4mm screws that take 5mm Allen key? (thinly-disguised rant...)



RE/
>Having stripped out a few 5mm stem clamp bolts, I welcome a manufacturer who
>specifies torque for their fasteners.


Reading Thompson's instructions, I came away with the notion that the whole
friggin' thing will fail if over *or* under torqued.

OTOH, maybe it's the lawyer's talking...but it doesn't exactly give me a warm
and fuzzy feeling...In someething like a stem, if bulletproof and sophisticated
collide, I want bulletproof.
--
PeteCresswell
 
"(Pete Cresswell)" <[email protected]> wrote in message
news:[email protected]...
> RE/
> >Having stripped out a few 5mm stem clamp bolts, I welcome a manufacturer

who
> >specifies torque for their fasteners.

>
> Reading Thompson's instructions, I came away with the notion that the

whole
> friggin' thing will fail if over *or* under torqued.
>
> OTOH, maybe it's the lawyer's talking...but it doesn't exactly give me a

warm
> and fuzzy feeling...In someething like a stem, if bulletproof and

sophisticated
> collide, I want bulletproof.


Thomson stems and seatposts are both bulletproof and sophisticated. They're
one of those things you can bolt on your bike and simply forget about. I
run their seatposts on all my bikes, three are DH bikes. I've seen DH seats
ripped off their rails and the Thomson dutifully holding on the bent and
twisted rails. Pete F. has a pic of one with a bad dent in it from a rock
but from what I could tell from the pic it was still working for the ride
home.

Mike
 
"John Morgan" <[email protected]> wrote in message
news:pBDDc.11835$6r1.9354@fed1read06...
> KLydesdale wrote:
>
> > You should just grind slots in all the fasteners on your bike. That way
> > you only have to carry a flat-bladed screw-driver.

>
> Why? I'd rather just carry a multi-tool with the common size hex wrenches
> in it.


He forgot the smiley.

--
Phil, Squid-in-Training
 
> The only explanation I can come up with is that since there are 4 bolts
> holding the face plate to that stem, they decided to go with a smaller

bolt
> to save weight. You see the 2-bolt stems all have big thick bolts because
> they have to bear twice the load.
>
> I have Thomson stems on two of my bikes, and I have to say... I'm not that
> impressed. They aren't that light and they aren't that easy to adjust (4
> bolt face plates are a pain to torque properly without binding!). I don't
> like the eccentric steerer clamp, as it, too, is more difficult to adjust.
> They *do* say "Thomson" on them, but I see myself going back to a lighter
> weight 2-bolt stem on my next bike.


Ugh... 2-bolts are incredibly flexy (the bolts do virtually nothing in
response to torque around an axis through the center of the bike and
handlebar)... on the magnitude of an inch of deflection at the ends of the
handlebars!!!

Stem in question: Salsa Moto-Ace. Replaced with a Ritchey Pro 4-bolt (even
lighter) and no such flex. I'll NEVER go back to 2-bolts...

--
Phil, Squid-in-Training
 
(Pete Cresswell) wrote:

> Reading Thompson's instructions, I came away with the notion that the whole
> friggin' thing will fail if over *or* under torqued.


Is this the first instruction manual you've read? I think most cover their
asses in much the same way...
 
"(Pete Cresswell)" <[email protected]> wrote in message
news:[email protected]...
> I'm setting up my new semi-custom FS. LBS said that Thompson's

super-duper
> stem was the only one that fit the size/angle spec, so I said "OK".
>
> I'm putting this thing together and grab my trusty 5mm allen key that fits

all
> the brake screws, the saddle adjustment screws, the seatpost clamp
> screws....even the cap screw on the steering tube.... and probably a few

more
> things that don't come to mind right now...
>
> Oops...some genius has used 4mm screws on the Thompson stem's clamp.
>

<Snip rant>

I understand your frustration but I think there are valid reasons Thomson
chose 4mm bolts. As someone else mentioned this allows more material to be
used in the actual stem, but also I suspect it lessens the chance of an
over-zealous mechanic applying too much torque.

And if you think 4 bolt face-plates are too much hassle, have a look at this
little beauty:

http://www.alansbmx.com/product_info.php?cPath=32_47&products_id=1024

Steve.
 
ZeeExSixAre wrote:

> Ugh... 2-bolts are incredibly flexy (the bolts do virtually nothing in
> response to torque around an axis through the center of the bike and
> handlebar)... on the magnitude of an inch of deflection at the ends of the
> handlebars!!!


Agreed. 4 bolt clamps are the way forward.
 
S o r n i wrote:
> KLydesdale wrote:
>> "(Pete Cresswell)" <[email protected]> wrote in message
>> news:[email protected]...
>>> RE/
>>>> "WARNING:
>>>
>>> It gets even better: "WARNING: Torque Wrench Required For
>>> Assembly....".... well, I guess my comments about ease of adjustment
>>> in the field were kind of off-base...
>>> --
>>> PeteCresswell

>>
>> Having stripped out a few 5mm stem clamp bolts, I welcome a
>> manufacturer who specifies torque for their fasteners.

>
> You mean you're actually supposed to /adhere/ to specs?!?
>
> Bill "fascinating concept" S.


Only if you make the mistake of reading the instructions first.

Parbs
 
"(Pete Cresswell)" <[email protected]> wrote in message news:<[email protected]>...
> I'm setting up my new semi-custom FS. LBS said that Thompson's super-duper
> stem was the only one that fit the size/angle spec, so I said "OK".


[snip]

I might have missed it, but here's something that might be a benefit:

Since manny of the other fasteners on a bike are 5mm, that's all a
thief needs to really take a good load of gear. Like a really nice
Marzocchi fork - undo the QR, use your trusty 5mm to undo the stem,
walk off with a $500 fork.

I REALLY like the way the Thomson clamps the steerer. My knees are
very thankful. That feature alone is worth it to me. And weight? If
you wanted featherweight, get a Moots Ti stem. Sure, it's over $200,
but it's way cool. :)

I have a set of hex head sockets. After it's all hand-tight, I go
back and torque it down using a torque wrench. No different than any
other bike fastener. And with a glob of grease on the threads and the
back of the bolt head, I have never had a single binding problem. I
dunno, it's just not much more complicated than a 2-bolt stem, nor are
the instructions any more lawyerese than any other product. Read a
Marzocchi owner's manual. Sheesh.

The reason I went to Thomson for seatposts was the high degree of
adjustability of the seat angle, but more than that, *no setback*.
But I chose the stem specifically for it being a four-bolt face.
--
Jonesy
 
> Is this the first instruction manual you've read? I think most cover their
> asses in much the same way...


Most of the stuff I buy is below the level at which mfrs provide instructions.
 
RE/
>Ugh... 2-bolts are incredibly flexy (the bolts do virtually nothing in
>response to torque around an axis through the center of the bike and
>handlebar)... on the magnitude of an inch of deflection at the ends of the
>handlebars!!!


Although I can distinguish between the flex inherant in the 5" risers I was
using and that from the 2-bolt stem what was on there with it; it's obvious even
to me that the new setup with 2.5" risers and the Thompson stem is a *lot*
stiffer....rock-solid, even.....and that's the main reason I went over to a
semi-custom bike - to get the extra steering tube so I could mount a normal
bar/stem setup.
--
PeteCresswell
 
"ZeeExSixAre" <[email protected]> wrote in message
news:[email protected]...
>
> "John Morgan" <[email protected]> wrote in message
> news:pBDDc.11835$6r1.9354@fed1read06...
> > KLydesdale wrote:
> >
> > > You should just grind slots in all the fasteners on your bike. That

way
> > > you only have to carry a flat-bladed screw-driver.

> >
> > Why? I'd rather just carry a multi-tool with the common size hex

wrenches
> > in it.

>
> He forgot the smiley.
>
> --



I forgot how to do the one showing tongue firmly implanted in cheek.
 
"PeteCresswell" <[email protected]> wrote in message
news:[email protected]...
> > Is this the first instruction manual you've read? I think most cover

their
> > asses in much the same way...

>
> Most of the stuff I buy is below the level at which mfrs provide

instructions.

No need to consult the instruction manual for those specs on some stems.
Check out the fine print on the faceplate of this Specialized one.

http://www.specialized.com/SBCEqProduct.jsp?spid=5062&JServSessionIdroot=f0r
ostvr16.j27010

Now somebody's thinking!
 
KLydesdale wrote:
> "PeteCresswell" <[email protected]> wrote in message
> news:[email protected]...
>>> Is this the first instruction manual you've read? I think most
>>> cover their asses in much the same way...

>>
>> Most of the stuff I buy is below the level at which mfrs provide
>> instructions.

>
> No need to consult the instruction manual for those specs on some
> stems. Check out the fine print on the faceplate of this Specialized
> one.
>
>

http://www.specialized.com/SBCEqProduct.jsp?spid=5062&JServSessionIdroot=f0r
> ostvr16.j27010
>
> Now somebody's thinking!



Have you seen some of Specialized's short road stems? Check out an Allez or
Roubaix and look closely at the body of the stem... the tribal-looking lines
on the stem are actually tiny tiny words... the standard fare of course
(alloy, heat treated, torques, etc.)

--
Phil, Squid-in-Training
 
(Pete Cresswell) <[email protected]> wrote:
> RE/
> >news:[email protected]...


> Ahhh! the coup de Grace: "WARNING: Use only specially-designed Thomson shims
> with the Thompson Stem. Standard shims will not work."


> I'm guessing that "shims" are what I call "spacers".


> What, are these guys on drugs?


http://www.lhthomson.com/stemfaq.asp

You're overthinking.

"Shims" are what adapt a 1-1/8" stem to a 1" steer tube.

BTW, I have never touched a Thomson stem, but I bet the
screws that take a 4mm hex wrench are 5mm diameter, not 4mm.