FT: Frame (Twin) Bold Machine Co Shocks

vibrac

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Now lets test the internet, "whats the spring poundage and dimensions of a 1939 Nash valve spring":rolleyes:
 

timetraveller

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I don't know the answer to that question but lots of valve springs I have checked have been in the range of 100 to 200 lbs/inch. Let us take the 100 lbs/inch figure for a starter. Suppose that with the rider only on the seat the springs are compressed about half an inch. Two springs give a total resistance of 100 lbs. Now put a 100 lbs pillion passenger on and the springs have to compress another half an inch. Or suppose that the pillion passenger is a sturdy 200 lbs chap and they will now be compressed a total of 1.5" each, Go over a serious bump and we might expect a further half inch of compression. So a range of 2" might be required and that will result in the seat pivoting backward. Only those who have used such a system can tell us whether they were happy with it in all circumstances. My feeling is that for those who always ride alone it might be OK For those who take the occasional bulky person on the back there might be problems. One of the above writers said that his wife liked it. Without being personal, is she at the lower or upper end of the weight range?
The bike I rode when I first left home in 1956 was a Triumph 3T, a 350 twin with a solid rear end. One of my first things to change on the bike was to fit a dual seat which had springs under the rear of it. This replaced the original sprung saddle and rear passenger squab and gave any pillion passenger a much more comfortable ride.
 

Michael Vane-Hunt

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1939 Nash valve spring
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specs.
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Gene Nehring

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So I thought I would give a follow up to this thread. I have made contact with Albert Bold a master engineer, his father was friends with Gene Aucott and together (Gene and Albert's father)they made the original Aucott shocks. Gene was a close friend of the Bold family and Albert has many fond memories of Gene.

Albert has not worked in the family business for many years and was not sure if any of the original patterns or parts would remain. He made a call to his cousin who still runs the family business and they have found a number of original parts. Albert has asked me to canvas the Club to see if people would be interested in the shocks again.

So is there any one else who might be interested in a set? I am still working out the details with Albert at the moment.

As a side note Albert is currently restoring the Jim Redman / Mike Hailwood 6 cylinder honda and has a number of MV Augustas.
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