Valoria II: Frames and durability

Me:

I noticed that they offer an option for a different, heavier front fork. Why do they offer that? Does it alter the maximum weight rating?

Zach:

Normally the heavier steel fork comes standard on the steel Giro 20 and the aluminum fork comes standard on the Giro A20. The steel fork is offered as a $60 cost saving option on the Giro A20 but doesn’t change the weight rating of the bike. The ultimate durability probably is better for a steel fork than an aluminum fork; likewise with frames. It’s a trade-off between weight savings and durability.

Me:

Is that a tradeoff I should worry about? A few years down the road, if I hit a pothole at 17mph with a loaded bike, am I going to snap the fork or the boom and go tumbling into the hospital?

Zach:

I would think given equal loading and road surfaces, the steel version of both the frame and fork would be less likely to fail, and if they cracked the crack would be more gradual rather than a sudden snapping. I haven’t heard of any aluminium Bacchetta frames failing, but have heard of a couple first generation steel Giro frames failing near where the chainstays are welded to the main tube. I have heard of one aluminium Giro fork cracking near the top of the legs. Long term I’d say the aluminium versions will fail first, but Bacchetta has done a lot of testing on their frames and forks and none of them are likely to fail.

Me:

Just out of curiosity, how does the durability of a Bacchetta compare to the Lightning P-38?

Zach:

In theory a triangulated steel frame like the Lightning P-38 would be the most durable as the loads are spread out over multiple tubes and welds. However the P-38 frame has a reputation for being lightly built, and developing cracks with high mileage riders.

Me:

Hmmm. It sounds like there’s no perfect design.

Zach:

Well, one thing I am certain of, is a suspension greatly reduces the impact loading – to the fork crown, frame, and rider – so in the long run a full suspension bike is likely to hold up better, at least for people who regularly ride rough roads such as those all too common in the Bay Area. Also with suspension you are less likely to lose control when hitting an unseen pothole at speed.