My 28mm Tyre Experience


  • 1. Taking a breather at the top of Norton Summit. It was hot and windy. 1. Taking a breather at the top of Norton Summit. It was hot and windy.
  • 2. The Giant Defy SL0 fitted with the 28mm tyres. The Defy has disc brakes so the 28mm tyres fit no worries. 2. The Giant Defy SL0 fitted with the 28mm tyres. The Defy has disc brakes so the 28mm tyres fit no worries.
  • 3. Close up of the 28mm tyres. 3. Close up of the 28mm tyres.


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Trying out 28mm Tyres


Given that I will be doing a number of 100 plus kilometre rides during January 2016 I decided to try 28mm tyres on my Giant Defy SL0. They easily fit given the Defy has disc brakes. Going for comfort for the "Ride Like Crazy" and the rides I will be doing around the TDU and the BUPA ride. Call me soft if you like but for me its all about comfort and enjoying the ride. Depending on how they feel I can always put the 25mm tyres back on when the endurance ride season is finished. I bought the Giant Defy as an endurance bike but it is proving to be a superb all rounder. Has to be one of the most comfortable yet stiffest bikes I have ridden and I can go real fast on it when I need too. Starting to wonder whether I still need my Giant TCR though I like the fact that the TCR has larger crankes and 11-23 rear cassette (perfect for the OH sprint) compared to the compact crankes and 11-28 rear cassette on the Defy.


To give the tyres a workout I took the Defy for a pedal up Norton Summit. First impression is that 28mm over 25mm is definitely way more comfortable. The bike feels more stable though the 25mm tyres were pretty good as well. Not sure whether there is more rolling resistance as it was very windy and I seemed to have a head wind all the way. I can say that I hit 70 kph at the very bottom of Norton Summit Rd on the way down which I have never done before. I felt very confident going round the bend to Magill Rd. Disc brakes help with the confidence. All in all 28mm tyres are going to give me a much more comfortable ride for the 100K+ rides though the jury is still out as to whether or not they will slow me down a little. I don't think they will or if they do it will only be minimal and well worth the trade off.


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Update 8 January 2016: Took the bike up Norton Summit again today and even with a strong head wind I found the tyres to be better than my 25mm tyres that I had on the bike previously. Both the 28mm and 25mm tyres are Continental Grand Prix 4000S II. I am now sure there is little to no difference in rolling resistance but most definitely there is both a massive difference to comfort and importantly stability. I feel so much more confident at speed on the 28mm tyres. I have been able to reach much faster downhill speeds on the 28mm tyres. I think this is because I just feel so much more stable and confident. I will post more updates on my experience over the next few days. Later in the the day I rode around McLaren Vale and even got a PB for Willunga Hill. After the Mclaren Vale ride a I am ceratin these tyres are worth it.


The Jury is back - 9 January 2016: Rode 146K from Adelaide to McLaren including up Willunga Hill again (Geez two days in a row up Willunga Hill - what was I thinking). I am now convinced it was a good idea to put the 28m tyres on. Apart from the comfort factor which is now even more apparent after a 146K ride I am also certain there is no additonal rolling resistance and if anything I think it might better. Today I managed some some big PBs on sections were I got up to nearly 60kph.


Update April 2016 - Verdict: I have now ridden the Ride Like Crazy, BUPA and Coast to Coast on my Giant Defy SL0 disc brake bike fitted with 28mm tyres. I am hooked. There is no going back for me on this bike I will be sticking with the 28mm Tyres. I had originally planed to revert back to the 25mm tyres after the long ride season but I won't be. I am convinced that the 28mm tyres are 1. Very very comfortable, 2. Very fast and 3. Much safer.


Not everyone will be able to fit them to their caliper brake bikes but if you can they are worth it especially for endurance rides. I have now also fitted them to my older Defy that has caliper brakes and the tyres fit on it as well.


Final verdict - HIGHLY RECOMMEND :-)