M8 thread pitch on honda motorcycles.

Anyone know the thread pitch on Honda M8 bolts?

Thanks in advance.

 

If you have a metric bolt, just lay a metric scale next to it.

1.0mm is a very common pitch.

Typical pitches are 0.5mm, 0.75mm, 1.0mm, 1.25mm and 1.5mm, from one
thread crest to the next.

 

If you have a metric bolt, just lay a metric scale next to it.

1.0mm is a very common pitch.

 

So the thread spacing of a 1.0mm bolt is 0.0394 inches and the thread
spacing on a 1.25mm bolt is 0.0493 inches.

That's a *very noticeable* difference in thread pitch.

You do have a caliper or a steel scale, don't you?

 

Well, metric coarse M8 is 1.25, metric fine M8 is 1.0. I'd expect
Honda to use fine on engine parts, but that's just an edjumificated guess...
This is where calipers, thread gauges, or plain rulers cumin handy -- assuming
you've got a sample to test, of course. :-/

--
Ivan Reid, School of Engineering & Design, _____________ CMS Collaboration,
Brunel University. Ivan.Reid@[brunel.ac.uk|cern.ch] Room 40-1-B12, CERN
GSX600F, RG250WD "You Porsche. Me pass!" DoD #484 JKLO#003, 005
WP7# 3000 LC Unit #2368 (tinlc) UKMC#00009 BOTAFOT#16 UKRMMA#7 (Hon)
KotPT -- "for stupidity above and beyond the call of duty".

 

Sure is. About the width of four human hairs.

 

He's not answering the question because he doesn't know.

 

That would be my guess too, but I need to be sure before ordering a V-coil
thread repair kit and refill inset pack from a seller who has a £50 minimum
order .

 

Honda *does not* give the thread pitch on their parts fiches, they
just call out the bolt diameter in millimeters, followed by the
length, again in millimeters.

So, you'll need to actually *measure* the thread pitch with an
appropriate gauge or caliper before ordering any parts.

 

Printable metric bolt gauge:

http://tinyurl.com/dkznex

http://www.boltdepot.com/Fastener-Information/Printable-Tools/Metric-Hex-Bolt-Sizes.pdf

 

Why are you trying to start an argument? Look back to the posting before
Ian's, and you'll see that this was *precisely* the advice that Ian was
referring to.

Advice given by Ivan, who you already seem to have a downer on since he
gently rubbed your face in it with your guff about magnets.

Ian actually quoted it, but you snipped it, and started trying to come
over all self-important with "advice".

Enquiring minds need to ask: why did you snip advice that had been
given, and then re-post it?

 

The CB900 I'm in the process of TOGing out uses M10 Fine on the engine
mounts[1] so I'd assume the M8s are Fine as well.

I know making assumptions is risky but my tub of stainless fasteners are
M8 fine and they fit the bolts from the CB900. Of course, that may just
mean a DPO had used M8 fine bolts instead of M8 coarse but I'd think
not.

Bob

[1] So I've transplanted a couple of them to the Laverda - same size,
same thread, less rusty.

 

Why are *you* trying to start an argument?

Is arguing what you live for?

 

Using a different thread pitch on *through bolts* isn't an important
issue, but when
an amateur mechanic tries to screw a 1.25 pitch bolt into a 1.00 pitch
blind hole in an aluminum casting, the first threads will get stripped
out.

 

I'm not trying to start an argument. I asked a question.

And that was: perfectly good advice was given, quoted, and then you
snipped it out and repeated it ab initio, as if it was the first time it
had been suggested.

Why???

(You need to lessen your paranoia, you sad unfulfilled person)

 

Er, yes, which is presumably one reason why the question was asked
originally. Your point?

 

Beg to differ. Motorcycle workshop manuals are full of tables of
tightening torques for all sorts of screw fasteners. Using the right
torque on the wrong pitch can lead either to under-tightened fasteners
or stripped threads.

--
Ivan Reid, School of Engineering & Design, _____________ CMS Collaboration,
Brunel University. Ivan.Reid@[brunel.ac.uk|cern.ch] Room 40-1-B12, CERN
GSX600F, RG250WD "You Porsche. Me pass!" DoD #484 JKLO#003, 005
WP7# 3000 LC Unit #2368 (tinlc) UKMC#00009 BOTAFOT#16 UKRMMA#7 (Hon)
KotPT -- "for stupidity above and beyond the call of duty".

 

Bob Scott wrote:
....

Interesting that the M8's would be Fine pitch. Honda Common Service Manual circa 1993 gives 'typical' ISO threads found on Honda vehicles with the M8 at 1.25 mm pitch. I'm curious which parts have 1.0 mm pitch threads.

 

The banjo bolts in the brake system *might* have 10mm diameter 1.0mm
pitch threads or 1.25mm pitch threads, and trying to substitute the
wrong thread can be expen$ive.

 

That you're a Genuine Pain in the Ass.