I stock up on 23mm Vittorias when they go on sale "over there". I also bought Bontrager tubulars (24mm?), whatever their handmade one is called, but that was mainly to support the LBS that sponsors the team.

I've bought contis (sprinter and something else, I think the Grand Prix) but the handmade ones are all impossible to mount straight. There's something to be said for half-man-made tires, they have straight casings. I dismounted perfectly good Contis because of that. On the road it's hard to tell, but you get on rollers and the bike is thudding like you're riding on cobbled rollers. On Vittorias/Bontragers no noise/etc. Same wheels, same gluer (me).

I am under the impression that Michelin makes tires in that same Thailand factory as Vittoria/Spec/Bonttrager/everyone-else-in-the-world but that they have their own rubber; I think they brought their machines over to the factory, and no one else can use them. The other tires are all a la carte for the rubber. I'd be curious to try out their tubulars but honestly I cut the clinchers pretty quickly (Pro3?) and I have so many new/extra tires (10?15?) that I really need to use them up first.

I haven't tried 25+ mm tires but due to clearance they're probably not possible or more susceptible to problems.

i know those roads and races.

you are RACING, right? this is a RACE bike?

your first line talks about training. i do advocate the 50/34 for training--that can be helpful. still think you can get by for just about every race scenario with the 53/39, and sometimes you will really want it.



i know that TT--have a few athletes i work with who have raced it. 55/42 is still great. 4% isn't really much of a climb, esp for a 20' effort.

you're going to have a worse chainline in many cases. more drag. (friction)

in my own testing and all the testing i've read, michelins haven't come out on top.

best thing to do, though, is one's own Crr testing. it's pretty easy with a set of rollers and answers lots of questions.

FWIW, they got here and I've ridden them twice. The first ride was yesterday, just an easy recovery ride on smooth pavement. Today was 43 miles on the local group ride and then another 57 solo. The group ride stayed on mostly good pavement but did cross railroad tracks a couple of times. The usual "thud" was noticeably muted. When I went out solo, I made a point of riding on some fairly gnarly pavement and the ride was much better. I hit some rough chipseal that always bugged me and it was much more tolerable; it almost felt like tarmac. Cornering wasn't noticeably better, but I was riding decent tires before (Specialized Turbo Pro) and I wasn't pushing it in the corners.

Some additional notes:

Mine are 700x28s, and they do have "Hell of the North" on the sidewall. They have a cross-hatched tread in the center of the tire, where the smaller versions have smooth tread. The front measures 27.3mm at 80 psi, and the rear is 27.6mm at 90 psi. This is on Boyd carbon rims that measure 23mm on the outside.

I'm currently running standard butyl tubes in them because the valve extenders I needed for the Vittoria latex tubes I have weren't in when the tires got there. The extenders came in and I'll probably swap tubes Monday.

Tread wear is going to be a determining factor in whether I settle on these as a permanent choice. I really like them so far, but I'm hoping I can get at least 1500 miles from a rear tire. Time will tell.

Skinwalls look *****in' on my chameleon purple Allez Sprint. :)

Everything looks awesome on that paint job!

Hopefully this is legit, I'll definitely consider buying SRM pedals, so long as they're not massively overpriced.

Attachment 604569

Since the link fell off. here's a snip of the tweet. And I'd consider the same.

Great point.
A same mfg/case/model 25mm@105 is pretty close to a 23@125 on rollers or a smooth road.
However I see charts testing both at the same PSI.

The test should be at the PSI you plan to ride each tire.

Air Force kids have got piles of the Michelin tires and tubes. Somehow it is associated with other contracts. I really like the rubber (not talking about the case, and whole tire). The inner tubes are noticeably more supple and I think the tread is gummier than the Vittoria/Bontrager/Conti stuff. The Specalized Turbos have the similar feel durometer.

Crr come from much more than rubber, but I noticed that.

agreed.

it bothers me when people test 23, 25, 28 at the same pressure.

then again, most (all?) tires exhibit different Crr at different pressures -- and the changes are not linear not consistent across all brands.

generally speaking, though, trends emerge and it is possible to have pretty high confidence in extrapolating high-quality data. wind tunnel data on wheels is a good example of reliable data to extrapolate; aero data on frames is too personal (impacted too much by rider position) to be of a ton of use, in most cases.

if doing one's own testing and multiple tire widths are coming into play, i suggest using some kind of consistent standard like how tall the inflated tire is (sagged, with full rider weight) and use whatever pressure is required to get there.

for most folks, published data is good enough. i just want people to know that testing for oneself is not that hard.

years ago, for a particular hillclimb i did an experiment to figure out if tire pressure mattered on a given stretch of road. i was pretty shocked at what it revealed in terms of optimal PSI (for me, for that road). it was also pretty easy to do in the field during a regular interval session -- just meant i got some additional data from it without impacting training. definitely not a lab scenario.

While wind tunnel data on wheels I expect is pretty repeatable, it is different than riding. I saw some wheels took higher HR to manage at the same power. The question became was it worth it for the speed.

Choosing between a 50mm or 80mm rim or a Veloflex Record 22 vs a Vittoria Corsa Speed G+ 23 (actually thinner than the 22), is hard. It is harder when a glue job is needed to test. Sometimes I just squeeze them @ 30 PSI and guess.

I've seen a lot better seating/straighter tires than the FMB silks. I have not seen anything in the 25mm that rolls better, or is even close. At the time Francois was making the standard stuff for Sky, he was happy to build weird combos for me. I had some made with no sidewall coating and the record tread on. I don't really need to test those.

tunnel data doesn't answer every question. i'm assuming you've been in tunnels before so you already know this, but i tend to find each 'answered' question raises more questions.

that said, wheel data is very reliable for answers to SOME comparative questions.

it assumes that (a) riders know what effective yaw they will ACTUALLY experience and (b) that other differences (e.g., stall points, which i find affects handling, although it is not the only thing that affects handling) are equal.

the actual choice for what to ride is not just about what tests fastest in the tunnel; however, that is certainly one important input.

lack of good Crr data on tubulars is one reason i first did my own testing. i found that published testing on tubulars (a) often featured glue jobs unlike those i would race in "important" events and (b) did not reflect the tires i might ride (eg conti's with latex, as one example).

tubulars usually hold true to their width from rim to rim to rim due to the nature of the construction. clinchers, as you likely know, adapt to their rim, and as such the tire-rim combo is important for both Crr and aero testing.

another reason why one really doesn't know unless they test their own combo, and sometimes choosing "the best" tire + "the best" rim = worse than what is a sub-optimal combo on paper.

"i have not seen anything that rolls better" == how are you measuring this?

PE :-) No measure. Just not needed IMO. All soft stuff, I know it is soft stuff. They are so slippery on rollers junior won't use them to warm up as he can't get his power / resistance on them.

But when comparing to a fairly low Crr Veloflex (our goto tire for the combo of price, Crr, weight, flat resistance for where we live) you can see a difference @ :09 same two tires, same PSI the FMB flexes around the Veloflex. I don't have these videos of the raw silk sides, but they *in theory* being sidewall coating free even lower Crr.

2nd half of this video ignore - but was me wondering if the roll of the tire could be picked up in the camera. The Red Veloflex was a clincher. Then the FMB and a Duguast Cotton PR tire (after being used in PR). All were very tightly glued, I didn't see anything there.

The 15-16s were talking about yaw of the VOS cross winds. I told them if they just went 30 or so the yaw would always be within the ideal angle for the rims.

I got weird stares (I am used to that).

Many kids don't understand the yaw is the resultant vector of the wind and the velocity of the bike vectors.

Wind tunnels have the bike at an angle for yaw.
Are there any tunnels that turn the bike into (reduce yaw) as power goes up? I don't know if it is needed, but that is closer to the real effect of speed and yaw.

that's just like 3 minutes of tires sexing

lolol

Recently my bb/cranks/I don't even know started creaking when going over 350w, so I wanted to reinstall it..

So I was hammering away on my BB cups tonight, trying to get them out. No luck.

This endeavor opened up a can of worms; now I realize the previous install (done by a shop) was strange; the wavy washer was on the drive-side, but normally it goes on the left side. And also I realized the cups I'm using are technically not the right ones - they're for "Power Torque" but my cranks are Ultra Torque.. how did this ever work??

When I tried to put the cranks back on, there was too much friction (w/ the wavy washer on the left or ride side).

Hopefully the (new) shop can figure this out, I'm lost. I just want to race the damn thing!

I've been dealing with a creaky/ticky bottom bracket as well. Using GXP on a BB30 Tarmac. Tried wheels mfg outboard BB and a Praxis Conversion BB. Both click. Last ditch effort was made last night buying a new wheels mfg and installing it with loctite to keep things tight.

I just got a Tacx Neo. Its either for me or the wife but sharing a smart trainer wasn't working. Its pretty cool so far, feeling the cobbles etc.

The one thing that vexes me is power. It feels low, or more accurately, different than my Elite Direto. The Elite's spin action in rougher and I'm actually used to that. The Tacx is smoother and spins longer. I won't really know how it is until I put a real 20 minute effort on the thing. With 4 different power devices, I'd like to run some tests and see where everything measures.

I had a similar issue recently. My Praxis conversion BB was squeaking/creaking. I removed and re-installed it twice, no dice. Ordered a new BB. While waiting for the BB to get here, I swapped out the new Look Kéo Max pedals and the noise went away. :rolleyes: Now I'm waiting for the warranty replacement pedals.

My Tacx Flux (both of the ones I've had) runs low. The first one was a consistent 10% across the board, cold and warmed up. The second one starts around 10% and then gets to around 4-5% at higher power and is closer to 10% at lower power.

But I just use my powermeter to control things and it's all good.

Just got some 38mm Zipp SL70 Aeros. Oh, yes. This was what I've been waiting for. I like these bars a LOT!

And it only took about 2 minutes to get the cable routing through (Shimano mechanical). Of course, it took another 1.5 hours to recable the entire bike and swap out everything...

Better get those few extra watts...

every time I think it's the BB/pedal/spider/chainrings creaking it's always been the skewers and or hub bearings coming loose.

I am moving to internal-cam skewers on all my bikes now.

I have the Neo as well. I see around 15W difference (Neo is lower) when compared to a P2M NGeco and a Quarq Riken R. I use power match on Zwift and just set Sufferfest to 90%.

My theory is the lack of a weighted flywheel in the Neo means the magnets are applying resistance constantly, which means its a full circle effort to keep the same power.

I hate creaky noises on a bike. It drives me nuts.