David Rayner's Chopper Project.
This page is dedicated to the garage dweller, the X650 enthusiast who has that special project hidden away from prying eyes waiting for the day when he, or she, can take it for it's first ride. So if anyone out there just can't wait for people to see their pride and joy, and you want to share that secret project you've been working on for years with those who will be interested. Then this is the place!
Way back in 1980 I started building a chopper. I'd been buying American chopper magazines since the age of 12 and although they featured choppers made from many Japanese and British bikes as well as Harleys, I liked the Harleys best. So, a Harley it had to be. At that time, Harleys were very rarely seen in Australia and I was the only one I knew who had one. Long story short - it became a 9' 10" long bike with a 93ci S & S Sidewinder engine.
To this day, it's one of
the toughest looking bikes I've ever
seen. However, by the time it was around
80% finished (as seen in the pic above),
I realized it was way to radical and
would be a pain to ride. Just moving it
around the garage was almost impossible,
as it needed an area the size of a
football field to turn around in. I'd
also made a couple of fundamental errors
along the way, which could have been
rectified but not easily. So in the late
'80s and after much thought, I made the
painful decision to sell it. By that
time, Harleys were becoming like armpits
- everyone had two of them.
By the way, most people
who read this know me as one of the
founders of the 650 Club and many
consider me to be somewhat knowledgeable
on the bike, but there was a time when I
didn't even know there were two kinds -
the so called Standards or Roadsters,
and the Specials. The bike across the
road had cast wheels, a fat rear tyre,
and a stepped seat but the one I'd
bought had wire wheels, a skinny rear
tyre, and a flat seat but that didn't
matter. Either I didn't notice or didn't
care. Probably both.
I wasn't about to make that mistake again but the drawings in that book were only of Harley parts so I took the '77 outside and parked it on the centre-stand, stood as square-on to it as I could, and took a picture of each side. I had that processed (long before digital cameras), measured the distance between the axles, and compared that to the actual wheelbase. The idea was to have the pic either enlarged or reduced to make it 10% of actual size. Once I had that, I could work out any dimensions I wanted and proceeded to trace the new pic to end up with a line drawing of a 650 Yam in 1/10th scale. I could now design my new chopper on paper before I cut the first piece of metal. I decided on a swingarm frame, heavily modified, with hydraulic forks about 6" longer than stock. I can't find the original drawing but this is one I did a few years ago, when I briefly considered a girder fork and some fibreglass bodywork around the rear end. The original had great detail but this one only shows the major parts, the basic design having already been settled on. I've since decided to return to the original design.
Just to recap - The
first time around I'd chosen a bike that
very few people in Australia knew
anything about, I did not buy a complete
bike but a bunch of parts from here and
there, I'd never ridden that make of
bike, I didn't make any written plans as
to it's look but did it all in my head,
and I spent an absolute fortune having
the motor and gearbox rebuilt and
modified into an Earth-rotator long
before I needed it to run. I also
moulded and painted the frame and had
bits chromed as I made them. Thousands
of dollars and as many hours of my time
wasted. This time, I chose a bike that
was well known, I bought a complete bike
with a ton of spare parts, I rode one
before I committed to spending any money
on the project after the initial
purchase, I did some detailed drawings
of the proposed bike, I took apart the
motor and reassembled just the outer
parts and the trans output shaft to put
in the frame for fitting and fabrication
purposes, and I have no intention of
spending any time or money on making it
look pretty until I've put some serious
miles on it. If I'd done that with the
Harley it might not have turned out the
way it did but even if it had, at least
it wouldn't have cost half as much or
taken half as long.
He said he made all of it himself so I asked if he'd make parts to my designs, to which he agreed. He wrote his details on piece of paper and I went home to cut up the spare frame which, by the way, already had it's seat rails lowered by a previous owner.
I didn't like that but
the fact that it'd been already modified
made it the ideal candidate for further
work. I went to the wreckers and bought
the forks and triple clamps from a
Yamaha TT-600 and the rear wheel from an
'80 Special. This was in contrast to
importing a 15" OS girder which I'd
never seen in the flesh, and having a
custom rear wheel cast for the Harley.
The TT's front end had very chunky,
aluminium triple clamps, and 43mm forks
that were 6" longer than the 650's.
No need to buy extended tubes.
Having never cut up a frame before (the Harley's was modified before I bought it) I took a deep breath, cut the seat rails off, and cut the tubes that run upward from the swingarm pivot at a point intersecting where the new seat rails would finish if they were in line with the upper part of the backbone, and the entire rear end fell away. The tubes that run underneath the battery box were then removed, as they serve no purpose now. That done, the backbone itself was cut about midway between the top engine-mount and the steering head. The cradle was cut just forward of the bottom engine-mounts and the entire front end fell away. The engine mount was then removed from the remaining part of the backbone.
I then set the bike on blocks again but this time, with the front end suspended by a string from the ceiling as there was nothing to lean it against, a tank I'd bought from MCA, a rear mudguard off a H-D I'd bought from a H-D wrecker (such a thing didn't exist when I was building the previous chopper), and the seat which I still had from my Harley.
It would be a few months until I called the fellow with the chopper to arrange another meeting and by that time, I'd forgotten his name. It's a good thing he wrote it down - Peter Kommer - and as luck would have it, he lived only 30 minutes away from me. Together, we decided on a single down-tube with a gooseneck, and no cradle. Peter made and installed the new sections of the frame, turned up a new steering head to suit the TT's spindle, as well as axle spacers and several other small parts. This was done in just a few months but then he said he was moving house and so was unable to continue any further, at least for the time being.
While he was doing that, I was busy making up several minor parts. In the pics below, I'm making a bracket for the rear calliper, and cutting out some of the skirt on the rear 'guard.
This wasn't the end of
the world as I'd recently bought an XD
Falcon, which I wanted to rebuild into a
mild street machine. I brought the bike
home, parked it in a corner, and began
work on the Falcon. This required taking
it completely apart and so I needed
alternative transportation. I pulled the
'77 out of storage and after performing
a few simple checks for oil, spark,
etc., found the reason she didn't run
was because she was out of fuel. I
changed the oil, put fuel in the tank,
and jump-started it from the car. She
fired up after just a few seconds of
cranking so I warmed her up, put air in
the tyres, and took her around the
block. I got her registered and took the
Falcon off the road.
During the time the car
was off the road and I was riding the
'77, my father was nearing retirement
and wanted a project to keep him busy.
Having owned an assortment of Royal
Enfields, Triumphs, Nortons, and BSAs in
his younger days, he decided to build a
Triton (Triumph 650 motor in a Norton
Featherbed frame in the cafť racer
style). We looked at several examples
but after riding Japanese bikes for over
20 years and nothing British in that
time, he was shocked to discover just
how agricultural they were. I suggested
that a Yamaha 650 done in cafť style
would be a much better bike, but he
disagreed. A Triton was the fantasy bike
of his youth and I suppose he'd wanted
one for so long that nothing was going
to sway him now. Nothing that is, except
the stark reality of 40 year old
British bikes. He did the intelligent
thing and bought an XS and the story of
it can be found elsewhere on this site
The only reason it gets
a mention here is that it sent me off on
another detour. I now had a cafť racer
to ride and soon I'd have a chopper.
Whilst these are nice bikes to own, they
are what I call "fad" bikes -
they look great but are totally
impractical for everyday use, the
T-bucket of the bike world.
This is hardly an
everyday bike that can be ridden in all
weather, parked anywhere and left for
long periods, loaded up with tons of
luggage, etc. Yeah, I screwed up. By
that, I mean I didn't end up with what I
set out to have. An uncountable number
of parts were custom designed and made,
and a lot of it had never been done
before. Throw in a relationship break up
(thankfully, no kids), new girlfriend,
father dying, 2 kids, Ian Irving, moving
house twice, etc., and we arrive at
2009. Time sure gets away when you're
having fun. So, to cut a long story
short, it took many years more than I
anticipated and cost....don't even ask.
One thing is for sure
and that's that all telescopic forks
twist when raked to any great extent,
and this bike has 45 degrees. The reason
is that the more rake there is, the more
the front wheel falls over when the
steering is turned, and the wheel's
weight twists the forks. Thus, a fork
brace is mandatory and the only place
these forks can have one is where the
dust covers go. You can buy clamp-on
braces quite cheaply but my cafť uses a
one-piece item machined out of billet.
It's front-end came off the '77 before I
put the wide item on. The chopper will
have to have one the same or better and
that one cost $200 about 10 years ago.
The rear of the frame is too low for any shocks in the usual location so I'll run a short mono-shock off a sports bike in front of the tyre. It won't be a rising rate system, just straight swingarm-to-frame. Shocks like this are now common at the wreckers so it's just a matter of taking the bike there on a trailer and trying them on until I find the right one.
In the pic above, it's
still sitting on blocks with the
steering straight ahead but I've fitted
an old exhaust just to for fun and I've
also made a wooden seat so I can sit on
it to position certain things, relative
The motor will be much
the same as the '77 but with a few minor
changes. The ignition housing will be
see-through so you can watch it turning,
the clutch will have a window over it
for the same reason, and I'll probably
source the cam drive off a car instead
of making it all from scratch. Other
than that, it'll be a 90 degree 750 with
rods from a Honda CR-500 and pistons
made by Ross to my design. Valve gear is
Kibblewhite/Porsche. Intake is one like
you've not seen on a bike before and I'd
prefer to keep that to myself for the
time being, but suffice to say that I
won't be able to ride wearing loose
The steering head was made to suit the spindle of a TT-600 but since I sold those forks many years ago, I no longer need that. I could leave it there but Iíd prefer one off a 650 as itís quite a bit longer and when you increase the rake, you increase the load thatís applied to the steering head so the further the bearings are apart, the lesser the load is increased by. Itís all a matter of leverage. Anyway, I acquired a badly bent frame a few years ago and cut everything I could from it before scrapping it so since I have this steering head, I might as well use it. Here, itís having all the bits of frame cut away. Itís pretty rusty but a week in a bucket of molasses will fix that.
Well, after I'd cut most of the excess metal away from the steering head I noticed a hole right through one of the bearing surfaces. Bugger. I'm not sure if it rusted right through or was done by a PO trying to change the bearings with a hammer and chisel. In any case, it's junk. Time for plan B. I actually prefer the look of chromed bearing cups as on my Harley (go right back to the beginning if you want to see them). It's lucky I discovered I couldn't use the 650 item before I cut the one in the chopper out because now, all I have to do is simply cut the end sections containing the bearings off. I wondered for a while about how best to do that and finally hit on the idea of doing with the mill. Not only does it make easy work of it, but as long as the frame is positioned so the steering head is perfectly upright, the cuts should be square to the centerline so the new cups will seat properly when they're pressed in. Clamping it to an angle plate took care left/right and raising/lowering the engine hoist until a digital leveler read 90į to the table took care of fore/aft. Simple, really.That done, it'd be a miracle if the new cups happen to be a perfect fit into what remains of the steering head. I'm hoping they'll be too big as it'd be easy enough to have them turned down. If they're too small, it'll probably be by an amount too small to sleeve so if that's the case, I'll have to have them made from scratch. We'll see.
I went to a tube bending workshop recently to have some intake runners made for one of my other bikes. Since I was going there, it occurred to me to take the chopper frame to find out if the missing part of the cradle could be made.
Here is whatís there now.
Thatís a slug pushed into the frame right at the bend under bottom motor mount. I did that many years ago and never got any further with it. You can just see that the slug has split the frame tube at the end of the slot I cut to increase weld area. Thatís not good. Sure, it could be welded up but the whole idea of joining 2 lengths of tubing on a bend is a bad one. I didnít know that back then.
The nice people at the tube bending shop gave me a few pointers about what can and canít be done with tubing, and told me how to lay out a pattern or template for any length of tubing I needed, allowing for such things as the radius of their dies, minimum distance between two bends, etc. They told me to bend a piece of 1/4Ē solid round into the shape I needed, saying just one side would be enough as they could also make a mirror image of it.
I went home and thought about what I wanted and how best to make it. I marked out the start and finish of all bends in the cradle. TP is tangency point (where a bend begins), and MP is mid point of the straight sections. The frame has been dragged around the floor so the tape in the pic below has some of the marks worn off but Iíd already gotten what I needed from this exercise before I took the pic.
If you turn an XS frame upside down, youíll see the cradle has several bends that may not be apparent when the bike is all together and standing on its wheels. I made my cut at the mid point between the two marks which can still be seen on the tape on the opposite side.
Next job was to make something that would locate the solid round in the frame stub and keep it true. I machined this slug from a piece of solid aluminium I had laying around. The cut is so it could be a fraction bigger than the ID of the frame, yet still go in as it would collapse a little, and so be very tight. Any movement would lessen the accuracy of the template Iím making.
The hole going across it is to put a rod through to tap on when I want to take it out.
Here, the slug is in place and so is the solid round bar. In this shot, you can see why there is a bend under the motor mount. If it werenít there, the frame would be too far away from the motor at the front and look ridiculous. Actually, I considered cutting the frame past the next bend, reshaping the swing arm brackets, and beginning the bend in the replacement tube a couple of inches higher up. That would run the cradle right on or maybe a little above the motor mount. Itíd close up a rather large gap that, if you run high pipes and maybe I will, is now showing and not very pretty. But, that would require major surgery to the cross brace thatís at the bottom of the backbone. Way too much work. Just for once in my bike-building life, I let common sense prevail.
In this shot, you can see that the round bar doesnít follow the centre line of the bike. If the frame tube followed this path but with the aforementioned upward bend, it would foul on the motor so another bend is necessary (which a stock frame has Ė see the slug in the opposite tube) to straighten it. If I can, Iíll try to achieve two changes in course with just one bend and rotating the tube. By comparison, the cradle of an RD-350 is straight in both planes. Doing this to one of those would be so simple and easy.
I should say that the reason all this needs to be done in the first place, going all the way back to when I cut this frame up more than 20 years ago, is because I want a swing arm. You can buy very nice rigid frames with whatever rake you want but Iíve ridden with enough people who have rigids and seen the way they bounce all over the road. No thanks, not for me.
More to come.....