Measuring neck rake

[panhead_kicker]

I have taken posession of a 64 duo frame, and would like to ensure the stock rake of the neck. The neck forging has been monkeyed with, but I was assured by the previous owner it had not been cut/raked. Both sides of the neck had been covered over with a steel plate welded on and bondo. The right side plate had been taken off, the left side was still covered when I received it. This was a long distance purchase and now that I can see things first hand, they don't look good. I have been studying the duo-glide frame blueprint here on the site, and it appears that if I measure a straight line from the rear motor mount hole center, forward 19.49 inches and then go vertical, that the center of the neck stem hole should be 30deg from that vertical. This may be tough for me to measure convincingly. I suppose a very large square will be required. Anyone else have any hints or "easier" ways to determine if the stock rake is present?

DSCN5428.JPG

speedocut.JPG

[Panacea]

Here you go, graft one of these on her http://www.raceframe.com.au/dropsaddle.html

[partshunt]

Hi: The factory drawing refers to 30 degrees from a vertical line. I found that difficult to find unless you have the factory frame jig. However, From the facrory drawing, I established where the horizontal line runs thru the frame. That was easier to find. Also, I used a 1 inch cold roll bar that takes the neck stock Timkin bearings. Using 1 inch collars, I locked the set screws for zero play in the cold roll bar/neck assembly. Then, I used an electronic drive line angle inclination meter. Using a String line and a steel plate for the meter I zeroed it on the vertical line that run from the rear to front along the frame drawing. Then I was able to read where the cold roll was and it came to 59 degrees. So, from the vertical line, my forks would be at 31 degrees. 30 degrees from a vertical line is the same as 60 degrees from a horizontal line. I think I may have tweeked it a bit to 59 degrees from Horizontal or 31 degrees from vert. This 54FL rides like a baby carriage for three years now, no wabble, no shimmy. Poor mans frame job....Joe

[PanPal]

Here you go, graft one of these on her http://www.raceframe.com.au/dropsaddle.html

Yea, that little beauty is about $450

[Panacea]

The new neck would cure the missing dampener boss as well...

[Cotten]

Although by "eyeball" the rake appears unchanged, I would encourage a complete replacement as well.

The trick to make it easy is to torch off the old headstock in such a manner that the ends of the tubes that insert into it are saved.
Then only a single easy cut of the spine will need "slugging".

If I can do it, anybody can.

....Cotten

[panhead_kicker]

If I can do it, anybody can.

HA! thats a good one Cotten. You seem to be handier than most. And better equiped. I have looked at the new neck castings though. It's worth thinking about. Or talking about. When you mentioned torching off the old casting without damaging the inserted tubes... Help me understand how the neck is put on. Are the down tubes and small overhead tube simply welded to the neck casting around their circumference where the two are seen to meet?
What I am getting at is that I had to remove the floorboard mounts. That seemed relatively simple just grinding the weld around the outside perimeter of the tab, where the tab and frame meet. The whole mount basically fell off after that. I know the neck won't simply fall off... but is a torch necessary or will a good air cutoff wheel suffice? And if the three smaller tubes can be extracted whole, why can't the spine? Is it "staked" into the casting a bit further up?

[Cotten]

PK!

A pro welder I am not.

The frame members insert a couple of inches into sockets machined within the headstock casting; Their strength depends upon this. (Members that have been sawn off must be slugged and lengthened before the headstock can be assembled, adding up to a tremendous amount of work!)

The Factory put not only a bead around each member, but holes were drilled into the casting to make windows to the members, which were then welded solid.

The old headstock can be entirely ground off, of course, if you feel dangerous with a torch. Just do not cut the tube members themselves.

The alignment gauge tubes in my photo are as suggested by the Service Manual. The horizontal one (held by an O-ring to a vertical member screwed into the tranny mount, and held against the seatpost) is used to "sweep" the rod stuck in the headstock. When its distance from the rod is perfectly even through out its entire arc, the headstock is straight up and down to the frame.
And when the original length of the inserting members has been saved, you can't get the rake wrong if you try!

As I mentioned, it only takes one real cut on the frame: the spine must be cut half-way between the seatpost and the top motor mount so that all members can be inserted simultaneously into the headstock. The spine can be slugged back together with a piece of pipe that will insert tight into the spine, slightly crushed to a "D" shape, and then welded with 'windows' as mentioned previously.

Frame work is 'tinkertoys',... and can be rewarding and fun!

....Cotten

[panhead_kicker]

Thanks for the information Cotten. I am still trying to decide whether to run this frame the way it is, fix it, or sell it. As I look down the bore of the neck from the top , the back side of the bore sticks out into the bore a bit, down about at the depth of just under where the casting accepts the frame spine. The very top of the neck , where the cup should fit, appears to not be perfectly circular, but elongated toward the back of the neck.
This is the first time I have examined a bare frame like this, so I do not know necessarily what is normal and what is not. Should the neck bore be perfectly circular all the way through? Or are these all symptoms of a rake / botched rake job?

neckbore.JPG

[partshunt]

There is no way the bearing bores should be out of round. The Timkin cups wont even start and probably crack when driven down. Altho it may be possible to recut those bearing bores, sounds like the neck has seen better days...Joe

[Cotten]

PK!

Only the counterbores for the cups need to be concentric, and in-line. The cavity between is rough forging, unless molested.

If the counterbores are egged fore and aft, it is the signature of heavy impact.

...Cotten