire-in-the-world/

Now it gets a rave review from road.cc

Not sure what it would take to earn 5 stars (instead of 4.5), and the reviewer gushed all over these tires - even rating it better than the G-One speed and all around (another set of tires they rave about).

http://road.cc/content/review/237487-compass-barlow-pass-tc-tyre 

Its an interesting review with lots of good technical information

Obviously the Barlow is not for everyone.  Its not a heavy duty touring tire, and probably not something you want to take out on a flinty chunky gravel grind.  But if your priorities are speed and suppleness - they seem to be at the top of the heap.

I don't own a pair of barlows, but these review make me curious...  

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dangle

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Reply with quote  #2 
Did you see the pressure used?? 87 psi for a 35mm tire? That's absurd. Half of that is still too high for a lot of users doing true gravel riding. The 'rolling resistance' argument completely goes out the window if you tried to correct for casing tension and brought them down to an equivalent casing tension as seen in those smaller road tires.

Flo had a good write up on casing tension. I can't imagine there's too many rims even strong enough to sustain a tire that big at that high of a casing tension for very long. Read a rim's "max pressure" notes and you see the max pressure goes down as the tire size gets larger. If you follow the Flo formulas, a 35mm tire at 6 bar/87 psi is equivalent to a 25mm tire at 130+ psi. That's bonkers and not something you would want to ride for very long. 

Scroll down in the first link to the comments where a rolling resistance expert (Tom A./Tom Anhalt) chimes in with good information.

I'm not saying the Barlow Pass is a bad tire, but some people are clearly ignoring science for marketing.
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Jim_H

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Reply with quote  #3 
I've used various sizes of Compass tubeless "Extralight" tires (28mm up to 42mm, including BabyShoe Pass 650b).  They are truly wonderful tires.  Super fast and supple.  I use them on my commuter, and have a set on gravel wheels that I use on rail trails and faster fire roads.  

I agree that they are probably more suited to light gravel and asphalt, but I do know people who  race gravel on them and swear by them.  I think some of the appeal would be lost if you were trying to ride them on rough terrain were super low pressures were needed.  There are better tires for those circumstances.

They also aren't great in slimy mud (no knobs), as they can get squirmy.  

They are what they are, and are awesome tires, but cyclocross tires they are not.
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chas

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Reply with quote  #4 
Quote:
Originally Posted by dangle
Did you see the pressure used?? 87 psi for a 35mm tire? That's absurd. Half of that is still too high for a lot of users doing true gravel riding. The 'rolling resistance' argument completely goes out the window if you tried to correct for casing tension and brought them down to


What I read in the road.cc article was:
"Extrapolating the go-to Berto chart of tyre width vs. optimal pressure for 15% drop, the target was around 35psi – but going 5psi lower felt no different."

"Compass is strident in advising that its tyres should not be run beyond 60psi tubeless(link is external), although on the casing it says 75psi, "


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chas

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Reply with quote  #5 
Ah, I see, you were talking about janheine article discussing the TOUR test.  Given that you can't read the TOUR test without subscribing to the Magazine and speaking German - I think the road.cc test is more userful.

From janheine's blog, Tom Anhalt had some good info.   From what I have seen tested - there is a very very small reduction of rolling resistance at high pressure for high end tires.  If I'm doing a velodrome or crit race I'm on skinny tires and high pressure.  In non ideal race conditions, I'm on bigger tires at a fraction of the pressure.
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Volsung

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Reply with quote  #6 
Quote:
Originally Posted by chas


What I read in the road.cc article was:
"Extrapolating the go-to Berto chart of tyre width vs. optimal pressure for 15% drop, the target was around 35psi – but going 5psi lower felt no different."

"Compass is strident in advising that its tyres should not be run beyond 60psi tubeless(link is external), although on the casing it says 75psi, "




I would go even less if you're setting them up tubeless. My last set of Compasses started exploding off the rim around 40-50 psi which is about what it takes to get the bead to seat.

And if you do get these and set them up tubeless, WEAR EAR PROTECTION. I have to yell that because of the damage caused from my last Compasses.
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bobknh

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Reply with quote  #7 
My $.02. I normally start my comments by apologizing for my lack of gravel experience. Having put several thousand miles on 2 pairs of 35 mm Bon Jon's extra light casing, one pair with latex tubes, the other tubeless, I feel more confident of my opinions. When it comes to running on packed dirt, mild gravel, and pavement, these tires are remarkable performers - in a class with my old racing tubulars in feel and performance. But all of this comes from the very supple casing. If you are going out to ride a mix of pavement and maintained dirt roads, with just a bit of rougher stuff thrown in, then you couldn't grab a better tire. But, all of this performance comes at a cost. The supple flexible casing is both more difficult to install tubeless, and will suffer from sidewall fatigue due to the constant flex of the sidewalls, as well as more vulnerable to cuts and scrapes from road debris, and sharp stones and chunky gravel. If your riding tastes lean toward more challenging surfaces, then the Compass tires may not be for you. If however, you want a tire that can give the feel and performance of racing tubular, and you ride mostly on maintained dirt roads and pavement, the Compass tires may be your ticket.
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Elgar

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Reply with quote  #8 
I used the Compass Snoqualmie pass at 44mm width in all my gravel racing last year. Ontario Canada. I did the Eager Beaver 100 miler and El Diablo among others. Pressure was about 25 psi. These "Gravel" races had all sorts of road surface form smooth asphalt to baby head rocks and single track. Also lots of sand. I was worried a little at the start because the tires are esentially slicks with some straight file thread. They were awesome on everything except mud. The mud sections were short and I was able to get through fast enough for it not to be a problem. There were sections full of large loose rocks, some sharp. There were 20 or more people fixing flats at the end of some of these sections. I sailed through most comfortably. I just bought two new Stellacoms to use in the P2A race this spring. Usually lots of muddy sections. The Stellacoms have large knobs but are supposed to roll well. The Snoqualmie pass tires were claimed to roll really well, and they did. Several riders talked to me after the race. They were behind me on descents and were amazed at how I rolled away from them without much pedaling.
I am 190cm tall and weigh 84kg.
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bobknh

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Reply with quote  #9 
Quote:
Originally Posted by Elgar
I used the Compass Snoqualmie pass at 44mm width in all my gravel racing last year. Ontario Canada. I did the Eager Beaver 100 miler and El Diablo among others. Pressure was about 25 psi. These "Gravel" races had all sorts of road surface form smooth asphalt to baby head rocks and single track. Also lots of sand. I was worried a little at the start because the tires are esentially slicks with some straight file thread. They were awesome on everything except mud. The mud sections were short and I was able to get through fast enough for it not to be a problem. There were sections full of large loose rocks, some sharp. There were 20 or more people fixing flats at the end of some of these sections. I sailed through most comfortably. I just bought two new Stellacoms to use in the P2A race this spring. Usually lots of muddy sections. The Stellacoms have large knobs but are supposed to roll well. The Snoqualmie pass tires were claimed to roll really well, and they did. Several riders talked to me after the race. They were behind me on descents and were amazed at how I rolled away from them without much pedaling.
I am 190cm tall and weigh 84kg.

Thanks for the feedback. Did you use the standard or extra light casing on your Compass tires? My experience with Bon Jon's was with the extra light casing. For racing on unpredictable conditions perhaps the standard casing holds up better. Also, did you mount your tires tubeless? I found that it was vey difficult to mount my extra light BJ's tubeless; and required extra sealant before they reliably held pressure. The sealant was actually leaking through the casing. After several days of TLC, the casing sealed up -- but it took a lot of TLC and patience.
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LewisQC

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Reply with quote  #10 
Quote:
Originally Posted by Elgar
I just bought two new Steilacoms to use in the P2A race this spring. Usually lots of muddy sections. The Stellacoms have large knobs but are supposed to roll well. .


A quick review of your Steilacooms for P2A would be appreciated... I want to do this race next year (cannot this year due to injury) and will need a set of mud tire (Steilacoom vs GK Mud)
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Elgar

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Reply with quote  #11 
I used the regular weight casings mounted tubless on a set of Stan's carbon fiber Valor rims. I had no trouble mounting and sealing them. I used a regular floor pump and Stan's sealant, amount as suggested on the can. No weeping through the casing and very little if any pressure loss over a month of use, until I switched to cross tires. These were WTB Cross Boss TCS light in 35mm width. Now these did leak through the casing (must be the light) but other than ascetics did not pose a problem. Just a quick wipe.
I haven't tried any of the light Compass tires. I'll sure let you know how the Stellacoms work out!
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tomasumter

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Reply with quote  #12 
I got sold the Compass koolaid when I first acquired my gravel bike: Barlow Pass, gum walled in standard casing. I went for a while with no issues (2-3 months). Then I started getting flats, eventually a side wall cut. Replaced that tire. Replaced a second tire. Decided to try tubeless; they don't do tubeless very well. The last time I went out on them I started out with a tubeless setup (it had been working okay for a couple rides) two tubes in my kit and came back with both of my tubes used plus my buddy's tube. 5 flats, a quarter sized gash on one and a 'minor' cut on the other, I am lucky I made it out. In fact when I think of some of the places I went before I knew they sucked, i thank my lucky stars I had buddies with me that day. The Compass are really great when they're good, but they are not tough at all, so be aware. This all happened in 2015, and I had more flats on those dumb Compass tires than I've had total in the 2 1/2 years since, spread across 3 bikes.

I have to say, as part of their attempts to provide customer service, they gave me a pair of Chinook Pass (700x28) that I used for a spring/summer on my daily rider. They were very enjoyable to ride on. I tried to be very vigilant where I rode, but I only had a single puncture on that set. The ride quality was much more refined than the Contis I was used to. I only ended up pulling them when I switched to a winter/rain tire for the rainy season.

Tires just shouldn't be this difficult. I want a tire I can trust. I'm a huge fan of the Teravail Canonballs (one flat in 2 years, they are tough and seem fast), but there are many other great tires out there. There is no need to rely on a fighter with a glass jaw.
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bobknh

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Reply with quote  #13 
Quote:
Originally Posted by Elgar
I used the regular weight casings mounted tubless on a set of Stan's carbon fiber Valor rims. I had no trouble mounting and sealing them. I used a regular floor pump and Stan's sealant, amount as suggested on the can. No weeping through the casing and very little if any pressure loss over a month of use, until I switched to cross tires. These were WTB Cross Boss TCS light in 35mm width. Now these did leak through the casing (must be the light) but other than ascetics did not pose a problem. Just a quick wipe.
I haven't tried any of the light Compass tires. I'll sure let you know how the Stellacoms work out!

Thanks for the additional info. For gravel riding, I would definitely go with the standard casing with Compass tires. I'm done with the extra light casing. For me, it just isn't worth the hassle installing tubeless, and reduced durability. 
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chas

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Reply with quote  #14 

Interesting feedback everyone.  That makes sense.  Those sidewalls are designed to be supple, not strong.  Not sure what they use for protection along the tread. They seem to be on par with a race tire, not a gravel tire. 

Most of the dirt roads around here don’t have much chunky gravel on them, but when they do get graded, the fresh chunky gravel can be pretty hard on sidewalls.

 

I don’t recall them really having tubeless tires until the last year or so – although that may just be a change to the tire bead rather than the tire themselves.

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Slim

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Reply with quote  #15 
Yes, Compass has been adding tubeless version of their tire steadily in the last few years. given their super thin construction I would absolutely not mount a Compass tire tubeless if it was not explicitly rated for it.

Regarding the original postings about rollling resistance: if anything, the super thin casing and rubber layer on Compass tires, will further help reduce rolling resistance at lower pressures. at high pressures, the rubber compound matters more, but as you drop presssure and deform the tire, suppleness starts to matter more.

Keeping that in mind, I have always thought that Compas tires are probably some of the fastest tires for hilly gravel rides, due to their low weight and supple casing. On pavement, at higher pressures, others with better rubber compounds might be faster.
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chas

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Reply with quote  #16 
I set up some thin sidewall tires tubeless.  Yeah, took a few days to get it to seal nice and good, but it has worked well since then.  Tires like Schwalbe have a built in innertube, and don't even need sealant to set up.  I guess that makes them "tubeless easy".  LOL.
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bobknh

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Reply with quote  #17 
Quote:
Originally Posted by Slim
Yes, Compass has been adding tubeless version of their tire steadily in the last few years. given their super thin construction I would absolutely not mount a Compass tire tubeless if it was not explicitly rated for it. Regarding the original postings about rollling resistance: if anything, the super thin casing and rubber layer on Compass tires, will further help reduce rolling resistance at lower pressures. at high pressures, the rubber compound matters more, but as you drop presssure and deform the tire, suppleness starts to matter more. Keeping that in mind, I have always thought that Compas tires are probably some of the fastest tires for hilly gravel rides, due to their low weight and supple casing. On pavement, at higher pressures, others with better rubber compounds might be faster.

While I'm generally pleased with Compass tires, I do find their designation of their tires as "tubeless compatible" as opposed to other manufacturers designation of tires as "tubeless ready" a bit misleading. As others have suggested, the Compass designation "tubeless compatible" just means that their tire beads have been re-engineered to resist blow off when used with tubeless ready rims. It doesn't assure that their tires will hold air without a generous amount of sealant and lots of TLC to get them to seat. Tubeless ready tires like the Schwalbe G-One can actually be installed and run without any sealant. Of course, without sealant these tires lose their puncture resistance so I doubt anyone actually uses them without sealant to prevent punctures,
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Volsung

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Reply with quote  #18 

My Somas are made by Panaracer and are tubeless compatible, just like my old Snoqualmie Passes.  They hold air for weeks as opposed to a day or two with same rim.

 

EDIT- I think the problem is in the bead, not the thin sidewalls.

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bwepps

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Reply with quote  #19 
So.

I have the Compass Barlow Pass (700x38) tires and once I set them up tubeless I hated them.  Why you ask?  Some of these things have already been mentioned a bit by other posters:
  • Super supple sidewalls - too much so actually.  The tires once set up tubeless were very tall, BIG light bulb profile, and the thin sidewalls made them a bit "squirrelly."  Lots of side to side when you jam on the pedals at higher speeds.  (This is on 21mm internal width rims.)
  • "Tubeless ready" - the sidewalls didn't weep, but gushed Orange Seal when we set them up tubeless.  Good thing I was at my LBS, because we couldn't get them to seal without a compressor.
I enjoyed the feel of these tires better with tubes vs. tubeless.  But at the end of the day, I'm going back to some 700x38 Gravel King SK's.
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LewisQC

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Reply with quote  #20 
Quote:
Originally Posted by bwepps
  But at the end of the day, I'm going back to some 700x38 Gravel King SK's.


I should receive a pair of GK 38c this week. Reading report on tubeless problem with Compass, I'm glad of my choice...
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owly

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Reply with quote  #21 
Been using the extralight black Switch Back Hills for a few months now, setup tubeless.
Was careful with setup and sealant installation. Pretty much sealed up from the go.
Used OrangeSeal Endurance.

A few weeks later as the tyre stretched more, a handful of air holes appeared in the sidewalls (dunked the tyre/wheel in water to find them), though they sealed up with a sealant top up. 

Been running them on all kinds of gravel and singletrack.
Had a couple of thorn punctures which sealed right up. Other than that, nothing.

What I do remember coming across online when looking at these tyres was one forum comment saying the tan tyres were more prone to weeping than the black tyres, due to some difference in the sidewall makeup? Not sure if that is true though.

I think they're awesome. Have a set of extralight 42's now waiting for a new wheelbuild.






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