Metric/Imperial Threads

vibrac

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If you are really interested in weight saving what we really need are aluminum high strength imperial nuts 1/4",5/16".3/8".1/2"
 

Pushrod Twin

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If you are really interested in weight saving what we really need are aluminum high strength imperial nuts 1/4",5/16".3/8".1/2"
That's a big ask Vibrac. Which "Imperial" threads were you anticipating, BSF, Whitworth, BsCy, UNF, UNC, Admiralty Fine, BA, oh, sorry, BA is actually Metric, my mistake.:D
 

vibrac

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BSF would do fine (Pun not intended)
:)
The Phils seemed to like them and I note so did Douglas I never know what to expect when I get to a Triumph I guess (tho I havent touched one in years) BSA are the same.Some people of oriental bike engineering bent say they often have different metric threads to EU ones so metric is not imune
 

oexing

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Yeah, I did all Brampton spindles from titanium, M 14x1 and M 12x1 with special light nuts SS, left and right hand threads. Hope these will be longlasting with IGUS plastic bushes and friction plates. But then , at 68 they will outlast me easily I guess.
Oriental metric threads are standard as in Europe except they prefer M 10 x1,25 , M 10x1,5 would be standard coarse. Hex heads on Japs are 14 mm in places, also 12mm used. Mostly you´d find 13 mm and 17 mm for M 8 and M 10, but new standard for M 10 is 16 mm now - but not widely used in home supply. But big difference to imperial grotesque designations: With metric you just get your vernier , do a quick check and know what you got. No secret files with all sizes required to find out what you deal with. Same with wire gages, get a vernier and size, like 1.2 mm and this is it to order. No need to find funny numbers of wire gages in secret files after getting some size from the vernier and finally become able to order wire according to wire numbering. Weird to see the higher the number the smaller the wire is , same with small screws. You must be British to find this logic . . . . . ;)

Vic
P1090295.JPG
 

oexing

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Or otherwise when finding difficulties while trying to get exact info about stuff this secrecy about trade knowledge may widely produce the attitude of "that´ll do . . . " - with consequences to the affected objects ?

Vic
 

Albervin

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BSF would do fine (Pun not intended)
:)
The Phils seemed to like them and I note so did Douglas I never know what to expect when I get to a Triumph I guess (tho I havent touched one in years) BSA are the same.Some people of oriental bike engineering bent say they often have different metric threads to EU ones so metric is not imune
Douglas tended to use 25 TPI in the early years because then you HAD to buy them from the factory. Very clever. I would be a big fan of Titanium spindles and fork nuts if they were available.
 

bmetcalf

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Or otherwise when finding difficulties while trying to get exact info about stuff this secrecy about trade knowledge may widely produce the attitude of "that´ll do . . . " - with consequences to the affected objects ?

Vic

True, it does result in some bodges. I have a '66 Triumph TR4A and the SU carb linkage has some BSF or BA threads, with UNF threads elsewhere on the car, and that mystifies the members on the TR4A forum I read.
 
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Mike 40M

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Late sixties, Norton and BSA, maybe some other in the group decided to go for UN threads.
So on my -70 BSAs, you have Cycle, BSF, UN and BA in different places. And some metric ones that PO have fitted. Quite a number of spanners & sockets needed. Plus the BSA affection of #3 Phillips.
The Vincent is much easier because it rarely need any spanner work.
But I've found that the Vincent K1 tool is perfect for the BSA primary plug for adding oil.
Still not found any tool for the Burman fill plug. Except a hammer and pin punch.
Old Swedish proverb translated to English:
Fitting on an English motorcycle is only dependant of size of the hammer.
 

vibrac

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Funny that the K1 is perfect for the central screw that holds Douglas rocker box covers on! My folded feeler guage set opens the burman cap. And you would be supprised how many BSF bolts are on my Jap Trail bike

NB:I was hoping someone would have replied saying "Old Bert at xxx sells high strength alloy BSF nuts" as it is I have tapped a few M8 alloy nuts 5/16 BSF for menial tasks in the past :eek:
 
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