Rotor bolts weigh weenying- advice please- Ally/Ti mix of bolts.

You hear about die hard racers running 3 bolts on their disc rotors instead of 6. I kinda want to lighten things up, so how about this….

On each wheel…

3 full strength (but expensive) Ti bolts
and
3 light and cheaper (and gross colours) Ally bolts

Is there any especial reason to not mix em?

I figure that if they’re all done up tight, they’re doing the job and if anything broke, the Ti ones would hold things together.

Whatdaya reckon engineering types?

And before anyone pipes up, yes I know that this is a bit of a waste of time, but I for once don’t mind.

You’d save more weight by having a good dump before you set off.
I wouldn’t want to mess about with something that critical for the sake of it.

I have 6x Ti rotor bolts on mine, no problems, what’s your issue ?

nouveau – Member
I figure that if they’re all done up tight, they’re doing the job and if anything broke, the Ti ones would hold things together.

Leave the alloy bolts out then!

run 6 ti ones if you feel the need.

i’ve seen 3 steel bolts being used without breakage on a dh bike so it works. I wouldn’t go for less than full-compliment of ti bolts personally as ti has a pretty low shear strength compared to steel.

the question I’d be asking if I were that way inclined, are 3 steel and 3 ally bolts lighter than 6 ti bolts.

are 3 steel and 3 ally bolts lighter than 6 ti bolts

No.

Use 3 steel bolts but drill them out.

Winnah!

Drill the rotor full of holes so there is almost nothing left of it.
Or wear a rotor right down to the thickness of a razor blade.
Much lightness!

You could save more rotating weight by drilling the middle out of the bolts making them hollow, drill holes in your rims between the spokes and trimming down tyre knobbles.

you could probably drill holes in the side of the centre tube part your hubs to save a bit more. brake rotors could be whittled down a little thinner. Round all sharp corners off to a nice big radius removing excess material.

Get drilling, filing, sanding and polishing as much as you dare.

That’s the thing, ti bolts are a bit expensive and I don’t really want to start destroying things with a dremmel and I don’t have a CDT workshop at home…

I am just being a tightarse, aren’t I? I kinda bet it’ll work…

Go brakeless?

I’d get any amalgam fillings removed next time you visit the dentist, too.

You will save more by drilling a hole in the pads. Or use smaller discs. Are you really serious or have we all fallen for a troll ?

i know someone who races xc and only uses 3 ti bolts. he does only weigh 60kg though…

definitely a troll.

When running 3 bolts do they remove the spare hub and rotor tabs?

Actually ive got an alloy bolt in my tool box, when I pick it up I cant actually tell if it weighs anything, its so light. But I wouldnt want it holding my rotor on. Thats daft – escpecially as I weigh 85kg naked.

Its quite amusing looking at that weight weenie sight for how they save weight though.

Hm.. honest, I’m not taking the piss (or whatever the current web term is for that, why trolling? It sounds mucky. Why not something to do with the Emperor’s new clothes?).

But I am being a bit soft in the head for sure. I’ve just ‘gone tubeless’ and the thing is that Stan’s lie about the weight of their kit to such a great extent that my new set up is heavier than the old. Only by a couple of hundred grams though, so I was thinking that a few quid at the bolt shop may tip the balance back.

One thing is… People always say ‘go for a dump before you ride’. I mean, that’s a given before a race… That mix of nerves and espresso. The portaloos at 24 races take a right battering. Worse than Donnington I’d reckon.

Anyway, thanks for your valuable help everyone!

So just what does you bike weigh then ?

Have you tried helium in your tyres?

tragically1969 – Member

are 3 steel and 3 ally bolts lighter than 6 ti bolts

No.

Whilst true the difference ain’t much. A titanium set weighs approx 10% less than a 50/50 steel/aluminium mix.

Was sub 19lbs once…

I never took you for a weight weenie Nouv, good work.

Seeing as aluminium bolts are about as much use as choloate teapots (or chocolate bolts of that matter) why bother?

Seeing as aluminium bolts are about as much use as choloate teapots (or chocolate bolts of that matter) why bother?

They hold my brake clamps, shifter clamps and water bottle cages to my bike just fine and dandy.

Possibly (fractionaly) better than chocolate:
http://www.nylonalloys.co.uk/cgi-bin/shop/nylon-alloys-subcategories.pl?NYLON|METRIC|SCREWS

Hm, I’m with KingTut on ally bolts in the right application….

The old wheels have ally nips (OK, they’re kinda nuts rather than bolts), but I’ve had 8 years out of ’em before one nipple broke. More reliable than the steel spokes!

Why is your tubeless system heavier?

tragically1969 – Member

are 3 steel and 3 ally bolts lighter than 6 ti bolts

No.

Whilst true the difference ain’t much. A titanium set weighs approx 10% less than a 50/50 steel/aluminium mix.

So to summise, No, again….. 😉

I changed all my bolts to Ti, except the stem ones (just felt a step too far), even on the mechs. Same strength as steel, but lighter – no problem.

And I do usually have a good dump before riding.

Well…. Stan’s rims aren’t as light as promised and Hope SS hubs are lumps! Although a switch to ti bolts there should swipe 50g off there. Plus the tyres are heavier than the lack of tube is lighter (if that makes sense). Yes this is pretty bad weight weenying, isn’t it?

However, it does mean I can use gold and purple bolts! GO VEGAS!!

To run at lower pressures I assume the sidewalls have to be a bit thicker, so tubeless is sometimes heavier than tubed tyres.

Stop using UST tyres then, normal tyres are fine and you’ll get back your 200g.

Yeah… I got Bonty ‘tubeless ready’ ones- They’re pretty light, but would you believe, heavier than a mostly worn out Maxxis Larsen 1.9″!!

Are you on crack?

Sounds like there are plenty other places you can save weight before going for the safety critical!

Tyres would be a good start. Non ust ones.

Post the rest of your spec too.

I’m trying to steer clear of the toxic rock these days!

Bike.. hmmm

Kona Kula- (Easton Elite) modified with track ends and disc mount.
Pace RC31 fork
CK headset
Hope SS/ProII hubs
Stan’s Olympic Rims
Rev spokes
Ally nips (purple and gold!)
Thommo post/stem (yes a wee bit heavy, but looks lovely and I need a reliable 400mm inline post for sure)
S&M grips from the BMX shop!
FSA “Pro” carbon riser of some kind (same as KingTut’s!)
Shimano XT Servowave discs
Ashima rotors
Bonty MudX 1.8 tyres for the winter goop (prob Maxxis Larsens again in summer- love ’em)
Selle San Marco saddle (light and racey kinda job with ti rails)
Race Face Turbine LP 180mm cranks, and
Sq taper RealSeal BB (is HTII really ligher? Doesn’t seem to be. Plus they seem to be terrible in the wet).

Any suggestions? The wheels and brakes are new, but everything else seems light to me and has done season after wet season with no real complaints.

I quite fancy some of those light Formula brakes! Who wants to sponsor me? Are they any good?

You put track ends on a kula? Clearly no internet opinion will keep you from running less disc bolts… or was that when you were on the toxic rock?

“I need a reliable 400mm inline post” and yet reliable brakes are not on the list? Is the post at least a Masterpiece? If not, lighter post would save more and be more sensible than rotor bolts. Likewise stem.

Also, why do you want it lighter? I suspect it’s not so you can ride faster or further. Lets be honest, if you wanted to go faster or for longer, a sus fork and gears would be next on the list…

If it’s “just because” (and fair enough) then I’d be looking at tyres (non ust), seatpost, stem in that order.

Also what pedals? And what kit do you ride with? Shoes/helmet/bag (fairly racy setup so I’ll assume no bag?) are other places to loose more weight…

Grips, seatpost, stem, brakes.

3 ti/3 alu bolts will be fine, I know a couple of people doing it, also know a few running 6 alu ones. I’m tempted to try it! I reckon with 6 bolts itd be fine!

So to summise, No, again…..

Exactly.