Rick Harker wrote:
The reason for so many thoughts is because I've entered in a charity ride here in Melbourne with a 210 Km distance in one day. Scares me a little and I don't have the confidence yet with my Sofrider to ride that distance. Last year they had 14,000 entries.
I'm gunna have a go though...
Doing the
Around the Bay in a Day ride, eh? Good on ya
I've not done it myself yet but I will do when I get a chance. As it's not until October I'm sure you've got plenty of time to train up for it, just keep clocking up the km's and gradually increase the distance of the longest rides you do. I gather that the Around the Bay routes are fairly flat too, so that will help. Anyway, I think it's fantastic how many people take part each year, the 250km and one of the 210km routes are already sold old! :shock: (the numbers for three of the route options are limited because they involve ferries)
Regarding the difference in speed between different bikes, you're spot on with your guess it's mostly about the 'engine'
Aerodynamics of the rider is the next most important factor (i.e. riding position make a big difference, it's why recumbents and TT/Tri bikes are noticeably faster than road bikes, which are in turn noticeably faster than hybrids, etc.), after that comes rolling resistance (good tyres are a relatively cheap upgrade with a potentially big payoff), and the least important factors are bike wheel aerodynamics, frame aerodynamics and bike + rider weight. There's a good discussion of this stuff
here, and here's an illustrative quote:
BikeTechReview wrote:
Roughly, the average rider power requirements on a course with a zero net elevation gain is broken down into 60% rider drag, 8% wheel drag, 8% frame drag, 12% rolling resistance .5% wheel inertia forces and 8% bike/rider inertia. The uphill TT example given is a special case where the rider aerodynamics and the bike/rider weight have nearly equal contributions to power – somewhere around 35% each with wheel mass contributing around 1%. The steeper the hill, the more important mass becomes and the less important aerodynamics becomes. In all cases, however, there is approximately 3% of the average power unaccounted for.
Regarding a Silvio versus a Sofrider, well thepretically the Silvio would indeed be faster as the slightly lower seat height is probably a little more aerodynamic, the bigger 700C wheels with narrow high performance tyres will give lower rolling resistance and better wheel (tyre, mostly) aerodynamics, and the lower weight will help uphill. The racier handling and more sophisticated suspension may enable you to corner faster too. How much speed difference all that adds up to I couldn't say, we need the opinion of someone who rides both regularly. You could probably make up most of the difference by converting your Sofrider to 700c wheels, but the Silvio still seems tempting though, doesn't it?
I must admit I'm considering one myself... :roll: