How do I determine thread pitch?

[Motorider]

I need to chase the threads on the Valk, where the 10mm X 70mm bolt behind the saddlebags screws into. The bolt is number 45 on the parts diagram for saddlebags. I looked online to buy a tap and found there are three different pitches listed. They are 1.00 1.25 and 1.50. Anyone know which pitch I need?

[sugerbear]

1.25 is standard i think. if ya have a home depot near they have a tool for checking.
sorry couldn't be of more help.

[Madmike]

There is a "tool" called a thread pitch gauge that you use to determine thread pitch (one way).  Here is a link to one that has a half decent picture.

http://www.sears.com/shc/s/p_10153_12605_00952316000P?vName=Tools&cName=HandTools,GeneralPurpose&sName=Bolt-Out,%20Taps%20&%20Dies&psid=NEXTAG01&sid=IDx20070921x00003j


Do you have the bolt that came out of the hole??  If so take it to the store with you and you can lay a tap or another bolt along the threads and get the one that matches the best. You will likely need to replace the bolt or at chase the threads depending how much damage there is to them.

Here is a link as an example

http://www.thesitebox.com/Category/4608/die-nut-metric.aspx

They are handy as you can turn them with a wrench or socket.  In addition to tap and die sets I have sets in metric and standard threads in my toolbox.  They are handy for quick rethreading.  You can typically find them in auto supply stores on the turn racks out front.  I think some of the ones that I have were packaged by Hastings.

Sorry I can't be more specific for the bolt in question but hopefully these tools will help in the future.

[DFragn]

I need to chase the threads on the Valk, where the 10mm X 70mm bolt behind the saddlebags screws into. The bolt is number 45 on the parts diagram for saddlebags. I looked online to buy a tap and found there are three different pitches listed. They are 1.00 1.25 and 1.50. Anyone know which pitch I need?

Honda's parts fiche doesn't give thread pitch nor does the Service manual.
Next time your out & about just swing by your local hardware store and spin a M10-1.00/1.25/1.50 nut on your bolt ( or identical 1 from other side or same side) after you know which nut spins then hit the next aisle over and buy the tap for 6 or 7 bucks.
Unless of course you live 100 miles from no where then someone would need to be more help then me!

[Thunderbolt]

Which makes it hard to find.  Most places you will find 1.00 and 1.50. 

[Airetime]

I need to chase the threads on the Valk, where the 10mm X 70mm bolt behind the saddlebags screws into. The bolt is number 45 on the parts diagram for saddlebags. I looked online to buy a tap and found there are three different pitches listed. They are 1.00 1.25 and 1.50. Anyone know which pitch I need?

Go to this link http://www.boltdepot.com/Fastener-Information/Printable-Tools/Default.aspx and use their Layover chart for metric and you can take the guesswork out of what you have. You can also take a bolt with you to the hardware store.

[Motorider]

Thanks to everyone for their input, I will try your ideas until I find the correct tap.

[Grandpot]

Motorider:

The numbers, 1.00, 1.25, 1.50 for metric screws refers the distance between the crest (top) of one thread to another in milimeters.  Using a metric tape measure or ruler, measure from across the crests.  Usually, one millimeter will be the distance between the small divisions on the tape measure and it is difficult to see the divisions, so do the following:

Over a distance of one centimeter (10 milimeters), count the number of crests and divide that into 10.  If there are 10, then the pitch is 1.00.  If there are eight, then the pitch is 1.25.  If there are about 6 1/2, then the pitch is 1.50.

[chrise2469]

In this case the thread pitch is 10mmx1.25.   Both the 8mm and 10mm bolts are 1.25 pitch.

I know this because I've been trying to find a 95mm in that pitch bolt for my trailer hitch locally and its darn near impossible.  The bolt supply houses only have 1.50 pitch, which is US standard size. The 1.25  pitch is JIS (japanese industrial standard).

The tap should be available locally. It came in my canadian tire tap set.

Good luck.