thanks for trying its much appreciated, well I have ordered the tires so hopefully they are OK
The GP 5000 tires are true to size, so the 700 x 25 that you ordered will likely measure 25.5-26mm. That will be perfect if your rimās outside width is 26-28mm.
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I use Vittoria latex tubes. Silca also make a latex tube thatās goodā¦but rarely in stock (working capital problems?).
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What tire would be a good compromise between the Gatorskins and GP 4000? I like not having flats, but if I could go a bit faster, that would be nice as well. My Prime rr-38 are tubeless ready.
The GP 4000s are honestly a decently sturdy tire. If you ride in areas where they flat often then the best move would be to go to a tubeless tire.
That is why I switched from GP 4000S II and went tubeless.
A good comparison between tires and brands can be found at bicyclerollingresistance.com. Look in the right hand column.
Gatorskins - 19.3 watts
Grand Prix 4000S II - 12.2 watts
Grand Prix 5000 - 10.0 watts
Grand Prix 5000 TL 8.3 watts (Tubeless)
The values are per tire.
Hi, good discussion but you might want to consider that rolling resistance is related to speed and importantly road conditions and weight (or the rider and bike). I donāt know about other calculators but I know if you enter āgatorā into the FFT tyre calculator (bit.ly/ffttyre) and then repeat with ā5000ā you can directly compare the losses in aero and CRR for your weight and road surface. I think there is a Japanese calculator too, but I cannot get it to work atm.
Out of curiosity, did you ride the 4000s with latex or butyl tubes? Iām making the switch to latex this year and had read that they improve the ride quality by absorbing some of the vibration.
Butyl tubes, about a 1.9 watt penalty over latex:
I went from Conti 4000S II to Schwalbe Pro One tubeless. After a sidewall tear I had to put a tube in the Pro One rear tire. Ride quality didnāt seem to change much after putting in the tube. Would really need to do a head-to-head comparison to say for sure about ride quality and grip. My favorite so far was the S-Works Turbo, although I couldnāt get it in 26mm a few weeks ago so picked up the 5000 TL. Still havenāt had a chance to ride outside on the 5000 TL.
Maybe someone more knowledgeable than me will chime in, but the testing conditions there donāt seem realistic.
Speed: 29 kmh / 18 mph, Load: 42.5 kg
I just do tri so my avg speed will be higher and Iām definitely not 43kg - right about 67kg. Iām curious how this would affect those results? Will a heavier rider yield more or less benefit? What changes when your speed is closer to 22mph vs 18?
Just saw the post about the 4000s inflating wideā¦ my order just came in. Need to double check now. I have clenchers and donāt think the wife would be all too enthused by me buying new wheels haha looking at all these cheap watt gains first and continuing to build my engine/work on lowering my CdA!
That is load on a single tire.
So, if you assume a 50/50 weight distribution, that is 86 kg load (43 kg x 2) for a rider and bike estimated weight.
In most cases, the weight is higher on the rear tire. Something more like 60% rear, 40% front is likely. But the load in the test is quite realistic, IMHO.
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Oh right. Thanks for clearing that up!
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I just ordered a pair of Silcas from biketiresdirect. But theyāre just Vittorias anyway, arenāt trey?
Just another tip, if youāre running latex tubes in your wheels, consider bringing a butyl spare (if you carry spare tubes). The reasoning is that a roadside repair is naturally going to be a bit more hurried and rushed than doing the swap at home. Speaking from experience, latex tubes are not accommodating to even the slightest of misalignment.
Do you use any special rim tape?
Guys, how do you find GP5000 in 25 width, are they closer to GP4000 23 or 25 feel and performance wise?
They say GP5000 are more true to their advertised size, unlike 4000, which are 2mm wider than stated?
Many thanks
New tyres are going on tonight with new tubes in anticipation of a race on sunday, how long do you think I should be riding to make sure they arenāt defective, I keep thinking of Jonathanās race day where he shredded multiple tubes and had to walk 8 miles.
Are they? I thought the attachment of the valve stem to the tube was different on the Silcaā¦but Iām no expert. Vittoriaās are fine. But vittoria doesnāt have a blog and podcast full of fun facts. So, for the same priceā¦
Iāve just been using Stanās, but I havenāt experimented at all with that.