Bolt size for rear of gas tank on 78E

[XS 1100 Rick]

Hi I went to remove my tank last week to do a tank flush and do a petcock rebuild and now I noticed there wasn't a bolt holding my tank securely to my frame does anyone know what size Bolt that I need. Metric yes what size I haven't got a clue. I'm sure that can find one at a Nut & Bolt Store.

Thanks Rick

[kflyboy]

I think it is an 8 mm with 12mm head. 1.25 thread space.

[XS 1100 Rick]

Would that be a course or fine thread on that .

Thanks for any replies

Rick

[natemoen]

Would that be a course or fine thread on that .

Thanks for any replies

Rick

That is a more fine thread bolt. Metric does not list as coarse or fine thread though, they list them as there actual thread pitch.

[bikerphil]

If you ask the hardware store guy for 8MM 1.25 pitch and 20MM length you should be all set. You will need a washer on that bolt also.

[skids]

I got a 13mm head on that bolt for one of the bikes (that is what I had in the bin). I highly recommend the 12mm because that wrench is more often for so many things and that would be your first guess when looking at the bolt for maintenance. Like...why the hell did they make 13mm heads????

[mack]

Lh

Ya my LH has a 13mm head on that bolt.

[XS 1100 Rick]

Thanks a lot fellas for the info.
I should have no problem getting one.

Thanks
Rick

[TomB]

The tank mount thread size is M8 x 1.25 which is standard Metric Coarse pitch for M8.

The ISO (International Standards Organisation) standard head size is 13mm AF.

However there is another metric thread standards that we as Jap Metric bike riders should be aware of, JIS (Japanese Industrial Standard) This has heads of different sizes, like the 12mm AF for M8, and 14mm AF for M10 (17mm in ISO).

Metric Coarse threads have one standard pitch for each diameter.

Metric Fine threads can have several different pitches for each diameter.

Interesting reading for insomniacs ZZZZzzzzz..... but useful info sometimes.

[XS 1100 Rick]

Thanks TomB for the info that Metric chart will be useful.


Rick

[Crusty Snippets]

Bolt

Just had mine off.
12mm wrench as stated. The washer is about one inch across to cover the rubber piece.
Unkle Crusty