Thread size

[rovert57]

The thread on one of the mounting points on the rocker cover feels like it might give me some problems so could I asl what is the pitch size of the tread ,I know it’s a 6 mm x 20 but the size of the thread is not listed and I was thinking of buying a tap and die set just to clean the thread up in the hole .
Thanks for any info in advance .

 

[SBD]

M6 preferred thread pitch is 1mm. You’ll generally struggle to buy the non-preferred sizes.

Tracy tools in Dartmouth are a good source of taps, dies, etc. (and they have the non standard sizes too)

https://www.tracytools.com/product/6-x-1-metric-roll-tap/

 

[rovert57]

So would it be safe to assume that most of the smaller bolts would also be of 1mm pitch.
Thanks for the quick response.

 

[Hann]

If you can see well enough (!) you can do what i often do - count the distance of ten thread `crests` with an engineers rule and divide by 10.
eg: 10mm - 1.0mm pitch, 12.5mm - 1.25mm pitch etc.

 

[dicktheleg]

Or get a known m6 x 1 and lay it along the bolt, it’ll match up if it’s the same.

 

[DrFarkoff]

Or get a known m6 x 1 and lay it along the bolt, it’ll match up if it’s the same.

What bike would be a great Clue to be honest

If an Airhead (as in the true version) ??? M6 x 1

Plus what E says above

 

[john1961]

run a m6 nut down the thread,

 

[INBOC]

Hann,s tip is a good one, also the hole size is a good clue specifically for metric threads, this can sometimes help decide if it’s metric fine which some threads are on vehicles. The basic premise of Metric threads is the outer diameter of bolt minus the hole = the pitch. So a 6mm diameter bolt minus a 5mm hole = 1mm pitch.
Metric fine M6 is a 6mm bolt but a drilled hole of 5.2mm because the pitch is 0.75mm.There are charts online to help with metric threads. Imperial a whole box of frogs .

 

[SBD]

So would it be safe to assume that most of the smaller bolts would also be of 1mm pitch.
Thanks for the quick response.

No. That would be an entirely bad assumption. They are not.

Basic Metric Thread Chart (M1 – M100) : Fuller Fasteners

Fuller Fasteners, Distributor of Metric and Imperial Fasteners, stainless steel, brass, nylon, hex nuts, bolts, nuts, screws, taps, dies, tools and kn95 masks

fullerfasteners.com

The pitch changes with the diameter, and whether it’s coarse or fine or non-preferred.

Measure the diameter with a digital (vernier) caliper, a tenner in Lidl or on Amazon.

For the pitch, Hann has summed it up, but measuring pitches on the actual screw is difficult. Roll the screw on a piece of paper at the edge of a table, and then measure the pitch on the paper, it’s easier.

 

[Oldrat]

I use a thread pitch guage. Easy to use, cheap to buy.

Link

 

[SBD]

I use a thread pitch guage. Easy to use, cheap to buy.

Link

View attachment 439302

Agree, but if he doesn’t have one, a piece of paper (and a ruler) works tonight!

 

[captaindan]

The thread on one of the mounting points on the rocker cover feels like it might give me some problems so could I asl what is the pitch size of the tread ,I know it’s a 6 mm x 20 but the size of the thread is not listed and I was thinking of buying a tap and die set just to clean the thread up in the hole .
Thanks for any info in advance .

If you can get to Wigan ( home ) or Burnley ( office ) I have an m6 x 1 tap and a thread gauge. Happy to help.
Dan

 

[rovert57]

If you can get to Wigan ( home ) or Burnley ( office ) I have an m6 x 1 tap and a thread gauge. Happy to help.
Dan

Thanks Dan
I’ve put the guard’s back on and the thread didn’t seem to be binding so I’ll leave it for now but thanks for the offer and information to all on here .

 

[snelly]

I've had this years; it's good enough for a quick guesstimate;

If you can see well enough (!) you can do what i often do - count the distance of ten thread `crests` with an engineers rule and divide by 10.
eg: 10mm - 1.0mm pitch, 12.5mm - 1.25mm pitch etc.

I have had this for years; it's good for a quick guide.

 

[Santa-2512]

If its mothership it wont be std,

it will be something like M6 x20.25 ,,

as they say, close , but no cigar

Why dont you have a look on real oem, they normally list all the thread and pitch stuff

 

[Tinytim]

If you can get to Wigan ( home ) or Burnley ( office ) I have an m6 x 1 tap and a thread gauge. Happy to help.
Dan

Deja vu....fekk me Trev, have you still not bought yourself a tap and die set you tight twat. I thought you might have done by now after I loaned you one about 15 years ago and which you returned when finished with.

 

[DrFarkoff]

If its mothership it wont be std,

it will be something like M6 x20.25 ,,

as they say, close , but no cigar

Why dont you have a look on real oem, they normally list all the thread and pitch stuff

I think he is asking about the two studs in the actual rocker cover that push through the cylinder heads and are affixed with nuts and washers

Which may have been helpful to have had a clearer description

Anyway if that is the required thread pitch ? Then it is M6 x 1

 

[rovert57]

Deja vu....fekk me Trev, have you still not bought yourself a tap and die set you tight twat. I thought you might have done by now after I loaned you one about 15 years ago and which you returned when finished with.

Yes Tim ,I remember you loaning me one for the damaged thread on my blackbirds fork .do you still have a blackbird .

 

[Captain jack]

Fwiw. Thread size on mirrors is 10 x 1.5 whereas it is 1.25 pitch on almost all other non bmw bikes

 

[Tinytim]

Yes Tim ,I remember you loaning me one for the damaged thread on my blackbirds fork .do you still have a blackbird .

LOL. Yes mate. Did have 3 ffs's but now down to 2. Just can't grow up