Tap chart

Tap chart typo ?

General topics, not related to any other category
Post Reply
47str8leg
Member
Posts: 124
Joined: Fri Dec 06, 2019 3:52 pm
Bikes: 41 knucklehead
57 Panhead
63 Pan
94 Dyna Wide Glide
Location: Long Island , New York
Has thanked: 2 times
Been thanked: 39 times

Tap chart

#1

Post by 47str8leg »

I’m working on putting a roller together with a wishbone frame. I was using the chart to tap all the holes clean and when I came to the coil blocks the chart called for a 3/8-24 tap but mine needed a 5/16th-18 to get the job done.

Maybe someone else can double check on there frame ?
A 3/8 bolt in that location would seem to me to be too large .

Tim
RooDog
Senior Member
Posts: 5327
Joined: Tue Oct 31, 2017 1:00 pm
Bikes: 1950 Panhead, Resto-Mod
1968 90", 5 Speed Shovelhead,
1984 Home Built Custom Evo 100" Bagger
Location: Knoxville, Tennessee
Has thanked: 2801 times
Been thanked: 2158 times

Re: Tap chart

#2

Post by RooDog »

I don't know the year model for the change, but indeed, some are 5/16, and some are 3/8. The Colony kit for the terminal box contains both sizes of double ended studs......
....RooDog....
47str8leg
Member
Posts: 124
Joined: Fri Dec 06, 2019 3:52 pm
Bikes: 41 knucklehead
57 Panhead
63 Pan
94 Dyna Wide Glide
Location: Long Island , New York
Has thanked: 2 times
Been thanked: 39 times

Re: Tap chart

#3

Post by 47str8leg »

Ok, so it has been confirmed. According to Colony manufacturing parts book all 45 and big twins from 1948-1955 have the 5/16-18 thread in the coil mount and for the big twins from 1956-1982 have a 3/8-24 thread in the coil mount.
So the start of the pan straight leg frame in 1956 was where the change was made.
I am working on a 57 project bike and a Wishbone roller at the same time and checked both. They are as per mentioned above.
So that difference should be added to the tap chart.
RooDog
Senior Member
Posts: 5327
Joined: Tue Oct 31, 2017 1:00 pm
Bikes: 1950 Panhead, Resto-Mod
1968 90", 5 Speed Shovelhead,
1984 Home Built Custom Evo 100" Bagger
Location: Knoxville, Tennessee
Has thanked: 2801 times
Been thanked: 2158 times

Re: Tap chart

#4

Post by RooDog »

Who's tap chart are we using?
panhead
Site Admin
Senior Member
Posts: 3286
Joined: Mon Jan 01, 2001 12:00 pm
Bikes: 1954 FL
Location: Holland
Has thanked: 108 times
Been thanked: 485 times

Re: Tap chart

#5

Post by panhead »

Post Reply

Return to “General topics”