TRIUMPH GT-6
 

 

Triumph fastener part number system
(Information courtesy of John Kipping)

Part numbers for nuts, bolts, & washers use Triumph's system indicating the size & type, shown in the chart below.

A nut with part # YN2912 is a 9/16" UNF nyloc nut.
A bolt with part # KT504 is a No. 10 UNF, countersunk slotted screw, 1/2" in length.
A washer with part # WL0208 is a split-ring lockwasher.

Nuts   Bolts
Two-letter prefix gives type of nut.
Thread size is indicated by the last two digits. 		  Two-letter prefix gives type of bolt.
Length of bolt is indicated by the last two digits, in eighths of an inch (up to 49).
Thread type is always UNF unless the second digit from the right is 5, in which case the thread will be UNC.
Thread size is indicated by the first digit(s)
(This digit may or may not be preceded by a 0, but the table below shows leading zeroes for reference.)
PrefixType of nut   PrefixType of bolt
HNplain nut   HUsetscrew (threaded all the way to the head)
YNnyloc nut   HBbolt
JNjam nut (i.e., half-thickness)   KXcountersunk crosshead
TNthin type nyloc   PTpan head slotted
    PXpan head crosshead
Last 2 digitsThread size   First digit(s)Thread size
03No. 6 UNF   03No. 6 UNF
04No. 8 UNF   04No. 8 UNF
05No. 10 UNF   05No. 10 UNF
071/4 UNF   071/4 UNF
085/16 UNF   085/16 UNF
093/8 UNF   093/8 UNF
107/16 UNF   107/16 UNF
111/2 UNF   111/2 UNF
129/16 UNF   129/16 UNF
135/8 UNF   135/8 UNF
53No. 6 UNC   53No. 6 UNC
571/4 UNC   571/4 UNC

Washers
Prefix gives type of washer:
PrefixType of washer
WPplain washer
WLlock washer (split-ring type)
WNshakeproof washer (toothed type)

TRIUMPH GT-6
 
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