Bollocks! It's done it again!

[mangocrazy]

I only got titanium caliper bolts in the first place as the bike decided to eject one of the stock bolts a couple of years ago.

Trundling along yesterday leading a rideout and what happens? Horrible noise from the brakes and lots of clonking from the front end, pull over and find a nice shiney expensive titanium caliper bolt is missing.

Errm, I was under the impression (from racing chaps I've spoken to) that titanium has a 'life' and must be replaced at set intervals (dunno what they are) and also that they are not recommended for stressed applications such as caliper bolts. Only recommendation I know of for caliper bolts is High Tensile steel.

I do know that Steve Cull had a potentially fatal incident involving a titanium caliper bolt snapping on his RS500 Honda quite a few years back at the TT. He was OK but it could have been much, much worse.

[Nooj]

Dunno, not heard any of that. Titanium is VERY strong stuff and I'd be surprised if anything me or my bike can do to it will stress it to breaking point.

Could be that was the case a number of years ago before it got to be less specialised stuff. Aluminium forging and casting techniques have moved on a lot in the last few years, so I'm asuming it's the same for titanium, especially now it's so much more wide spread in production applications.

[Falcopops]

I'd be inclined to agree with Mangocrazy on this, but purely due to a lengthy discussion with a chap in the Melbourne Ducati Dealership.

I was looking for cap headed caliper bolts to go with the Ohlins forks for the Falco and tried them on the off chance, but they only had 3 and they were in Sydney.

Anyway the chap I was speaking to was your typical older guy and just wanted to talk, I had the time so I let him. Very interesting stuff about all sorts, but he also raised the point about Titanium being a serviceable part and advised me against using Ti bolts. He agreed that they were plenty strong enough to cope with the stresses and strains, but did have a life expiry. Unfortunately I didn't ask how long that was.

Not a definitive answer and I can't back it up with solid evidence, but I had a feeling this bloke knew what he was on about. He quoted a history with TWR and GT40 development and racing as well as bikes.

[Kwackerz]

http://homepage.ntlworld.com/webzxr/zxr ... emods.html

As I had heard, you can use Ti but it needs to be the right grade.

On the subject of brakes, aluminium brake line ends are a big no-no... thought i'd throw that in while the subject is about...

[mangocrazy]

Hmmm there's a whole titanium world out there I never knew about. Apparently there are 28 grades of Ti... But grade 5 does seem to be the one for caliper bolts.

For brake line ends I would never use anything other than stainless, personally.

[Nooj]

I knew about ally banjos being no good for street use due to corrosion. The titanium bolts I have are 6Al-4V 'aircraft grade', a titanium aluminium vanadium and molybdenum alloy, tough as old boots. No idea what the life expectancy is and I'm not going to worry about it. I was tinkering with a Tuono yesterday that turned out to have a sheared steel engine bolt. If it's gonna go, it's gonna go regardless of what it's made from, but I reckon £££s worth of Ti will out last what ever cheap steel motorcycle manufacturers choose to make their fixings from.

Besides, if it becomes a habbit of my bike, they'll all have fallen out way before they get old enough to break