They sometimes do that sir

[siwes]

Has anyone had that horrible saying "they do that sometimes sir" this was a bottom pulley bolt snapping on my Griff 500 nasty clunking under the bonnet, low loader and waving goodbye to my precious. Is there a high tensile bolt that can be fitted , or is this just a weakness
regards Si

[apache]

Blimey!...not having much luck are you Simon....I've never heard of this particular quirk

[shpub]

Adrian Venn did this on his significant other's car when tightening the thing up. Pretty rare but not totally unique.

Steve
www.tvrbooks.co.uk

[jasoncook]

my bottom pulley bolt snapped luckly i just drilled it out and fitted a new bolt.Imet a chap with a griff who i sold a dash to and he had the bolt snap on his .

[deltaf]

Check out a company called Mr Fastener.
They do all sorts of bolts and do kits mainly for bikes.
Id suggest replacing that bolt with a Titanium replacement, it wont snap again and is lighter.

[GreenV8S]

Has anyone had that horrible saying "they do that sometimes sir" this was a bottom pulley bolt snapping on my Griff 500 nasty clunking under the bonnet, low loader and waving goodbye to my precious. Is there a high tensile bolt that can be fitted , or is this just a weakness
regards Si

It has to be done up to some incredible torque because the bottom pulley acts as a torsional crank damper. I imagine the standard bolt will be high tensile as standard.

[MEMSDesign]

deltaf said:Id suggest replacing that bolt with a Titanium replacement, it wont snap again and is lighter.

Don't think that Titanium is stronger than high strength steel. It isn't.

[trackdemon]

:schoolplaygroundmode:
Oh yes it is!

PS

Depends which titanium

[MEMSDesign]

trackdemon said: :schoolplaygroundmode:
Oh yes it is!

:schoolplaygroundmode: Oh no it isn't.

UTS for Titanium Ti-15Mo-5Zr ST 730°C, Aged 400°C is (high strength titanium alloy) is around 1700MPa. VascoMax® C-350 Speciality Steel UTS is around 2310MPa.

Like you say, it all depends on the specific alloy/heat treatment. It's not a foregone conclusion that Ti is always stronger than a high strength steel.