Cranbrook Springer Forked BTR YD100 Replica Build (without fabrication)

GoldenMotor.com

indian22

Well-Known Member
Dec 31, 2014
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I think your leaf fork looks great. If you want to read up on fork geometry in one thread I'd recommend The Veskt V-twin build where great forum members persuaded him to re work his fork and why. Long read but worth it if you really want to understand why and they just touched on the high points. If you ever plan to ride fast on anything with two wheels it's a good idea to study up it could save your life. At bike speeds it matters a bit but faster velocity it really is exponential!
 

indian22

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Dec 31, 2014
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Hey Danny just wanted to add that you have received a lot of great info from the forum members which have responded & I don't want to sound as if they gave you bad advice at all. I've found the comments and suggestions very good, but I know you like to read good posts from solid builders and Lurker's posts are good stuff because he was a newbie that tackled two tough project build back to back with basic hand tools and a plan, but he knew when to take solid advice and that spoke well of him.

Sometimes my posts come off as being harsh & and that's not at all my intent.

Rick C.
 

Nightster

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Mar 3, 2021
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Not harsh at all Rick, and thanks for all the kind compliments..

I will definitely Read that information and further educate myself. Thanks for the tip.

I find people like yourself, Curtis, Tom, Steve, Pete and A few others That don’t know their names, very helpful and patient with me. I sometimes post a question on here or start to post a question on here and then just start thinking for myself and doing more research. Most of the time I can find the answer, but the knowledge here is invaluable !!!!

Unfortunately I’m pretty bullheaded and set in my ways as I expect most of the cool guys on this site are lol. I am definitely not opposed to anyone’s opinion or advice however. I am a very logical person and if you can prove to me I’m doing something incorrect, I will follow. I’ve already been given some incredible advice here, thank you Tom for one. Tom has kind of taken me under his wing and giving me some guidance and I do appreciate it.

like I said, thanks again for the nice compliments. When I feel I’ve done something good, I can’t hardly wait to put a picture on here to see if you guys approve, LOL

this is been a great learning experience for me and I’m having fun
 

Tom from Rubicon

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Apr 4, 2016
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Tom, are these chain stays made out of stainless? And would it be too much for you to share your manufacturing trade secrets? I would like to do something similar on my future builds.
thanks
There is no vodoo Danny, I apprenticed as a Tool and Die Maker in 1969. By 1975, I added Mold Maker to my skill kit.

My Master Ray Nystrom constantly insisted, not to act and see the result. But to visualize how the tools we made would perform before the task they were designed for.

In the case of your brake arm hangers that clamp the chain stay, it was a matter of locating a 9/16” round as a mandrel, having a previously made open die, having multiple ½” rubber blocks to press the SS strap, the mandrel acts as a sizing punch. After multiple pressings the SS strap now has two upturned parallel sections of equal length.

A punch was made with a .718” sides and .359R bottom. Another temporary adjustable die was set up. Inner edges having 1/8” radius’s, to allow the metal to flow as it is forced into it’s final shape. A ¼” blade was used to set the internal width of the strap legs.

After multiple strikings of the punch on the ever narrowing die. And at all times the 9/16” mandrel is supporting the internal radius. You get the primary shape and fit. After drilling and deburring the clamping holes, my Kalamazoo belt sander/grinder generates the radiused tabs.
 

Tom from Rubicon

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Apr 4, 2016
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I should have taken photos. I won't.
Come to my shop. Or take a apprenticeship where ever. Community Colleges, have great programs.

In my early 50's I learned Auto Cad to the level of 3D modeling. Then Surf Cam for modeling to machine 3D surfaces.
Solid Works is now a driving software for machining. Metal forming software, even today is a joke. Proprietary.
Same goes for weld shrink values. Fillet size more than anything defines shrinkage.
Cat may have the shrink numbers. Mostly empirical.
Tom
 

Ralph hop

Well-Known Member
Nov 14, 2019
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Hey Danny just wanted to add that you have received a lot of great info from the forum members which have responded & I don't want to sound as if they gave you bad advice at all. I've found the comments and suggestions very good, but I know you like to read good posts from solid builders and Lurker's posts are good stuff because he was a newbie that tackled two tough project build back to back with basic hand tools and a plan, but he knew when to take solid advice and that spoke well of him.

Sometimes my posts come off as being harsh & and that's not at all my intent.

Rick C.
What Rick said. There was a few errors with my post regarding fork geometry. The different terminologies can get confusing. You always want the tires point of contact with the pavement out in front of the center line of the head tube which would would be the wheel axle center at 90 degrees. Wheel diameter changes the amount of trail also. A smaller outside diameter wheel and tire combo will reduce the amount of trail built into a bike. Larger diameter increasing it.
 

Nightster

Well-Known Member
Mar 3, 2021
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What Rick said. There was a few errors with my post regarding fork geometry. The different terminologies can get confusing. You always want the tires point of contact with the pavement out in front of the center line of the head tube which would would be the wheel axle center at 90 degrees. Wheel diameter changes the amount of trail also. A smaller outside diameter wheel and tire combo will reduce the amount of trail built into a bike. Larger diameter increasing it.
Thanks makes sense
 

Nightster

Well-Known Member
Mar 3, 2021
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