imported post
hi there.it depends how specific you want me to be:? at this stage i'll give you a rough idea . the last 4 trikes i have built have been done using this method because it works, it is quick,cheap and strong but still looks great.
i have a regular job 9 till 5 so i only get to work on the trike evenings and weekends, that said you can turn your old gl out on three wheels (dry built ) in a weekend.
if you can find a replacement swing arm you are on to a winner because you can build a bolt on back end that will definately fit that will take 2 men about 2 hours to change from two wheeled gl to a 3 wheeled trike.
i measure the distance from the swing arm bolts back to the rear wheel spindle (make a note of this for later) and the distance between the 2 bottom shocker mounts ( make another note)
i chop the replacement swing arm ends off to about 8 inches. it is important that these are chopped square and to exactly the same length( although actual length is not really important)
you now need 2 identical pieces of flat plate at least 6mm thick that are about 2 inches longer than the distance between the swing arm , arms that were earlier cut short. these need clamping or tacking together and a 10mm hole drilled in each corner
one of these flats needs to then be welded onto the end of the previously shortened swing arm, although a bit of thinking is involved. ..one side of the swing arm comes back at 90 degrees to the front face of the swing arm and one side bends out slightly, therefore the centre of the swing arm "arms" IS NOT the centre of the bike . so you need to find the centre between the swing arm pivots and mark it on the top of the swing arm. i find it best at this point to lay the swing arm on a super large piece of cardboard. lay the swing arm on top of the cardboard using the edge of the cardboard as a straight starting point.use a right angle to draw a straight line at a right angle to the swing arm pivots. this line needs to be about a metre long.
one of your previously drilled plates needs marking in the centre then offering up to the end of the swing arm "arms" making sure the centre mark on the plate lines up with the straight line drawn on the cardboard.
tack the stood up plate to the arms
on your rear car axle being used measure the distance from where you want the axle clamp to be on the right to where it wants to be on the left (make a note)
from your previous notes mark on your metre long centre line on the cardboard the distance from the centre of the swing arm pivots to the bike rear axle.from this mark, make another mark at 90 degrees out that is half of the distance between the axle clamps. join thise last 2 marks with a line.
now if you stand over this piece of cardboard looking down from the back end it will resemble a frame with swing arm at the front, a centre line marked up front to back and a line drawn where the axle will run...hopefully.:dude::dude::dude::dude::dude:
now your other plate needs bolting up to the plate that was tacked onto the end of the swing arm.
now you need to take 2 pieces of tube. these tubes need mitreing at each end, at the front to tack onto the flat plate and at the back to attatch to whatever clamping system you desire to use to attatch to the axle.
you now need to use a pipe bender and bend some smaller tube cut to length to span from the left to right on frame tubes.you need to do this so that the drive shaft has a clear straight run from the gearbox to the diff.also it ads strength and stops flexing, during welding and riding. the bottom shock mounts can also be mounted off this.
if you use a piece of string to double check , everything should be symetrical and identically proportionate, both sides of the swing arm
now set to with the welder , for a few hours.
clean up prime and paint
this is obviously a quick right up (although i'm not a typist and in reality took me ages) and i apologise if it is too mind boggling for you to comprehend. i have no problem if anyone should desire, i will take close up photos of mine if it helps understand it more:clapper:
bye for now
keep on triking
jim:waving: