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Are Ti bolts as dangerous as I think they are?(10 posts)

Are Ti bolts as dangerous as I think they are?sprocket rocket
Dec 30, 2002 5:06 PM
I had a sudden bolt failure on my Zepp stem. It was on the carbon steerer side but I dont want to think about what would have happened if my faceplate bolts gave way. I replaced the two Ti bolts on back with stainless ones since I am always having to adjust my headset every few hundred miles or so (carbon steerer with the ever so crapulent Easton Compression plug).

I am wondering if the risk of Ti Bolts are worth saving two or so grams of weight. I know what you guys are thinking - I use a torque wrench religiously.
Sounds like you've answered your own question (nm)Kerry
Dec 30, 2002 5:44 PM
ask on MTBR's weight weenies forumweiwentg
Dec 30, 2002 6:22 PM
for road bikes, stuff like ti faceplate bolts are safer (although some Zepp stems have had problems with theirs). from a logical perspective, no, ti bolts aren't worth it. if you have the dough, then of course there are a lot of bolts where titanium or aluminum can be safely used.
re: Are Ti bolts as dangerous as I think they are?Ambishawn
Dec 30, 2002 9:47 PM
Ti bolts are a waste of money. The steel alloys in high grade bolts are far stronger than titanium and stand up much better to repeated disasenbly. As far as dangerous is concerned it depends on the application. Where on the bike, How big and strong the rider, what kind of riding? If your in the Parrinees on stage 13 of the Tour de France you may benifit from the weight savings of lots of ti bolts. You probably would weigh only 145lbs and the bolts need only to last for 100 miles or so to the next stage. For most of us Ti bolts are too much trouble and too much money for us.
re: Are Ti bolts as dangerous as I think they are?Juanmoretime
Dec 31, 2002 3:01 AM
I've had good and bad experiences with titaniums bolts. Ti bolts like to be set and forgotten. They appear to become weaker when subjected to frequent loosening and re-torquing. To sum it up, they are OK if it's not a bolt you will be loosening frequently. So if you one of thoses constantly adjusting your position on the bike, go with stainless steel.
re: Something else is wrong too.................Rusty Coggs
Dec 31, 2002 5:40 AM
If you are continually having to readjust the HS. The plug has nothing to do with holding the adjustment after it is properly made.
re: Something else is wrong too.................pa rider
Dec 31, 2002 7:37 AM
Rusty is correct, because your stem bolts keep the headset tighten, not the cap. The headset cap is used to put pressure on the headset until you tighten the stem bolts.
can you generalize?DougSloan
Dec 31, 2002 7:59 AM
Ever think that bolts might vary a bit, just like lots of other components? Might as well ask, "are Ti frames as dangerous as I think they are?" because you heard of one breaking.

I have used lots and lots of ti and even al bolts. I've never had any break or strip. I replaced nearly every bolt in my DA group with SRP ti and al bolts. No problems.

I'm careful to use anti-seize, torque properly (by feel, no less), and thread straight; I'd do all this even if they were aircraft quality steel bolts, too, though.

There could be an anomaly that caused your failure that had nothing to do with the type of metal, like bottoming out, cross theading, bad threads, contamination, etc.

The weight savings is certainly miniscule for any particular bolt; for the same dimensions, ti is about 1/2 the weight of steel, and al is 1/3 of steel. For the entire DA group (except for hubs), using all SRP ti and al bolts available saves about 90-100 grams. That's almost a quarter pound, which is huge IF you are a weight weenie. I think the only al bolts used were the RD pulley bolts, the RD main bolt (which is huge), and bottle bracket bolts. You could go al crank bolts, but that seemed a little too much for me. The al RD main bolt is actually a good idea, as it is designed to break away in a crash, rather than screwing up your frame.

Bottom line: one way or the other, I don't think you can gernalize from one observation, positive or negative.

Here's what SRP has to say (understanding their innate bias):

2. Are Titanium (Ti) bolts as strong as the steel ones they're replacing?

For the most part, yes. Ti is as strong as steel in sheer strength (twisting torque) so you can tighten it just as tight as you can tighten a steel bolt. And due to its superior corrosion resistance, you actually get a net gain in overall integrity when installing our Ti fasteners. Be careful, though, as Ti is a little softer than steel so you can strip it just a bit easier. ALWAYS use a fresh Allen key with no signs of rounding on the edges. Even an expensive ball-end allen key can round off so always be sure to visually inspect the key before inserting it. And be careful and make sure it is inserted all the way in before you apply torque on it. 99% of stripped bolts are caused by either round allen keys or by shallow key insertion.

http://www.srp-usa.com/faq.htm

Doug
FYI the original Ti bolts were 2gms the stainless ones are 3gmssprocket rocket
Dec 31, 2002 11:29 AM
I actually ground the head walls thinner since the torque applied to them are so light. Before my stem weighed 130 gms and now it weighs a whopping 132 gms.

I agree with you that I was skittish about torquing my stem bolts too much causing the headset to loosen prematurely. Then by having to constantly adjust the headset I prematurely fatigued the ti bolts.

Live and learn.
I can honestly say...laffeaux
Dec 31, 2002 9:03 PM
Two grams does not make any difference what so ever. Go with either. I have TI bolts on a MTB stem, and the bolt heads deform way too easily. After a few removals, it's tough to make the allen wrench fit into the bolt head.