- Thread starter badabec
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Are they common to any other Citroen's?
Agroshield
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Turn the bar down to 9mm diameter using a drill press and file. If you wanted them to look a little closer the full length, 3/8" diameter raw material could be a good starting point, and less to file off.
badabec
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Hello, thanks for all the input. It is a 1972 DS, main bolt sizes are M5, M7 and M9. Early DS used M5 0.7 pitch!
My plan was to reduce 10mm bar in diameter in the lathe.
Should I reduce to exactly 9mm or go a bit further to make life easier for the tap?
Would 8.8mm be too far?
Knowing my machining abilities, it will be undersize anyway.
My plan was to reduce 10mm bar in diameter in the lathe.
Should I reduce to exactly 9mm or go a bit further to make life easier for the tap?
Would 8.8mm be too far?
Knowing my machining abilities, it will be undersize anyway.
Nomad
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- North Devon (for how long?)
Do you have any local motorcycle workshops?
I needed a couple of odd M7 studs & nuts and my local bike shop had the spares in stock - I think they were common on some Italian bike engines in the past.
If they stock M7 they might also have M9 ? It's worth a visit ...
I needed a couple of odd M7 studs & nuts and my local bike shop had the spares in stock - I think they were common on some Italian bike engines in the past.
If they stock M7 they might also have M9 ? It's worth a visit ...
Seadog
Save the planet. It's the only one with rum!
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M7 is used on some Piaggio scooters for the exhaust flange. I bought some from Ebay last year.
Misterg
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Assuming they follow the ISO standard:
Thread depth is 0.54 x pitch, so 0.677 mm. Last 1/8th of thread depth on a male thread is truncated, so make the blank 9-(.677/8 x2) = 8.83mm (ish) diameter
Agroshield
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Cutting a male thread with a tap will never be easy no matter what the diameter, sorry.
Please look at diagram here:
ISO metric screw thread - Wikipedia
D maj = D so 9mm is the top of the flat on the thread, not the projected top of a sharp v-thread.
Misterg
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Nomad
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It might be an Italian standard - mine were replacement exhaust studs for a Minarelli / Malaguti kids bike.
MattF
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9mm.
When you're reducing the rod, just reduce the first 5mm or so, initially. That gives you a measuring point for the caliper, & a guide to to turn the remainder down to.
zzr1200
Working at 650 ft on open steel work.
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9mm x 1.25 50mm long or 80mm from the drop down.....Tis a shame XR's went to the wall...
Mick Annick
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Have you looked over here? I can ship / bring them over for you
Wallace
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Thanks for typing all that out Pete, l was just about to including Tracey Tools!
I have a 9x1mm tap and die bought from Tracey Tools when they were in Kingston, plus 7x1mm, 8x1mm and 10x1mm. I was 10 years old and my father let me spend my pocket money on them, the old bugger didn't check the pitches on what l bought and laughed later. I have used all of them in the past 50 years.
