Going to skim though some pictures of my new chopper build and put some words to it for you all. Hope you like.
Nice molded bigtwin rigid frame with some some subtle changes from stock.
Freshly soda blasted (bicarbonate soda) engine and gearbox. It’s not as agressive or effective as grit blasting, but it’s fine to use Assembled motors, it just breaks down and washes away.
Shaved top tree and Polished the fork lowers. These are pretty beat up from the previous life, but it will be replaced by a springer in the future so I’m not too concerned about them for now.
Becomes a rolling chassis pretty quickly. Same wheels as used previously, it’s a 70s Yamaha front hub with 21” rim and a CB750 rear hub with Harley 16” rim.
King Peanut tank holds about 9L. 6” flat guard mocked up. 5/8” stainless sissy bar feauturing the “South Bay swoop”, a popular addition on 70s choppers from that area. Makes the sissybar massively strong and takes away its reliance on the rear guard for support. Playing with sissy bar infil designs.
Stainless foot control pedals and pivots. The backing blare is painted steel but will be replaced with stainless at some point. I wanted really simple foot controls and 1/2” stainless round I think is very tidy. The first 1.5” of the solid 1” foot peg is turned down, with a section of 25x3mm stainless tube used as the pivot sleeve. Just lightly greased periodically and it works great. Yacht fittings used for the brake cable, there was no room to run a solid rod through to the rear brake.
Decided to use a King PNut tank from Lowbrow Customs, it’s a slightly scaled up version of an original peanut/wassel tank. High filler and low tap means all the fuel is useable. One of my biggest frustrations, when I look at some awesome looking choppers that can only access 3/4 of the tank capacity.
I’m lazy, and often find ways of doing things a bit more “custom” because it’s easier than the alternative. Case in point - the seam of the two tank halves right is linished smooth from the factory, but the crown/contour of the tank is uneven. This could be smoothed over with filler, but if I’m gonna use filler then may as well go further. So there you go, thus became the 10mm round bar peak. Racked in with the ends smoothed over, then molded in filler.
I cut off the original tank mounts and put my own on, although they are in the same style. This is because the frame was originally set up for a frisco sporty tank, something which i wanted to keep for adaptability in the future. I can make the mounts on this tank longer, but Ya can’t make a sporty tank any shorter!!! Not easily anyway.
Jumping around a bit here, but here’s my seat with foam roughed on it. All the blue is closed cell foam that is quite firm to the hand, but it’s always surprising how much energy a 100kg sack of flesh, water and bones generates bouncing down the road. The black foam is softer. The cutout with the pink foam is quite soft, and is placed underneath where my coccyx is, have bruised it before
After this picture, I glued down a full layer of the black over the top of the seat. This is also close cell EVA foam that I cut from excercise mats, cheap from Target. They make great mats to lie on shed floors with too!!
Left side showing the half open primary, modified from a stock cast inner primary with a polished aluminium outer. New 5 stud clutch hub, pressure plate and chrome outer plate, performance clutch springs. BDL 1.5” belt drive.
Also visible is the shifter linkage and sidestand. I have ridden jockey shift for a long while and footshift actually feels unnatural now, but I wanted to try it out as it will make filtering through traffic much less stressful. Let’s see how long it lasts.
Sidestand is a stock length reproduction. I much prefer this design over other custom styles of sidestand, it works really well and is quite strong. One design HD actually got right in the early days, and held on to it for ever. Look at some of the most radical and out there show bikes of the 70s, most still used a stock Harley stand.
Also visible is the oil tank which was carried over from previously, but has had a brushed stainless skin welded to it. I’m not happy with it and it has some minor leaks so this will be getting replaced soon.
1 3/4 stainless pipes coming together. I had made a template for these to be mandrel bent, but either there was some inaccuracies in the bending or more likely my templates!! I needed to cut them and adjust in one area of each pipe.
Passenger foot pegs mounted up, and a good shot of the CB750 rear drum that I’ve run for a while. Prof has the same setup, I can’t take any credit for it!!
My switch panel is on the back of the oil tank, and the swoop on the sissy bar.
Oil filter mounted to the back of the trans plate, makes for really clean and easy filter changes.
Rear brake cable now run and snaking along the frame. Visually I would prefer solid linkages with belcranks, but even then it was difficult to package amongst everything and I was trying to get this project moving.
Doing a test panel for the upholstery. Marine vinyl with a backer of ripstop nylon, sandwiching 6mm very soft foam.
Here’s my trick on getting nice even pleats. With the vinyl laid out flat, I marked my lines with 50mm masking tape, first one direction then the other. Making sure the tape going on straight and level, leaving an approx 2mm gap in between each piece of tape. The area between the tales becomes your sew line, makes it very easy to follow as the contrast between black and white really helps the eyes following the lines. I didn’t sew this masterpiece however, a good friend did. Even still, she is a brilliant dressmaker but this was her first attempt at anything upholstery.
First stage done, now taped up and ready to go in the other direction.
Here’s the pleated top now ready to sew against the boxing. I’ve done a few simple seats myself and this is a trick my mum told me, holding everything together with bulldog clips. I have a big jar of them and you just clip the whole thing together, then as you sew 1” at a time, pull the clip off and throw it aside.
Seat Finished!! Apart from being pulled over glued down to the base. The fanciest seat I’ve ever had that’s for sure.
Here’s the paint work for the tank and rear guard. I’m planning to do the whole frame in this style too, but for now the frame is just spray canned black to get this thing on the road. I also wanted to do some good roadtesting before doing the proper frame paint, in case any tabs need to be added/removed or other alterations. If I do, it’s easy to touch up now without ruining a good paint job.
This is all spray cans. Dulux light blue base, with their marble effect spray over the top. Really interesting stuff to use. In general, spray paint atomises when it leaves the can, and you have your work piece fairly close. The marble paint is essentially unthinned paint and comes out stringy, but when it leaves the can it just keeps going until it lands somewhere!!! Be aware of your surroundings using this stuff!
The whole thing is then buried in Spraymax 2K clear, a top quality fuel proof 2K/2pack. Expensive per can but it’s the same quality you’d get in a pro paint shop. 2 part spray can needs to be activated then used within a period of time. 1 can used for the tank and guard - 4 heavy coats.
Bike all together and ready to ride. It was all a mad rush to get it done, and I’m pretty happy with how it all turned out. There are things that I need to redo, things that I need to finish. The oil tank is one thing that will be replaced. It’s leaking and has been rewelded several times already.
I’ve put a few hundred Kms on the bike now, and it’s riding superb. My first rigid and I’m very impressed with its ride quality over a variety of roads.
Now that I’ve got this thread up to date, I’ll try my best to update it as things occur. Bike is sitting now minus an oil tank, it’s replacement is the first thing that needs to be done amongst all the other jobs in ones busy life. That will get the bike back on the road again.
In the background I will begin working on my springer. As it turns out, both Prof and I are building springers front ends using hydraulic shocks instead of the typical compression/rebound spring setup. Our designs will be quite different in appearance and construction so it’ll be interesting to see how they both end up and handle.
Cheers.
Its a viscious cycle !! 
