I examined the tyres of my Quest today. There was a sort of wave in the right front tyre; maybe one of the two woven layers was torn ? This tyre had rolled 4200 kilometers and it seems that that is the distance it will serve my velomobile reliable.
I have checked the pressure weekly and seldom had to add some air to keep the pressure at 6,5 bar. It is clear that the steering front-tyres under a velomobile are undergoing a war of attrition when turning at high speed on the stony cycle paths.
Normally I’m a easy-going cyclist who loves the comfort of a fully fairing and most cycling paths during my commute are made of smooth and silky asphalt. That is why I put comfort and reliability before speed. The HPV’s at the front gave me a feeling of trust when steering on winding paths and the Schwalbe Marathon Extreme at the back wheel never broke out or slipped away. I think the Marathon Extreme can do another 4000 kilometers 😉
Authority’s on aerodynamics have written that the resistance of a racing bicyclist is mainly due to air resistance and only a small part due to rolling- and drive resistance. Because the ideal fairing of a Quest is already reducing the air-resistance to the practical minimum, it becomes an impossible story to reduce the rolling resistance at such a level that it can be felt when cycling. I decided that the comfort that the wide HPV tyres gave me the last 4 months (4200 km’s) is more important to me than the minimum decrease of speed. They were not 100% puncture resistant, but I reckon that once per 2000 kilometer is acceptable. There is a nice article written in CYLINGNEWS ; they explain very clearly the logics of rolling-resistance here. When reading; be aware of the fact that the wheels of a Quest are inside the fairing !
The story continues here.