What bolt is this? CL77 Steering Stem

peter4821 · Post by **peter4821** » Fri Mar 14, 2014 6:28 am

ok then what is the pitch on case and cover screws? Keep it light ......

G-Man · Post by **G-Man** » Fri Mar 14, 2014 9:55 am

M6 x 1.0 on the cases. Other screws and bolts vary in pitch depending upon the year of manufacture as Honda changed from JIS (Japanese Industry Standard) to ISO Metric which have slightly different pitches.

thread size- newISO - oldJIS
3mm- .5 .6
4mm- .7 .75
5mm- .8 .9
6mm- 1.0 1.0
8mm- 1.25 1.0
10mm- 1.5 1.25
12mm- 1.75 1.5

Not all of these are used on Hondas but you'll see that only M6 has stayed the same.

So - not all 1.25 by a long way

G

Spitfire151 · Post by **Spitfire151** » Sat Mar 15, 2014 11:32 am

Wow thanks Hoosier and G-man, did you glean that info from trial and error or is it published somewhere? I have a Clymer's and an original manual but this makes me hopeful I don't discover any more bolts missing/needing replaced.

Hoosier Tom · Post by **Hoosier Tom** » Sat Mar 15, 2014 12:09 pm

Spitfire,

G gave a nice write up on the sizes. I am sure there are published references that I am not aware of but do know it is published in Bill Silver's manuals and discussed several times on the forum over the years. If you do a search for JIS, thread pitch, etc you will find the info.

HT

Spitfire151 · Post by **Spitfire151** » Sat Mar 15, 2014 12:11 pm

Next on my list to buy, thanks Hoosier

G-Man · Post by **G-Man** » Sat Mar 15, 2014 2:43 pm

You have to be careful as even JIS changed over the years. The Italians and Germans use a variety of different thread pitches on metric bolts when it suits them. Buy a thread pitch gauge to be sure. Otherwise, just count the threads over a 10mm length and divide by 10.... :-)

G

Spitfire151 · Post by **Spitfire151** » Sun Mar 16, 2014 5:46 pm

Good to know, thanks again!