16MS Crankcase studs

Information relating to the Matchless G3 or AJS Model 16 350cc Heavyweight
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BobbyG
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Joined: Wed Jan 15, 2014 5:50 pm
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16MS Crankcase studs

Post by BobbyG »

Hi All,
Would I be correct in assuming that the stud thread to crankcase is 3/8" BSW 16tpi?
Robert Gallagher
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Rob Harknett
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Re: 16MS Crankcase studs

Post by Rob Harknett »

I do not think so. What is the part number. From which the thread type can be discovered in a parts list.
Is it actually called a stud or bolt that goes through the crank case. or stud like cylinder stud of which one end screws into the crank case.
cbranni
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Re: 16MS Crankcase studs

Post by cbranni »

1955 singles have crankcase studs 5/16 dia x 26 tpi thread either end in various lengths to suit................ so spares book says under crankcase bolts, so would have nuts either side.

Best regards
Colin

http://archives.jampot.dk/book/Spares_l ... ingles.pdf
only dead fish go with the flow
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Rob Harknett
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Re: 16MS Crankcase studs

Post by Rob Harknett »

cbranni wrote:1955 singles have crankcase studs 5/16 dia x 26 tpi thread either end in various lengths to suit................ so spares book says under crankcase bolts, so would have nuts either side.

Best regards
Colin

http://archives.jampot.dk/book/Spares_l ... ingles.pdf
Crank case stud also shows dimensions in the parts book. Cylinder fits on 4 off them. Cylinder nuts go on the 26 tpi end.
cbranni
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Re: 16MS Crankcase studs

Post by cbranni »

I had wrong end of stud :D :D :D as usual
only dead fish go with the flow
Andy51
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Re: 16MS Crankcase studs

Post by Andy51 »

The roadster heavyweight longstroke singles use 3/8 BSF (20 tpi) (screws into crankcase) x 3/8 CEI (26 tpi) (takes holding down nut) studs. Cylinder head bolts are 3/8 BSW; rocker box studs are 5/16 BSW (22 tpi). Cheers, Andy
BobbyG
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Joined: Wed Jan 15, 2014 5:50 pm
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Re: 16MS Crankcase studs

Post by BobbyG »

Thank you gentlemen for your replies. The spares list, part no. 000300 says the stud is... 1 25/32in. by 3/8" (I think, the copy is unclear) by 26 and by 20 - so BSCY and BSF. I've tried a bolt in the crankcase holes, a 3/8" by 16 tpi - BSW - fits! Something is obviously amiss. The threads are not good so need helicoiling. What size kit should I go for, 3/8"BSF methinks.
Robert Gallagher
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AJS 500
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Re: 16MS Crankcase studs

Post by AJS 500 »

Yes BSF into crankcase BSCy other end...


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