Pirelli P-Zero Race TLR RS - New All-Rounder King?

[208]

And when gp5kstr can be had for 90aud, the rs are a tough sell

Gambacicli sells them for 53 euro which is around 85 AUD, and their shipping is reasonable at least to the US.

Yeah went over that in a previous post. Still 30% more expensive in the best case once shipping is factored in for 2 tyres.

[cleanneon98]

Fair enough I can see why someone wouldn't want to take the gamble at that price. For me the Contis were $50 and RS were $60, yea it's a 20% difference but considering I go through one set a year $20 won't really break the bank. Upside is the Pirelli center tread is 15% thicker than the Continental so they SHOULD also last longer

[JaeTee]

Haven’t worked my way through the whole article, but some of the test data may be interesting to the conversation here (paywall):

https://www.cyclingnews.com/features/la ... e-fastest/


Scanning their conclusions…

The Vittoria Corsa Pro Speed tested fastest, saving 2.8 watts per pair over the Continental GP5000S TR. They considered the GP5000S TR the best all-around race tire. The slowest tire tested, the Pirelli P Zero Race 4 Season, loses up to 15 watts compared to the best option. They conclude the fastest tires (pair) can save ~30 watts at 40 km/h, and ~22 watts at 30 km/h when moving from slower four-season tires to race tires. Switching from butyl inner tubes to tubeless setups provides another ~8-watt gain at 30 km/h (haven't read their test methodology yet, but on this it appears like a doubling of a single tire test number which doesn't seem intuitive for front + rear).

Some single tire data...

GP5k S TR:
- Power at 9m/s: 10W
- Power at 11m/s: 16W

P0 RS:
- Power at 9m/s: 13.5W
- Power at 11m/s: 19.4W
- Vs GP5000 S TR at 9m/s: +3.6W
- Vs GP5000 S TR at 11m/s: +3.4W

For comparison, fastest in test was...

Vittoria Corsa Pro Speed:
- Power at 9m/s: 8.6W
- Power at 11m/s: 14.6W
- Vs GP5000 S TR at 9m/s: -1.3W
- Vs GP5000 S TR at 11m/s: -1.4W

[spartan]

did the test the grand prix 5000 tt. should be close the corsa pro speed

[TobinHatesYou]

Didn’t BikeRadar also go to the Silverstone facility and their tests showed the Pirelli P Zero Race (non-RS) faster than the GP5K S TR? Heh.

[JaeTee]

did the test the grand prix 5000 tt. should be close the corsa pro speed

Yes, you’re right, it’s second from the top in their test. Positioned between the S TR and the Corsa Pro Speed.

Continental GP5000 TT TR:
Power at 9m/s: 9.8W
Power at 11m/s: 15.9W
Vs GP5000 S TR at 9m/s: -0.2W
Vs GP5000 S TR at 11m/s: -0.1W

For reference in this test, they rank the Pirelli P0 Race RS 12th out of 24 tires tested at 30 km/h, and improved to 8th at 40 km/h. The top three I mentioned before retained their positions at both speeds.

Maybe this video is viewable outside the paywall (Hopefully ok to post, if not please let me know to take it down).

https://cdn.jwplayer.com/previews/miDvupgE

[TobinHatesYou]

did the test the grand prix 5000 tt. should be close the corsa pro speed

Yes, you’re right, it’s second from the top in their test. Positioned between the S TR and the Corsa Pro Speed.

Continental GP5000 TT TR:
Power at 9m/s: 9.8W
Power at 11m/s: 15.9W
Vs GP5000 S TR at 9m/s: -0.2W
Vs GP5000 S TR at 11m/s: -0.1W

These results are basically within margin of error and given the major differences in construction between the GP5K TT TR and S TR plus the previous test results from this facility, I have serious doubts about their protocol(s.)

[spartan]

looking at these numbers they do not correlate with vittoria own test protocol
.eg the used pirelli smart TPU tubes. these are the slowest tpu tested by bicyclerollingrestance

fun facts vittoria OWN test states vittoria TPU tubes are faster than latex.

"TPU tubes were slower, and butyl tubes slower still over tubeless. For our setup, we'd stand to gain 8 watts by swapping from butyl tubes to tubeless sealant using our benchmark tyre at 9m/s, which is about the same difference as that between our a tyre around the median of our range and the fastest pair."

We found that latex inner tubes were 0.4 watts faster at 9m/s and a watt slower at 11m/s than tubeless. Accounting for the margin for error for each test it's relatively safe to say that for our benchmark tyre, there was very little difference in performance between running latex tubes and running tubeless sealant.

[JaeTee]

did the test the grand prix 5000 tt. should be close the corsa pro speed

Yes, you’re right, it’s second from the top in their test. Positioned between the S TR and the Corsa Pro Speed.

Continental GP5000 TT TR:
Power at 9m/s: 9.8W
Power at 11m/s: 15.9W
Vs GP5000 S TR at 9m/s: -0.2W
Vs GP5000 S TR at 11m/s: -0.1W

These results are basically within margin of error and given the major differences in construction between the GP5K TT TR and S TR plus the previous test results from this facility, I have serious doubts about their protocol(s.)

Just edited my post above with a link to a half hour video that covers the test, if you can access, it probably will cover some of the protocol. To be fair, differences of a few watts in cycling are above my pay grade, but research methods I can weigh in on after I’ve had a look.

[BigBoyND]

These results are basically within margin of error and given the major differences in construction between the GP5K TT TR and S TR plus the previous test results from this facility, I have serious doubts about their protocol(s.)

Not to mention this part showing 35% more RR for the RS.

GP5k S TR:
- Power at 9m/s: 10W
- Power at 11m/s: 16W

P0 RS:
- Power at 9m/s: 13.5W
- Power at 11m/s: 19.4W

[TobinHatesYou]

These results are basically within margin of error and given the major differences in construction between the GP5K TT TR and S TR plus the previous test results from this facility, I have serious doubts about their protocol(s.)

Not to mention this part showing 35% more RR for the RS.

GP5k S TR:
- Power at 9m/s: 10W
- Power at 11m/s: 16W

P0 RS:
- Power at 9m/s: 13.5W
- Power at 11m/s: 19.4W

On its own, I'd have no reason to dispute those numbers, but here is the BikeRadar test showing the GP5K S TR around 14W@8.33m/s and the P Zero Race TLR at 11.9W. The absolute values won't translate across the two publication's tests, but the rank order should stay roughly the same.

[Kubackjeee]

So brr and aerocoach have Michelin power cup as one of the fastest tire and those guys have it as one of the slowest. Also on the graphics it's named "Michelin power cup" and on the first list it's "Michelin power cup tlr" - not that this should make a big difference or maybe it does in their testing method due to thread width? Don't really know how aerocoach and brr can get so much different results then those guys. But worth noting that this is their first test and brr/aerocoach are doing it for years.

[JaeTee]

These results are basically within margin of error and given the major differences in construction between the GP5K TT TR and S TR plus the previous test results from this facility, I have serious doubts about their protocol(s.)

Not to mention this part showing 35% more RR for the RS.

GP5k S TR:
- Power at 9m/s: 10W
- Power at 11m/s: 16W

P0 RS:
- Power at 9m/s: 13.5W
- Power at 11m/s: 19.4W

On its own, I'd have no reason to dispute those numbers, but here is the BikeRadar test showing the GP5K S TR around 14W@8.33m/s and the P Zero Race TLR at 11.9W. The absolute values won't translate across the two publication's tests, but the rank order should stay roughly the same.

I so haven’t read either one fully. But scanning quickly both tests were conducted about a year apart at the same lab - Silverstone Sports Engineering Hub. They don’t mention the engineering teams supporting the testing on either day, but one would hope an engineering facility has some standardization in testing protocols that could account for discrepancies between two differing methodologies they executed aiming to measure the same attributes.

[s]Even considering the confidence intervals, the contradicting results point at methods. BikeRadar showed the Corsa Pro as slowest (of . Cycling News show it as fastest (of 24).[/s](EDIT: as pointed out, I confused Corsa Pro vs Corsa Pro Speed. GoFundMe for my reading comprehension continued education here)

Bike Radar opted for the tire rolling resistance rig 30 km/h with 40kg vertical force. Cycling News opted for bike mounted rear wheel measuring the differential power between a rider pedaling on high res power meter pedals and the drum under the rear wheel.

Personally I’m more curious about what Silverstone has to say about two tests they performed with contradicting results than the actual tire efficiency results. Unlikely they’d comment about this kind of contract work, but I’ll update if they reply anything interesting.

From the BikeRadar test:

Code: Select all

 Our lab testing was performed at the Silverstone Sports Engineering Hub, on its bicycle-specific rolling resistance rig.

This rig uses an oversized, motor-driven roller to rotate a wheel, with a vertical mass applied to simulate a rider’s weight deforming the tyre as on the road.

Using a torque meter, the machine can then determine the rolling resistance of a tyre by comparing the power required to turn the roller at a given speed, with and without the tyre contacting it.

All else being equal, tyres that produce less rolling resistance should enable you to ride at a given speed for less effort.

From the Cycling News test:

Code: Select all

 The fundamentals of the test are extremely simple. A bike is mounted with its rear wheel atop a rotating drum. Body Rocket power meter pedals measure the power going into the bike at 100hz, substantially greater than standard pedal-based power meters, and sensors on the drum measure the power actually reaching the 'road'. Any discrepancy between these two numbers is the total power loss through the bike.

This setup differs from a dedicated tyre rolling resistance rig in that the energy loss it shows will also include energy lost in the drivetrain and any flexing of the frame and wheel.

However, as those losses remained constant throughout - the only variable we changed was the tyre - the differences between each test result are down to the rolling resistance performance of the tyres. 

Silverstone Sports Engineering Hub does have a tyre rolling resistance rig, but in much the same way as in our wind tunnel tests, we wanted to make things as applicable to the real world as possible. The rolling resistance rig uses a metal drum, while the drivetrain efficiency rig uses a much larger drum with a simulated tarmac surface taken from a scan of a Paris street, creating a much more realistic contact patch. The pedalling efficiency rig also uses a real rider - in this case our Associate Editor, Josh - and therefore the small oscillations and vibration absorption that come with using a human to power the bike.

[bobones]

Even considering the confidence intervals, the contradicting results point at methods. BikeRadar showed the Corsa Pro as slowest (of . Cycling News show it as fastest (of 24).

Corsa Pro Speed is a not the same tyre as the Corsa Pro.

[JaeTee]

Even considering the confidence intervals, the contradicting results point at methods. BikeRadar showed the Corsa Pro as slowest (of . Cycling News show it as fastest (of 24).

Corsa Pro Speed is a not the same tyre as the Corsa Pro.

This is why Huberman says we shouldn’t be on our phones in bed at midnight. Jk one day I hope to learn to read.