DIY Leaf SpringTruss Fork

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Gbrebes

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Jul 16, 2010
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Hey everybody, I made a fork similar to this a year ago, and I used part of a leaf spring from a golf cart. I found a group of 10 or so on eBay, and I have a bunch left over, so if anyone is interested, I could give some away. After having used just one single leaf, they are quite stiff, and I had to grind some of the spring material off to make it thinner. It still does not provide a lot of travel.

Gilbert
 

charliechaindrive.

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Nov 20, 2011
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I guess I'm not the only person who has thought of snomobile springs. A person could use the pair of them to make a replica of a indian cradle spring frame.
 

curtisfox

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Dec 29, 2008
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I guess I'm not the only person who has thought of snomobile springs. A person could use the pair of them to make a replica of a indian cradle spring frame.
I can get a pair for $20 is what I paid for the last pair. It might take some time like a month or so. Let me know so I can make some calls.
 

Russell

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Apr 19, 2009
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Hey everybody, I made a fork similar to this a year ago, and I used part of a leaf spring from a golf cart. I found a group of 10 or so on eBay, and I have a bunch left over, so if anyone is interested, I could give some away. After having used just one single leaf, they are quite stiff, and I had to grind some of the spring material off to make it thinner. It still does not provide a lot of travel.

Gilbert
How you setup your axle pivot arm can make a drastic change of : stiffness and axle travel

Fork @ C Spring rod @ B Axle @ A = max axle travel & minimum stiffness
 

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curtisfox

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Dec 29, 2008
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For sure: yours is setup with the axel in the rear and so it pulls down on the spring How is it for rake and trail?...............Curt
 

Russell

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Apr 19, 2009
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This setup was made to allow the axle to be either 1" fwd or rearward or 2" fwd or rearward of the original axle location. Only actual road test will determine which is best.
The adjustable length spring rods & the wide spring rod connection point allow this adjustment. The adj. length rod also allows for preloading the spring for more tension.
 
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Mr.B.

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Oct 21, 2008
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I built some of these a while back and because of wanting the Barn fresh look I bought a bundle of 3 rusty Model T Ford springs on EBay. I don’t recall the actual price but I do remember they were amazingly cheap shipped. Perhaps $20 - $25?

Trailing links are a just little smoother (imagine pulling a loaded wheelbarrow over a curb as opposed to pushing it) and the front end will dip when you brake. But to get decent trail the fork blades need to project forward a bit.

Leading links aren’t really bad though (IE; Harley used them until 1949) The front end will rise when you brake.

It took me 5 sets of links and 2 sets of front forks before I finally got mine right “-)

-Kirk
 

Russell

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Mr. B,
Good post, I had not even considered the braking forces. It seems that the effects would SOMEWHAT cancel each other with the leading link setup. The trailing link & brake forces would be SOMEWHAT additive.

I had looked @ a lot of setups before starting. It seemed that 75% were trailing links. I have gone with reversable links and adjustable preload.

The experimentation is what makes this hobby interesting. Sometimes science, sometimes art! I had assumed that I may have to make additional links, however only actual testing will tell.

Thanks for the info!

Jim E.
 
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Russell

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I just thought that a person could use some of the repop monark fork dropout thingers. That's what I'm using on mine
They may work super or they might just work ok, only trying others will tell.

Either way it's fun1
 
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Dave420

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Apr 22, 2011
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impressive write up .. when i first got on here, i was looking for an older bike to try this...someday
 

Russell

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Apr 19, 2009
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It was almost 60 Deg. today so I decided to test out the the leaf spring. I was supprised how good it felt and handled. When I lockup the front brake the nose dips some but adding another leaf would make it too stiff.
I could add another leaf and space them so it would come into play at max load but not really worth the effort.
 

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curtisfox

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Dec 29, 2008
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Re bump this to find out what was the final rocker position? and how is it working out?..................Curt
 

Russell

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Apr 19, 2009
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Curtis fox,
I still ride that bike, including a few tri state runs. I was damm lucky with that setup as it is the best feeling suspension I've ever rode. Not to soft and not stiff.

I have used it on three other builds and it seems that the longer the wheel base the better the ride. You may have noticed that I cold ground the leaf to match the expected load. I took the time to build bushings into the moving points and have served me well and the wheel remained true.

Jim

Another build with a trailing axle
 

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