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question about stems(18 posts)

question about stemskushogun
Oct 9, 2001 6:36 PM
Hey everyone. Was looking to buy a stem but really don't know what to get. The ITM Millenium is intriguing, it's light, stiff (from what I hear) and not too expensive. Have heard Deda Newton is kinda fragile. Also heard good things about Cinelli and TTT. Need a 1" Threadless. Also need something that will be compatible with the Easton EC90 carbon fiber handlebars. Any suggestions? Any any good deals out there right now? Thanks a bunch.
stemsTig
Oct 9, 2001 6:50 PM
Here's a 3T Zepp. It is among the lighter stems that I haven't heard any complaints about. I don't know the price, but it's not bad for the quality.
stemsFausto
Oct 10, 2001 4:30 AM
http://cambriabike.com/road/stems/index.htm

The Cinelli Solido is about 15 grams lighter and cheaper than the Zep
Cinelli Solido..tcr01
Oct 10, 2001 5:01 AM
I raced on the 26.0 Solido stem this past season and it worked out just fine. I did however replace the Ti bolts with high strength stainless steel. This just because I am a skeptic of Ti hardware where strength is critical. I also feel this way about carbon fiber.

The Solido is a good bang for the buck. However, I think the TTT Forgie with a 199 Prima bar is a great deal and is a very durable combination while staying just under 380 grams.
Cinelli Solido..Cima
Oct 10, 2001 6:21 AM
tcr01,

My Solido stem is in transit from Cambria Bike to my house, and I'd also consider changing out the Ti hardware. Where did you find the steel bolts to replace the Ti bolts? Is it a pretty standard thread for stems, or Cinelli specific.

Thanks in advance

CC
boltstcr01
Oct 10, 2001 6:58 AM
I got the bolts from a local frame builder. You can order some fasteners from The Third Hand. I think they are M4's(maybe M5's) and I don't no the length off the top of my head. Just measure the ones that come with it. Also, remember to get some flat washers to use with the bolts. The stem uses standard metric threads, nothing proprietary about them.

My main reason for changing these was that Cinelli could not provide me with the grade of Ti that they use for fasteners. The stainless is a strong safe bet that is worth the 5 grams.

You can find the bolts at this link: http://www.thethirdhand.com/index.cgi?c=Parts&sc=Fasteners&tc=Screws,%20Socket%20Cap&id=434700494070
MANY THANKS!!! (nm)Cima
Oct 10, 2001 7:09 AM
Fear of ti?TJeanloz
Oct 10, 2001 7:10 AM
That's a new one for me, and one I don't quite understand. Is the fear here of the bolts that mount the faceplate to the stem? I don't think I've ever seen or heard of a ti bolt snapping off from that kind of force- I've seen the heads snapped off because they were over torqued- but it would take a lot of force to snap one straight off. I'm not saying it couldn't happen, and that it's probably less likely with stainless steel, but it seems to be a pretty improbable scenario.

These things are tested, fairly rigorously I might add, and I don't think it's likely that the bolts would just decide to shear off.

Quick poll: Does anybody have 1st hand knowledge of a faceplate snapping off?
Fear of ti?tcr01
Oct 10, 2001 7:27 AM
Do some research on Ti fasteners and you'll understand the argument. There has been extensive testing on Ti fasteners and the grade of Ti is very important. The fasteners on a stem undergo stress and repeated loosening and tightening for headset adjustment and other maintenance. Even the way the bolts are made such as rolling on the threads verses machining them can make a large difference in the quality and strength of the fastener. These companies do not always test as much as you think. By using cheap Ti bolts they can save a lot of $$$. High quality ti fasteners can cost 5 times or more the price of cheap ones(10 dollars is not uncommon for a single Ti 5mm 6/4 grade bolt with machined threads). If a company can not give me specific information regarding the bolts, I would assume that they didn't put that much thought into the type they specified.

Once again, I recommend you educate yourself much more on the subject before giving your opinion.
I should add...tcr01
Oct 10, 2001 8:10 AM
that I am not scared of Ti bolts but it is proven that even modest steel has a greater weight to strength ratio. The biggest drawback to Ti is galling but can be avoided with anti seize. The problem with Ti fasteners occurs when torsion is applied. They are great if only stressed in tension. In stems, the parts do not fully seat together allowing the bolt to undergo some amount of torsion.

You are correct that the Ti will probably never cause a problem if installed correctly. I just feel that the stainless is a safer alternative. This is just my opinion and is based on what I have read. My main reason for changing out the bolts was the fact that Cinelli gave me a response that made no sense at all concerning the fasteners in the stem. This nonsense answer was even confirmed by a "Ti expert" at Merlin.
Ti Strength to weight ratio is higher than steelchris zeller
Oct 10, 2001 10:39 AM
The strength to weight ratio of Ti is about double that of Columbus steel. However, strength to weight ratio is not important in finding the strongest bolt that will fit a given size die. That is the object here since the size of the die is not a free variable (it is already built into the headset design). Given identical VOLUME, steel will have a higher yield strength than Ti since the greater strength to weight ratio of Ti is due to its lower density. The yield strength of steel and Ti by itself is comparable, slightly favoring steel. However steel has a much higher density and so a steel screw will be slightly stronger than a Ti screw of the same size, but weigh more.
Education,TJeanloz
Oct 10, 2001 9:31 AM
I'll admit to not reading a lot about esoteric subjects like ti hardware. But I think experience probably counts for something. I'm going to estimate that I've sold >2,500 stems. I don't know of any that has sheared its bolts off in the manner that (I think) you're afraid of.

It's like the argument about 6/4 ti being stronger than 3/2.5 ti; I don't dispute it as a fact, but there is a threshold of "strong enough" that 3/2.5 meets. Likewise, I don't dispute your idea that SS is stronger than ti, but from experience I have absolutly no reason to believe that ti doesn't cross the "strong enough" threshold.

If you said you knew 10 people who had this stem and their bolts all broke, then you'd have good reason for concern. But in knowing a lot of people who ride a lot of miles, I've never seen the event you describe.

I re-pose my question: Does anybody have 1st hand knowledge of a faceplate bolt shearing off?
bolts and fearDoubleK
Oct 10, 2001 7:29 AM
Okay, I just have to chime in on this as I work for a fastener company. I also have a Solido stem and was quite comfortable using the Ti hardware that came with the stem. Why, because if you grease the threads and torque the bolts properly, the chances of a catastrophic (sp?) are just as low with them as with the hardware you bought. Why do you think the hardware that you bought from the framebuilder is any better? Because it is grade marked as such and stainless steel? Don't assume that just because a fastener is marked with a specific grade that it won't fail. A fastener is only as good as the process that produces it, not the specs that it is made to. I trust Cinelli's supplier of hardware more than I trust another hardware distributer. This is my choice and I accept the risk. However, to claim that the Ti bolts are suspect is incorrect. You just decided to trust someone else more with your neck. I've seen lots of "high grade" junk over the years.

Ride hard.
ThanksTig
Oct 10, 2001 7:28 AM
The Solido looks like a great stem to consider for my next bike. Thanks for the info.
Very impressed with Zepp. Stiff as . . . whatever is stiff.nmbill
Oct 10, 2001 10:26 AM
nm
re: question about stemsBirddog
Oct 10, 2001 5:07 AM
I use a Ritchey WCS and it is great, but not cheap at near $100.00. Be careful of those bars, a friend of mine who is a very strong cyclist has broken 3 of em and he only weighs about 140. By the way, they didn't just break, they developed cracks that he saw before disaster struck.
If versatility is more important...MrCelloBoy
Oct 10, 2001 6:57 AM
than weight, the Look ErgoStem is worth looking at.
It allows you to adjust height and length in a very wide range, and gives up nothing in stifness.
Available in threadless and threaded.

http://www.adventuresports.com/asap/shops/look/ac-ergo_stem.htm
Ritchey WCSgrzy
Oct 10, 2001 8:54 AM
Bomber design, reasonable price, svelt and shapely!