Monobloc thread form.

[norton bob]

I have a couple of 376 monos and find that parts dont want to interchange , so i intend to use a tap and die to clear the threads on the main jet holder and block ,the thread looks like a BSP a bit smaller than 1/4 bsp but its not described in any manual , anyone know.?.

 

[Gabz]

Hi Bob , I had a look at a spare carb and it is 7/16 x 19 tpi .My thread gauge is whit. Regards , Jonathan .

 

[norton bob]

Hi Bob , I had a look at a spare carb and it is 7/16 x 19 tpi .My thread gauge is whit. Regards , Jonathan .

Thanks , I have a vast stock of taps and dies , must have that. appears to be 7/16 BSF

 

[Gabz]

Good morning , 7/16 BSF is 18tpi .Unf is 20tpi . 19tpi is non standard for that diameter . Worth a google if you can't find one. Regards ,Jonathan .

 

[L.A.B.]

It could be Special Whitworth (Whitform)...

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...although 7/16" x 19 isn't one of the "recommended" series of Whitform thread pitches according to BS 84.

 

[norton bob]

I passed a 7/16 bsf tap thro it and it took out very little and appears good ,we shall see. Moving on to looking over the one and only "Pluto " oil in frame AMC twin , still in the running in stage it appears to be a practical bike although built as Matchless it was intended to house the unit 650 Norton engine but the AMC motor and box went in much better. I took some photos ,may someday figure out how to post them. Nice to see it in my yard.

 

[Matchless]

Bob, I for one would love to see some photos of the Pluto frame if you can manage to post them.

Martyn.

 

[norton bob]

Hi Martyn, I have photos but am useless with IT stuff. Not much to see other than the fuel tank has an extra filler in the middle . The tank /seat lines could be improved in my opinion ,but the bike rides very well , has taken loads of cash to sort out some poor engine work but you should see pics soon as its going to be shown whenever possible.