Biggest problem with doing a leaf spring set up is finding a spring that is within your design parameters. It's been my experience that anything off a light truck such as a Chevy S-10 or a Toyota will work for anyone in the 125-210lbs range and give between 1-2 inches of spring travel. You want the leaf to be about 12-15 inches long with about 3-4 inches of bolt on space. Use spring clamps from the local hardware store but you might need to get a matching thread die to thread the U-bolts farther down like I've done here.
If your a heavier person you can simply use two leafs in a stacked set up or find one leaf from a heavier full size pickup. Problem is it's most likely going to be too stiff and will need some fine tuning. I hope you own a bucket of elbow grease cause your going to need all of it! The tuning process of a leaf spring entails using a large hand held grinder and a lot of moxie. You first need to use several cut off wheels and narrow the leaf its full length to about 2 inch wide. The starting at the rear, farthest from the mounting point, start grinding a taper from about 1/4" thick to about 5/16" thick at where it starts the mounting area. Also a longer leaf will have more flex, IE more travel, than a shorter one.
In every parts yard I've ever been it seams the going rate for a leaf spring pack is $20. Your still going to need to separate them and cut your piece to length but they are usually cheap and easy to find. Plus for you $20 you end up with enough to build several if you screw one up. Also don't overlook trailer springs. They are usually 1-3/4 to 2 inch wide and have a perfect spring rate for the average riders weight.
Lastly is the seat. A regular bike seat won't mount to a flat surface but a solo chopper seat will after drilling a couple of 3/8" holes in the spring. This where it gets very hard. Spring steel is very hard! Forget HSS drill bits, your going to need a Cobalt drill bit and a lot of oil as coolant. Take your time, set the drill on slow and keep the oil flowing. Go ahead and buy two bits cause you just might burn one of them up. I'm not kidding here, spring steel is tough stuff! If you can find a leaf with a hole in it already work around it when cutting you piece. Also to cut a leaf you will need an abrasive cut-off saw or a grinder with a cut-off wheel. Forget trying with a Sawzall unless you have handful of cobalt blades and a lot of free time! Just to give you an idea it took me over and hour to cut a 3/8" thick X 3 inch wide leaf with a Sawzall and about $40 worth of Cobalt blades.
4-1/2" cut-off wheels are dirt cheap and even though you might use a couple per cut that's still easier in the long run.
I hope this helps. Later Travis
If your a heavier person you can simply use two leafs in a stacked set up or find one leaf from a heavier full size pickup. Problem is it's most likely going to be too stiff and will need some fine tuning. I hope you own a bucket of elbow grease cause your going to need all of it! The tuning process of a leaf spring entails using a large hand held grinder and a lot of moxie. You first need to use several cut off wheels and narrow the leaf its full length to about 2 inch wide. The starting at the rear, farthest from the mounting point, start grinding a taper from about 1/4" thick to about 5/16" thick at where it starts the mounting area. Also a longer leaf will have more flex, IE more travel, than a shorter one.
In every parts yard I've ever been it seams the going rate for a leaf spring pack is $20. Your still going to need to separate them and cut your piece to length but they are usually cheap and easy to find. Plus for you $20 you end up with enough to build several if you screw one up. Also don't overlook trailer springs. They are usually 1-3/4 to 2 inch wide and have a perfect spring rate for the average riders weight.
Lastly is the seat. A regular bike seat won't mount to a flat surface but a solo chopper seat will after drilling a couple of 3/8" holes in the spring. This where it gets very hard. Spring steel is very hard! Forget HSS drill bits, your going to need a Cobalt drill bit and a lot of oil as coolant. Take your time, set the drill on slow and keep the oil flowing. Go ahead and buy two bits cause you just might burn one of them up. I'm not kidding here, spring steel is tough stuff! If you can find a leaf with a hole in it already work around it when cutting you piece. Also to cut a leaf you will need an abrasive cut-off saw or a grinder with a cut-off wheel. Forget trying with a Sawzall unless you have handful of cobalt blades and a lot of free time! Just to give you an idea it took me over and hour to cut a 3/8" thick X 3 inch wide leaf with a Sawzall and about $40 worth of Cobalt blades.
4-1/2" cut-off wheels are dirt cheap and even though you might use a couple per cut that's still easier in the long run.
I hope this helps. Later Travis
