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

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.

Understood that there's some sort of engineering manual somewhere that says for
such-and-so a load, 4mm is sufficient.

But geeze!....knowing that 5mm fits just about everything else - including a
subassembly on the very part in question....and 5mm would definately carry the
load...what kind of mentality would use 4mm? They do the same thing on their
seatposts. The *world* uses 5mm, but do they? Nooooo, it's gotta be 4mm.
What is it with these guys? Some kind of engineer thing?

That's the rant part...

The question (I think I already know what the answer is going to be...but what
the heck?): is there any such thing as 4mm bolts that take a 5mm key so I can
get back on the Good-Right-And-Holy path of as few tools needed as possible for
adjustments in the field?
--
PeteCresswell

Oops...some genius has used 4mm screws on the Thompson stem's clamp.

Understood that there's some sort of engineering manual somewhere that
says for such-and-so a load, 4mm is sufficient.

But geeze!....knowing that 5mm fits just about everything else - including
a subassembly on the very part in question....and 5mm would definately
carry the
load...what kind of mentality would use 4mm? They do the same thing on
their
seatposts. The *world* uses 5mm, but do they? Nooooo, it's gotta be
4mm.
What is it with these guys? Some kind of engineer thing?

That's the rant part...

The question (I think I already know what the answer is going to be...but
what the heck?): is there any such thing as 4mm bolts that take a 5mm key
so I can get back on the Good-Right-And-Holy path of as few tools needed
as possible for adjustments in the field?

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.

As far as your question, I would hazard a guess that: NO, they don't make
4mm bolts that have a 5mm head. Even if they do, it seems unlikely the
head would fit into the bored holes in the face plate.

John M ...I like their seat posts though.

PS, doesn't your multi tool have both a 4mm and a 5mm in it?

(Pete Cresswell) wrote:
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.

Understood that there's some sort of engineering manual somewhere
that says for such-and-so a load, 4mm is sufficient.

But geeze!....knowing that 5mm fits just about everything else -
including a subassembly on the very part in question....and 5mm would
definately carry the load...what kind of mentality would use 4mm?
They do the same thing on their seatposts. The *world* uses 5mm,
but do they? Nooooo, it's gotta be 4mm. What is it with these guys?
Some kind of engineer thing?

That's the rant part...

The question (I think I already know what the answer is going to
be...but what the heck?): is there any such thing as 4mm bolts that
take a 5mm key so I can get back on the Good-Right-And-Holy path of
as few tools needed as possible for adjustments in the field?

Suck it up and carry a 4-mm; most multi-tools have one, anyway.

Bill "new FSA carbon seatpost (roadie) also uses 4s" S.

"(Pete Cresswell)" wrote in message
...
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".



Should've bought a real Thomson stem. They still use 4mm hex bolts but
they're made a hell of a lot better than those cheap Thompson knockoffs!!!
;^p''''

But seriously, suck it up like Sorni said and carry a 4mm. Also make sure
the steerer and the inside of the stem are completely clean and free from
any grease contamination. Then grease the threads on the bolts in the clamp
and put a little grease under the head. Those little suckers bind over time
if put in dry and you'll have to drill 'em out to get the stem off. Take
turns tighening each one until the torque needed is reached. The reverse is
true when removing if a bolt gets tight go back and snug the opposite one a
bit to free it.

Enjoy the stem, they really are the best.

Mike

Pete Cresswell says:

is there any such thing as 4mm bolts that take a 5mm key

No, but if you grind/file the other end of your 5mm key down to 4mm, you'll be
all set (and it will be lighter, too...)

Steve ;-)

"(Pete Cresswell)" wrote in message
...

The question (I think I already know what the answer is going to be...but
what
the heck?): is there any such thing as 4mm bolts that take a 5mm key so I
can
get back on the Good-Right-And-Holy path of as few tools needed as
possible for
adjustments in the field?
--
PeteCresswell

Yeah.....those 4mm Allen keys sure are heavy... :-p

RE/
But seriously, suck it up like Sorni said and carry a 4mm. Also make sure
the steerer and the inside of the stem are completely clean and free from
any grease contamination. Then grease the threads on the bolts in the clamp
and put a little grease under the head. Those little suckers bind over time
if put in dry and you'll have to drill 'em out to get the stem off. Take
turns tighening each one until the torque needed is reached. The reverse is
true when removing if a bolt gets tight go back and snug the opposite one a
bit to free it.

Enjoy the stem, they really are the best.

I carry all that stuff in the form of a Crand Bro's multi-tool...it was more the
principle of the thing...like the cars where they place the oil filter so you
have go be a controtionist to change it...or the oil fill thingie where you have
to hold the oil can out at arm's lengh to fill it...

OTOH, this stem gives new meaning to the word "solid"....

How come there shouldn't be grease on the steerer tube?
--
PeteCresswell

RE/
Yeah.....those 4mm Allen keys sure are heavy...

But if you're in the field, there's a diff between having to fiddle with two
tools and just one. Maybe not a huge diff, but it's still two things to
retrieve from the saddle pack, two things to replace, and two things to avoid
dropping in the grass while fooling around with the stem and simultaneously
holding both tools, the cap screw, and the spacers in one hand. I was more
questioning the mentality of a designer that ignores all that than complaining
about an extra allen key - which I have anyhow.

Too much coffee again, I guess.
--
PeteCresswell

"(Pete Cresswell)" wrote in message
...
RE/
But seriously, suck it up like Sorni said and carry a 4mm. Also make
sure
the steerer and the inside of the stem are completely clean and free from
any grease contamination. Then grease the threads on the bolts in the
clamp
and put a little grease under the head. Those little suckers bind over
time
if put in dry and you'll have to drill 'em out to get the stem off. Take
turns tighening each one until the torque needed is reached. The reverse
is
true when removing if a bolt gets tight go back and snug the opposite one
a
bit to free it.

Enjoy the stem, they really are the best.

I carry all that stuff in the form of a Crand Bro's multi-tool...it was
more the
principle of the thing...like the cars where they place the oil filter so
you
have go be a controtionist to change it...or the oil fill thingie where
you have
to hold the oil can out at arm's lengh to fill it...

I know, but if you look at the clamp pieces there isn't much room for bigger
bolts. I guess they decided on giving you more material for strength rather
than bigger bolts for convienence.

OTOH, this stem gives new meaning to the word "solid"....

How come there shouldn't be grease on the steerer tube?

I had trouble with mine slipping after installing my new fork. Apparently I
got some grease on it when I passed it through the headset. I cleaned it
off and no more slipping. That,and it says to do so in Step 4.
http://www.lhthomson.com/docs/stem_instr.pdf . ;^) The clamp relies more
on friction than constricting force to hold the steerer.

Mike

"(Pete Cresswell)" wrote in message
...
I was more
questioning the mentality of a designer that ignores all that than
complaining
about an extra allen key - which I have anyhow.

--
PeteCresswell


I know, I know.... I was just being sarcastic. Sarcasm....the lowest form
of humour. You're spot on about having to be a contortionist to remove oil
filters. Especially on Japanese cars. Maybe it's the Japs revenge for
Hiroshima? :-)