CBH springer top tree fab dimension question

[DKillam]

The top tree plan view (sheet SF1.1) shows the outline of the large dust shield and the 1.250" bore thru for the steering stem (section D-D), but doesn't show dimensions for the counterbore that allows the bearing adjuster nut, lock washer and bearing lock nut. This scales out to about 1 15/16" dia. x 1/2" deep (on sheet SF1.8 - Typical Steering Neck Assembly).

Can anyone verify this dimension for the counterbore before I start cutting?

Top tree counterbore.JPG (35.04 KiB) Viewed 4785 times

[DKillam]

Too late - counterbored to 2" dia. x 1/2" deep (measured from bottom of tree).

Top tree counterbore3.JPG (56.81 KiB) Viewed 4778 times

Top tree counterbore2.JPG (35.69 KiB) Viewed 4778 times

[curt]

i didnt do a counter bore when i did mine i drilled the 1 1/4 hole that slid over the shoulder on the nut then tightend everything up on the bike with the wheel and spacers before welding the lower tree to the rear legs . i did counter bore the top tree for the rear legs 1/2 inch . nice work there by the way

[DKillam]

i didnt do a counter bore when i did mine i drilled the 1 1/4 hole that slid over the shoulder on the nut then tightend everything up on the bike with the wheel and spacers before welding the lower tree to the rear legs . i did counter bore the top tree for the rear legs 1/2 inch . nice work there by the way

Curt,
Do you have a pic of your stem and upper tree assembly that you described? Also, did you weld the bottom of the stem to the lower tree, or did you use a nut? If so, did you use the lower nut to adjust the bearing preload?
Sorry for the dumb questions - I'm having a tough time visualizing the full assembly.

[curt]

viewtopic.php?f=34&t=9
i welded the stem to the bottom tree . the top nut sets the bearing preload and the top tree sits on the rear legs and the shoulder of the nut with just enough pressure to keep the top nut from moving and keeping the tree from twisting . thats why i waited to weld the rear legs until i everything torqued in place on the frame and sure it was strait . i dont have the pics in my computer anymore but this link should take you to my build all the pics i had are there hope it helps . and ask as many questions as you like i will try to help i am no expert i ask lots of questions myself

[DKillam]

viewtopic.php?f=34&t=9
i welded the stem to the bottom tree . the top nut sets the bearing preload and the top tree sits on the rear legs and the shoulder of the nut with just enough pressure to keep the top nut from moving and keeping the tree from twisting . thats why i waited to weld the rear legs until i everything torqued in place on the frame and sure it was strait . i dont have the pics in my computer anymore but this link should take you to my build all the pics i had are there hope it helps . and ask as many questions as you like i will try to help i am no expert i ask lots of questions myself

Curt,
I appreciate the reply and the link to your build - helps a lot! I'm almost through machining the trees. The stem is complete and the neck will be here today (ordered from Bitter End Old School Choppers). I'm modifying a Paughco hardtail frame(increasing the rake to 40~45 degrees), so I have to do that before my mockup can start. How much rake did you end up with on your build?
Thanks for the info!
Don

[curt]

i also used bitter end neck on that build it ended up at 44 degrees i think the heat from welding changed it it was 45 but that neck was thick and took some good heat from the tig welder .

[curt]

you should do a build thread id love to see it and im sure others would chime in and help along the way

[DKillam]

you should do a build thread id love to see it and im sure others would chime in and help along the way

I've been thinking about a build thread. I'm doing one on shovelhead.us board - that's where I went to the dark side, after this site crashed several years ago. Dan's a member there, as well.
I'll have to resize a lot of pics, but that's OK. Give me a few days to get my stuff together and I'll start a new thread.
Don

[curt]

cool

[Fossil]

The bearing preload nut and locknut go under the top tree so no counterbore needed. Most of the assorted nuts have a 1.25" o.d. collar to they seat inside the 1.25" thru-bore. I think we covered this on the main site in the steering neck section on frame or fork fabrication.

[DKillam]

The bearing preload nut and locknut go under the top tree so no counterbore needed. Most of the assorted nuts have a 1.25" o.d. collar to they seat inside the 1.25" thru-bore. I think we covered this on the main site in the steering neck section on frame or fork fabrication.

I can't figure out how I got it wrong, but the stem lock nut and jam nut needed to go up into the top tree so I'd have enough threads for the cap nut to attach to the stem. I'll reassemble the trees and take a pic so you can see what it looks like.

I have another question - this time rocker geometry. I'll start another thread on that subject.