Undoubtedly this is down to two things:
- Continental GP4000 tyres - cool website ...
- Sludge tyre sealant - hmmmm ...
Firstly, the Contis.
These are very nice tyres indeed. Handmade in Germany and an obscene price here in the States, fortunately they're available from the UK at a much more sensible price, which my LBS tells me he can't even match here in the US at wholesale.
The first big plus is that tyres can be pumped up to 120psi, but despite that feel much smoother and more comfortable than my old tyres pumped up to 100psi.
Further, the shell fabric, called Vectran, is employed as a breaker belt, which I assume resists punctures, also combines with the high pressure to make for a tyre with a very low rolling resistance. It was noticeable in the 5 Boro Bike Tour how I would just drop away on even the slightest descent leaving the people without hand made, German tyres in my wake.
Next, Sludge. What an inspiring name. Okay, so it's as good a name as Slime, the local bicycle tyre sealant. And of course, who knows if it works or not, because if it is working, you'll never really know ... However, I enjoy the sense of security it gives me, and that's a good thing. 50gms isn't a lot to add the weight of your bike for that sort of confidence. Besides the Contis are probably 50gms lighter anyway. And you really can pour it in through a presta valve. thus using any inner tube you like, even those very fine latex racing inners.
As I said, as to whether this combination works in the long term remains to be seen. But I'm pleased so far.
* see my Bike Index here