heds954 Posted January 7, 2012 Report Share Posted January 7, 2012 Ok, Titanium bolts for brake discs, are they a good idea or should one stick to OEM bolts. If Ti is ok, should you use a specific assembly compound or will plain old Copaslip do? But then wouldn't using either affect torque values and possibly mean that you could over tighten and compromise the strength of the bolts? I've had a search on the forum but couldn't see anything applicable in this scenario, any informed assistance would be much appreciated. Edit: to add Oh, and if anyone can get decent bolts that will do the job at good rates then please let me know Link to comment Share on other sites More sharing options...
Superdunc Posted January 7, 2012 Report Share Posted January 7, 2012 A well designed grade5 Titanium bolt has a slightly higher tensile strength than a standard grade8.8 bolt. I've always torqued them the same as a standard bolt. Copperslip is fine, though there are more specialist alternatives, it's important that you lube the underside of the head aswell as the threads. I've got a chart somewhere that came from an F1 team which specified torque settings for bolts with various lubes, basically you reduced the Torque settings by about 10% when lubed, though most torque settings in manuals ater the libed figures. On a road bike I'd be looking at running thread lock on disc bolts rather than copperslip. Link to comment Share on other sites More sharing options...
heds954 Posted January 7, 2012 Author Report Share Posted January 7, 2012 Ah, now, funny you should mention it, but I had my OP all planned out in my head and completely forgot to mention thread lock. Thread lock would be my preference. However, I am aware that mating Ti to anything else needs a barrier to stop the reaction which would cause a seize. Thing is, you only need a small blob of thread lock and that wouldn't be enough to cover the whole of the mating surfaces. So, thread lock or assembly paste, as I'd imagine that using the two together wouldn't work Link to comment Share on other sites More sharing options...
flashgordon69 Posted January 7, 2012 Report Share Posted January 7, 2012 Ive got Titanium disk bolts on my bike They came from Probolt and I use copper slip on them I wouldn't use thread lock on them as if you leave them on for a while you will not get them back off without damage Ive never had any problems not using thread lock Link to comment Share on other sites More sharing options...
Egg on Leggs Posted January 7, 2012 Report Share Posted January 7, 2012 Had Pro Bolt Ti on my VTEC for years now, just put them on to original spec torque, never had a problem. Link to comment Share on other sites More sharing options...
heds954 Posted January 7, 2012 Author Report Share Posted January 7, 2012 Ive got Titanium disk bolts on my bike They came from Probolt and I use copper slip on them I wouldn't use thread lock on them as if you leave them on for a while you will not get them back off without damage Ive never had any problems not using thread lock So you wouldn't use thread lock and torque them to their stated values, but you use copaslip which means that you be using inappropriate torque values, but then by using thread lock you risk the bolts never coming out without a fight ...gahhhh!!! Link to comment Share on other sites More sharing options...
heds954 Posted January 7, 2012 Author Report Share Posted January 7, 2012 Unless it's a race bike where you're swapping discs regularly apply threadlock. Hydraulic action will ensure that the threadlock is evenly coating the threads. Threadlock application doesn't alter torque settings. I've removed many a threadlocked bolt to find that the threadlock barely covers anywhere other than where you put it in the first place. So would this still mean risking a bare interface between Ti and it's mating surface and the resulting seize? Link to comment Share on other sites More sharing options...
Superdunc Posted January 7, 2012 Report Share Posted January 7, 2012 I've removed many a threadlocked bolt to find that the threadlock barely covers anywhere other than where you put it in the first place. So would this still mean risking a bare interface between Ti and it's mating surface and the resulting seize? The stuff you've seen heds is the factory applied stuff which apllied to the bolts by the supplier in a form that dosn't flow so the bolts can sit on the shelf until they are needed in production, the thread lock only sets when it is starved of oxygen. It's basically the same as what we buy over the shelf but in a different form. I still like to put a little copperslip under the head of ti bolts to stop them gauling. Link to comment Share on other sites More sharing options...
heds954 Posted January 7, 2012 Author Report Share Posted January 7, 2012 I use the very same Loctite products (nut strength and stud strength), I was taught by a friend who worked as a car mechanic to run a bead of threadlock near the bottom of the thread and then run it around until it met itself and then use it. On removal I've never found that the threadlock has moved that much further up the thread. On the one occasion where I did liberally cover a thread I found that the force needed to remove the bolt sheared the head, and when undoing bolts where others have liberally used threadlock on bolts (eBay stuff) the heads have suffered (female allen bolt heads - fuggin things). So I've always tried to remain fairly cautious about using too much. Thing is I have some decent wheels to go on my bike with some new discs and I thought I'd go the whole hog and use Ti bolts to finish it all off. But I'm a bit hesitant to just jump in without any forethought in case I muller the discs or especially the wheels. Link to comment Share on other sites More sharing options...
Cibbersicks Posted January 7, 2012 Report Share Posted January 7, 2012 When fitting my discs to my new wheels, I'll be using Ti bolts. I intend to do them the same as I have before, a liberal dab of Loctite on the thread, allow it to flow over the body of the thread, then tighten to the specific torque. Of course tightening the bolts in proper sequence alternating across the face, rather than around the circumference. Never had any problems with this theory, I am open to being told different though! If you're that bothered spray the bolts with proper nickel anti seize aerosol spray and tighten the fasteners and torque witness mark them... Yup, every time EDIT: Oh and I'll be using flanged hex bolts as allen socket bolts suck Link to comment Share on other sites More sharing options...
heds954 Posted January 7, 2012 Author Report Share Posted January 7, 2012 If you're that bothered spray the bolts with proper nickel anti seize aerosol spray and tighten the fasteners and torque witness mark them... Well, yes, I am that bothered as I don't want to muller the discs and wheels. Is there a nickel anti seize aerosol that you'd recommend? I've just had a hunt around for the Loctite version which is being sold everywhere in the US (even on eBay!) but not in the UK it seems. @Cibbers - yes, allen socket bolts suck and blow at the same time. Where are you getting your flanged hex bolts from, I'm curious? Link to comment Share on other sites More sharing options...
Cibbersicks Posted January 7, 2012 Report Share Posted January 7, 2012 Actually, this has just reminded me, I'm going to have to find the specified torque value for these wheels.... Link to comment Share on other sites More sharing options...
Cibbersicks Posted January 7, 2012 Report Share Posted January 7, 2012 Well, yes, I am that bothered as I don't want to muller the discs and wheels. Is there a nickel anti seize aerosol that you'd recommend? I've just had a hunt around for the Loctite version which is being sold everywhere in the US (even on eBay!) but not in the UK it seems. @Cibbers - yes, allen socket bolts suck and blow at the same time. Where are you getting your flanged hex bolts from, I'm curious? Will be ProBolt, I'll PM you in a sec Link to comment Share on other sites More sharing options...
svingel Posted January 8, 2012 Report Share Posted January 8, 2012 Lockwire? Not scientific, and not by the book, but in 200000 kms of road riding, I've never used anything other than copaslip, for disc and caliper bolts. And never had one come loose. I do torque them to normal specified value. A theory I've heard about torque values for lubed bolts, is that(more of) the force applied, when tightening the bolts, is used putting the bolt under tension, instead of getting lost in transfriction..Well, that should've been "overcoming friction", but I got a little Johansson'ed. Link to comment Share on other sites More sharing options...
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