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Track Tire Questions

Old 08-16-17, 03:59 PM
  #251  
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Originally Posted by sarals
By the way, I misspoke. The 25MM tires on my training wheels are Tufos. They've been just fine! They're great at Hellyer, and they've been a non-issue at VSC.
Sarals,could you share which model of Tufo's you're using? I'm thinking of getting some for my training wheels, but I've been wondering if they'd work on wood, thanks.
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Old 08-16-17, 05:40 PM
  #252  
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Originally Posted by Baby Puke
Sarals,could you share which model of Tufo's you're using? I'm thinking of getting some for my training wheels, but I've been wondering if they'd work on wood, thanks.
I currently use a Tufo S3 Pro with a width of 21mm. I worry about the small amount of thread wrap-around. I use it on a 41.5 degree wood track with no problem. However another rider slid of the track using the same tire.
I plan to switch to Conti Sprinters next year.
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Old 08-16-17, 06:12 PM
  #253  
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Originally Posted by Baby Puke
Sarals,could you share which model of Tufo's you're using? I'm thinking of getting some for my training wheels, but I've been wondering if they'd work on wood, thanks.
@Baby Puke, believe it or not, they're S33's. They're reputed to be hard and slippery, but have worked very well for me on the boards, and they are excellent at Hellyer, on the concrete. Maybe it's their width, I don't know, but they've been just fine. I'll throw a thought out there, I'm not a guy and therefore not all that powerful, and I don't weigh all that much, either. Does that have a bearing? Maybe.
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Old 08-16-17, 08:04 PM
  #254  
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I've ridden many Tufo tires back in the day, as well as the oft referenced Sprinters, along with many other tires. I know that the Sprinters have changed over the years, but Tufo's line-up has been very stable for a long time. It may be that I had better access to the Tufos compared to other riders ( I would call up the factory in the Czech Republic and order tires direct from them. Languages ). I even gt a few of their World Cup only tires thrown in with a couple of my shipments.

In my experience, Tufo's were no worse/better than the mainstream high end tires you could get through your LBS or North American mail-order. I never found them slippery, and I rode them regularly on the only plastic coated tracks in NA. They are fast, and many people also think they seem "harder". This I can attribute to most people pumping them up higher than their regular tires. People see the 220 PSI that you can pump them up to, and figure "why not?". This is fine for a pursuit on a smooth, compliant track. In reality, I used to run them between 130-150 psi.

They had better grip than Conti's silica tread compounds in my opinion. The black carbon compounds were about equal between the two brands. Many people also decry their low thread counts in the casing, but if you go for the Elite model, then the tire specs are abut equal to other high end tires, at little more than half the price. Their World Cup only tires that I tried were the best tires I had ever used. These had a painted on latex tread similar to Dugast or FMB tires. I haven't ridden those tires, so I can't compare them, but the Tufo tires weighed in at 85-90 grams.
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Old 08-16-17, 09:24 PM
  #255  
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Originally Posted by Divebrian
I put a set of new Pista EVO CS's on my race wheels. ... I'm going to Worlds in a couple of months in LA and would like to know if these tires are suitable for the track there? ... They have a fine diamond pattern on the tread and I know the EVO's come in a slick tread with no diamond pattern as well.
I used the Evo Pistas as my primary racing tire there for several years of doing basically every race there (primarily mass start, including Madison) and they're great tires. They handle well and stick well. I'm not convinced the tread vs slick makes any difference- tread does very little for road or track tires in any case. See my post in the early days of this thread for opinions on a bunch of tires. I was on that track 2-3 days/week (sometimes more) for about 6 years. I'd link it but I'm limited to my phone right now on a bike trip.
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Old 08-17-17, 05:44 AM
  #256  
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Originally Posted by taras0000
I've ridden many Tufo tires back in the day, as well as the oft referenced Sprinters, along with many other tires. I know that the Sprinters have changed over the years, but Tufo's line-up has been very stable for a long time. It may be that I had better access to the Tufos compared to other riders ( I would call up the factory in the Czech Republic and order tires direct from them. Languages ). I even gt a few of their World Cup only tires thrown in with a couple of my shipments.

In my experience, Tufo's were no worse/better than the mainstream high end tires you could get through your LBS or North American mail-order. I never found them slippery, and I rode them regularly on the only plastic coated tracks in NA. They are fast, and many people also think they seem "harder". This I can attribute to most people pumping them up higher than their regular tires. People see the 220 PSI that you can pump them up to, and figure "why not?". This is fine for a pursuit on a smooth, compliant track. In reality, I used to run them between 130-150 psi.

They had better grip than Conti's silica tread compounds in my opinion. The black carbon compounds were about equal between the two brands. Many people also decry their low thread counts in the casing, but if you go for the Elite model, then the tire specs are abut equal to other high end tires, at little more than half the price. Their World Cup only tires that I tried were the best tires I had ever used. These had a painted on latex tread similar to Dugast or FMB tires. I haven't ridden those tires, so I can't compare them, but the Tufo tires weighed in at 85-90 grams.
Taras, did you also ride the S33's that Sarals is on? Those are the ones I'm interested as they come in 24mm and are dirt cheap. These would be for my training wheels which have Araya Golds, and those rims don't work well with narrow tires, which would pretty much rule out all the other Tufos. Thanks
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Old 08-17-17, 08:15 AM
  #257  
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Yeah, I'm curious about the S33s as well.

I have a Tufo S3 Lite 21mm (tubular-clincher) on one of my front wheels. Out of the package, it's very sticky...which may be good or bad. Good that it's sticky to the touch. Bad in that it may simply grab a layer of dust and hold on to it.

I've only used it outdoors on concrete. I'm curious to know if it would be appropriate for use at ADT/LA/Home Depot/whatever it's called.
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Old 08-17-17, 04:45 PM
  #258  
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Originally Posted by Baby Puke
Taras, did you also ride the S33's that Sarals is on? Those are the ones I'm interested as they come in 24mm and are dirt cheap. These would be for my training wheels which have Araya Golds, and those rims don't work well with narrow tires, which would pretty much rule out all the other Tufos. Thanks

Yup! They were how I first got into trying out Tufo. I also used them as my training wheel tires. Never had any problems with them. Would still buy them today if I needed tubs.
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Old 08-17-17, 09:25 PM
  #259  
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Great, thanks Taras! My next tire purchase then. I love cheap stuff!
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Old 08-17-17, 10:24 PM
  #260  
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Originally Posted by carleton
Yeah, I'm curious about the S33s as well.

I have a Tufo S3 Lite 21mm (tubular-clincher) on one of my front wheels. Out of the package, it's very sticky...which may be good or bad. Good that it's sticky to the touch. Bad in that it may simply grab a layer of dust and hold on to it.

I've only used it outdoors on concrete. I'm curious to know if it would be appropriate for use at ADT/LA/Home Depot/whatever it's called.
I would use them. Like I said above, They weren't any worse than other high end tires. Rochester Hills and Bromont were slippery compared to most tracks (that protective plastic layer on the wood), and I found no problems on those tracks. The tires are sticky out of the box, but I found that to be because they came from the factory extremely clean. Most tires still have that layer of mold release on them when they are new. I found the Tufo tires didn't have this on them. I still gave them a good clean with rubbing alcohol and a few swipes around the tire with a scotch-brite pad. The tread compound is quite soft on the Elite models. It doesn't wear too quickly, but it is definitely a race tire in my opinion. They also keep the weight down with a thinner tread, so anyone looking to make a purchase may want to bear this in mind.

All in all, they are probably the best value in tires on the market, and I would't hesitate to purchase them again. I would recommend them to anyone looking to try something new, as they definitely won't hold you back.
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Old 08-17-17, 11:36 PM
  #261  
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Thanks!
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Old 08-18-17, 01:24 PM
  #262  
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Just to add to my (albeit limited) experience with my S33's - I run them no higher than sidewall pressure, which is 115. On Hellyer I ride them at 110, at VSC 115. The Sprinters I run at 140 -160 at VSC, 130 at Hellyer. The S33's show little if any wear since I started riding them at Hellyer in November, and I've done 45 training sessions, plus warmups in four mass start omniums on them. Zero complaints from me!
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Old 09-01-17, 05:02 AM
  #263  
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So I just mounted up a set of these Tufo S33 Pro 24's. Some observations:

They are really wide, I measure them at just a hair over 25mm. I might opt for the 21mm's next time. They were also really tight to mount, on par with Conti Steher's which are the tightest tires I've encountered, but they loosened up enough after stretching that gluing them on was not a worry. They indeed are very round and look to be much nicer tires than similarly priced offerings from Conti And Vittoria (Giro and Ralleye).

They are REALLY slow on rollers. I mean really, really slow. Maybe on par or worse than garden-variety clinchers. They are slow to the point that I have to change my workouts as I just can't finish the efforts I was doing before, and my old training tires were Sprinter Gatorskins, which are not exactly reputed to be fast. I basically cannot do recovery rides on the rollers with them, they have too much rolling resistance. I'll be riding them on the track Sunday, so I'll report back on that, but I'm a bit scared. I mean, these are training tires, but I was hoping for a bit more performance.

I'm wondering if part of the problem is the max pressure. These are rated at max 8 bar/115 psi, which seems really really low to me. Anybody have knowledge of what kind of pressures they can really take? They certainly seem robust enough to take more, maybe 150?
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Old 09-01-17, 02:26 PM
  #264  
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Give them a bit and see if they speed up. I never had a problem like this with any of my Tufos. I also didn't run them that low a pressure as all of mine were rated for 210psi.
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Old 09-01-17, 02:29 PM
  #265  
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I would try a higher pressure as well. I was just looking at their website and the 21mm version is rated 115-175 psi. Don't know why the 24 is only 90-115. In the past they were higher. Maybe they "recommend" that max because they think it will ride too hard above that.
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Old 09-01-17, 05:00 PM
  #266  
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Excellent, thanks Taras. I'll try them at 150 and report back. What did you run them at, and did you use the 24's or the 21's?
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Old 09-01-17, 06:25 PM
  #267  
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I had S33 24 on my road bike. I think they were the first Tufo tires that I had ever picked up, and I think I ran them about 125 psi. I've used the S3 tires on the track, as well as the Elite S3 23, the Elite Jet, but the Elite 135 is what I usually rode. I typically rode those with 130-150 psi.
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Old 09-01-17, 09:28 PM
  #268  
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Originally Posted by Baby Puke
They are REALLY slow on rollers. I mean really, really slow. Maybe on par or worse than garden-variety clinchers. They are slow to the point that I have to change my workouts as I just can't finish the efforts I was doing before, and my old training tires were Sprinter Gatorskins, which are not exactly reputed to be fast. I basically cannot do recovery rides on the rollers with them, they have too much rolling resistance. I'll be riding them on the track Sunday, so I'll report back on that, but I'm a bit scared. I mean, these are training tires, but I was hoping for a bit more performance.
Some people think Tufo's are fast because high pressure, but there's a lot more that factors into rolling resistance than tire pressure. Whenever they're tested, Tufos tend to be bottom of the pack in rolling performance, with literally twice the rolling resistance of the best tires. Google "tufo rolling resistance" and you can find plenty of discussions and test results. For instance

Why do people hate TUFO tubulars? - Weight Weenies

The definitive rolling resistance thread.....

I'll be riding them on the track Sunday, so I'll report back on that, but I'm a bit scared. I mean, these are training tires, but I was hoping for a bit more performance.
I'll be surprised if you get better results on the track with them, since rollers are pretty much the best case scenario. Even the best indoor tracks aren't going to be as smooth as a roller, and as the surface becomes less smooth, the penalty for a given increase in Crr is magnified.


I'm wondering if part of the problem is the max pressure. These are rated at max 8 bar/115 psi, which seems really really low to me. Anybody have knowledge of what kind of pressures they can really take? They certainly seem robust enough to take more, maybe 150?
Raising the pressure will help to a certain extent, although probably nowhere near enough to make up for having twice the Crr as other tires. And if you go too high (exactly how high depends on the road/track surface), things will actually get worse. BTW that entire 5-part series by Silca is a worthwhile read if you want to learn about all the factors that go into rolling resistance. Some of their conclusions are surprising in that they directly contradict conventional wisdom, but they did a pretty good job of showing the science behind the conclusions as well as test results that validate them.

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Old 09-02-17, 12:01 AM
  #269  
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Originally Posted by jsk
I'll be surprised if you get better results on the track with them, since rollers are pretty much the best case scenario. Even the best indoor tracks aren't going to be as smooth as a roller, and as the surface becomes less smooth, the penalty for a given increase in Crr is magnified.
Rollers deform the tires much more than the road does, so tire pressure (or lack thereof) is accentuated. That deformation is where the friction comes from. Further, the tires are deformed in 3 places on rollers, not just 2 like when on the road/track.

+/-20PSI on rollers can make a night and day difference in how the rollers feel.

Originally Posted by jsk
Raising the pressure will help to a certain extent, although probably nowhere near enough to make up for having twice the Crr as other tires. And if you go too high (exactly how high depends on the road/track surface), things will actually get worse. BTW that entire 5-part series by Silca is a worthwhile read if you want to learn about all the factors that go into rolling resistance. Some of their conclusions are surprising in that they directly contradict conventional wisdom, but they did a pretty good job of showing the science behind the conclusions as well as test results that validate them.
Yeah, but all of these studies are of road riding conditions where they ride on the middle of the tire and put no G forces into it in the turns. Further, there aren't nearly as many deformities on a track (even "bad" tracks) that are on the road. So, it's not really comparing apples to oranges.

If lower tire pressures were the big boost that these blog posts would have you believe, you know trackies would be all over it. I mean, this has to be the cheapest equipment A/B test that's possible. It's not like people are taking 0.5" off of their flying 200s when they drop 30PSI.

Maybe just ride a 1KM pursuit at race pace at 140psi and maintain the same speed and let the SRM log the power needed to do so, then come off and rest and lower to 110PSI and repeat. Do that several times over a few days, maybe even have your buddy set the pressure and don't tell you, and you will have a proper experiment. The data will show if this applies to track or not.

I'd accept that in a track context over the hundreds of blog posts that tell people that they should be riding wider tires at lower pressures...on all bikes on all terrain.

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Old 09-02-17, 12:18 AM
  #270  
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Also:

Why don't these charts start the Y axis at 0? They are accentuating the deflection:



Why is the spacing of the Y axis not uniform??

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Old 09-02-17, 01:49 AM
  #271  
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Yeah, I find rollers are kind of a magnifying glass for how tires feel. These Tufo's feel really slow, but when I put on my race wheels with Vittoria Pista EVO's they are so fast I can barely ride them. But this is not how different they really are on a track (though they will be significantly different). By the way, my rollers are 3" Minoura's, so quite a bit more resistance than the big Krietlers, for example.

And I'm with Carleton on the pressure thing. Maybe in a road situation low pressure is better, but I'll keep pumping my race tires so 200 psi, thank you very much.
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Old 09-02-17, 10:05 AM
  #272  
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Originally Posted by carleton
Rollers deform the tires much more than the road does, so tire pressure (or lack thereof) is accentuated. That deformation is where the friction comes from. Further, the tires are deformed in 3 places on rollers, not just 2 like when on the road/track.

+/-20PSI on rollers can make a night and day difference in how the rollers feel.
Fair enough. Glancing at the chart that shows Crr for both rollers and different road surfaces, I saw that Crr was lower on the rollers; but I forgot to account for the fact that they're recalculating the road Crr to account for the factors you mention.


Yeah, but all of these studies are of road riding conditions where they ride on the middle of the tire and put no G forces into it in the turns. Further, there aren't nearly as many deformities on a track (even "bad" tracks) that are on the road. So, it's not really comparing apples to oranges.
Setting aside your apparent assumption that roadies only ride in a straight line , aren't most outdoor tracks concrete? How dissimilar do you think the friction on smooth concrete is compared to the smooth asphalt Silca used for one of their test scenarios? In my experience, asphalt is faster than concrete. And while I can't speak for other tracks, at Alkek there are enough surface irregularities that I would say the surface is no better than most of the roads I ride on, and actually worse than quite a few of them.

If lower tire pressures were the big boost that these blog posts would have you believe, you know trackies would be all over it. I mean, this has to be the cheapest equipment A/B test that's possible. It's not like people are taking 0.5" off of their flying 200s when they drop 30PSI.
First, the tire pressures they talk about in that article for smooth surfaces are not all that low. Second, I didn't reference the articles to advocate a specific tire pressure. I just wanted to mention that raising tire pressure up to a certain point will improve Crr, but raising it past that point will actually make it worse.

Getting hung up on track vs road tire pressures completely misses my point though. My main point was that whatever pressure you decide to run, the Tufo's will be a poor choice with regard to rolling resistance. No amount of tire pressure is going to make up for the fact that the casing and tread compound on those tires are ****. There are better choices both for training and racing tires.


Maybe just ride a 1KM pursuit at race pace at 140psi and maintain the same speed and let the SRM log the power needed to do so, then come off and rest and lower to 110PSI and repeat. Do that several times over a few days, maybe even have your buddy set the pressure and don't tell you, and you will have a proper experiment. The data will show if this applies to track or not.

I'd accept that in a track context over the hundreds of blog posts that tell people that they should be riding wider tires at lower pressures...on all bikes on all terrain.
I actually plan to do some testing of this sort during the off-season. My main focus will be aerodynamics for pursuit, but testing different tire widths/pressures would also be interesting. Unfortunately Alkek is currently under 7 feet of water, so it isn't going to happen anytime soon.
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Old 09-02-17, 10:11 AM
  #273  
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Originally Posted by carleton
Also:

Why don't these charts start the Y axis at 0? They are accentuating the deflection:
Crr will never approach 0, it would just add extra white space below the line. The curve is already getting pretty flat on the right side, showing diminishing returns as pressure goes higher.

Why is the spacing of the Y axis not uniform??
That's common when charting non-linear data, it makes small differences more distinguishable at the flat end of the curve.
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Old 09-02-17, 10:24 AM
  #274  
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Originally Posted by Baby Puke
And I'm with Carleton on the pressure thing. Maybe in a road situation low pressure is better, but I'll keep pumping my race tires so 200 psi, thank you very much.
Feel free to run whatever pressure you want. I would never run anywhere near that psi on my outdoor track, but I have no idea what the optimal pressure is on a smooth indoor track. Whatever pressure you run, the Tufos are going to be slower than other options, though.
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Old 09-02-17, 12:29 PM
  #275  
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Originally Posted by jsk
Crr will never approach 0, it would just add extra white space below the line. The curve is already getting pretty flat on the right side, showing diminishing returns as pressure goes higher.


That's common when charting non-linear data, it makes small differences more distinguishable at the flat end of the curve.
This is common...and very bad form in term of charting data. One should always show the starting point of an axis to show relative scale. Data Science/ Analytics is a big part of my work.

The scale should be uniform linear or logarithmic. Not arbitrary.

Whoever made that chart did that for dramatic effect, nothing more.
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