Plugs, Anti-Sieze, ABS and Wasting People's Time

["Tom Brown" <tbrown@xxxxxxxxxxx>]

Gary:

As Tom Cutter explained in the first reply about anti-sieze and I'll restate 
for him so he doesn't have to waste any more time on this...

Anti-Sieze makes the threads slicker.  When the threads are slicker and you 
tighten to a given torque, you're actually pulling a lot harder and putting 
more stress on the threads...as if putting near double the torque on without 
anti-seize.

Think about it.   It's an inclined plane/lever with a given amount of 
surface friction that makes a set radial resistance when the threads are 
tightened "enough".  That resistance translates into the recommended torque. 
When you take away surface friction with anti-seize, you have to tighten 
down a lot more to create the same drag (torque reading) on the wrench.

I'm not going to get into a battle of words here.  I'll just tell you that 
what TC said is true and let you figure out why if this doesn't make sense. 
He's right.

However, a lot of people don't use a torque wrench to tighten plugs.  They 
just tighten a new plug 1/4 turn past where it's "home" on the new crush 
washer around the plug.  In that case, you're not depending on a torque 
wrench reading and the 1/4 turn will still be 1/4 turn.   Same stress on the 
threads with or without the Anti-Seize, but will feel like less torque in 
your hands as you turn the wrench.  As long as you can resist the temptation 
to tighten it "a little further because it just doesn't feel tight", you're 
not over torquing....

...But then your bike's cylinder heads have threads full of anti-seize and 
will nearly forevermore have a lower friction coefficient than the clean 
threads that were in mind when the engineers decided what torque setting to 
cite for tightening your plugs.  This means anyone who uses a torque wrench 
to put plugs on your bike will be in danger of overcooking your threads.

Anti-seize is really useful stuff for many things.  I like it for coating 
the surface, lightly, between the flats on the aluminum rims and the flats 
on my rear hub (steel) to combat corrosion and galvanic reaction. (I use the 
silvery stuff that matches the wheels, not that sticky copper snot)  It does 
stop some rust.  As TC said, it's great for exhaust bolts because their so 
ripe for corrosion.

I also used it for rebuilding an old British Leyland engine from a Saab 99 
once.  It's the only thing that will prevent galvanic reaction on the head 
studs and the half iron/half aluminum block surfaces.  I don't use it on lug 
bolts unless I'm fairly sure that I'm going to be exclusively in charge of 
torque and the vehicle in question is going to be outside for extended 
periods between tire changes.  I am, in this case, very careful with my 
torque values, decreasing them about 1/3.  So far, no wheels have fallen 
off.

The case could also be made that, if the threads are corroded and rough, 
they will not tighten enough using the recommended torque.  The answer to 
that is, if the threads are corroded and rough, clean them up before you 
tighten them onto anything or you'll booger them up for sure and shorten 
their useful life immensly.

Tom Cutter is a professional mechanic who knows his stuff.  Even if he were 
not, I'd agree with him on this thread issue.  I know it to be true from 
experience and from simple physics.  He knows it to be true from repairing 
lots of stipped threads full of anti-seize.  We're lucky to have him on the 
list.   He's more than helpful.

- ----------

In the ABS situation with Bob downing his bike to save a bicyclist from 
serious harm, all he's saying is that, while ABS helps you stop faster in an 
emergency, it's limiting in other ways.   I think we can all agree on that.

ABS IS a little bit limiting.   Sliding the bike on purpose, for instance, 
isn't practical anymore.   Sometimes, when you hit a bump in the road while 
stopping for a light, there's this helpless feeling while the ABS kicks the 
braking out and hasn't got its bearings back.   It's a good thing for most 
street situations, especially emergency situations, but it's not perfect and 
has some minor costs in feel for non-emergency riding.   Anyone who's used 
it knows this.

If I had a bike with BMWs first ABS system, I might consider taking it out. 
It's really slow and can cause as much trouble as it saves.  I'm not 
completely convinced it's worth keeping on the old bikes.

- -TB

3rd BMW bike with ABS, 2nd with servo ABS,
100K+ combined miles on 3 Oilhead RTs.
'00 Aprilia Mille R with Excellent non-ABS brakes.
Have nice garage, have owned and worked on numerous BMW cars and bikes since 
1976, run a tool and die/metal stamping business, know a thing or two about 
tools, threads and fixing stuff, am not a professional BMW mechanic, but 
still do a lot of my own work on my bikes and cars.  I'm not a mechanic-god, 
but I know what I'm talking about here.

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