Update November 7, 2011 - New entries will appear on this page. Links to
earlier episodes, see right column.
Bonneville, part 2
With the rolling chassis built it’s time for the “Dry Build”. When I say dry build, I mean the whole bike built in its entirety with every single part fitted. I’ve watched rubbish like “American Chopper” where the frame, chrome & paint comes back and they drill & grind fresh powder coating & chrome because they’ve forgotten something. It makes me cringe.
The first job was to make a paddock stand, then onto sheet metal, something I love doing. I have a home made folder & my trusty Chinese plasma cutter. I’m working with 16 gauge (1.6mm) because it doesn’t distort when welded.
The tank’s first. I love “wedge” tanks, they make the bike look like it’s doing 100mph when it’s standing still. This one wraps over the frame & is made from 4 pieces, the top, 2 ends & the base. It has to slide along the frame to come off. There are a few things to take into consideration. First, will it actually come off? Can I get at the bolts? Will I be able to reach the petrol tap easily? Where shall I put the breather? That all sounds obvious, but it’s pretty important. The whole tank was MIG welded and all the welds sanded with 36 grit flexible discs. There will be no body filler on this bike as everything will be powder coated.
The oil tank was next, always tricky as the fittings can stop it coming out. A catch tank was fabricated so the engine & oil tank can breathe into it. After that, the seat base and tailpiece, which is one unit, and proved to be pretty difficult to make. The seat itself has a separate base.
Finally, the chain guard, the most difficult bit of all. The regulations say it should be 3/16” thick. I didn’t have any 3/16” steel, so I doubled up with 16 gauge, meaning I actually have 2 guards, one on top of the other, & fully seam welded.
That little lot took over 3 weeks (full time). The next step is to fit all the parts, electrics, battery, controls etc. The battery was a pain, there was only one place it nearly fitted…..behind the engine, but even so, I had to notch out the down-tube.
A set of clip-on bars were made as (1) there were none commercially available, & (2) it saved money. With the bars on at last I could lay on it & work out the position for the foot pegs.
I had decided to go for rearsets, and to make life even more difficult, hand clutch & foot change. The rear brake was easy, simply a cable from the right hand foot pedal to the brake on the left.
The gear change was also not too bad, being a rod leading to a pivot, and a short rod down to the gearbox, all fully rose-jointed.
The clutch was a different matter. On the first attempt I made a cable set-up, which seemed to work fine, but I really wanted hydraulics, so that attempt was shelved.
I had a clutch master cylinder, but could not find a suitable slave cylinder, so I made one. It has a 12mm piston from a moped brake master cylinder.
The linkage you see allows me to adjust the piston travel, and I couldn’t believe how well it works, but that took care of another two weeks!
Check out the amount of parts involved.
Other jobs included fitting the IPE inlet manifold & Harley (Keihin CV) carb so I could fit a mounting bracket. After that it was bracket after bracket, steering stops, drill holes for switches & warning lights and finally make the exhaust from a pile of old British pipes.
Believe it or not, there was only one pipe from that lot I didn’t use! I’m now about 3 months into this build, that’s 3 months working all day every day, 7 days a week!
The final job was to strip the lot, weld
any parts I couldn’t reach, and de-spatter it. De-spattering is getting
rid of any residual spatter from the MIG welding. I do it with a sharp
chisel and a file, by hand. It’s tedious but well worth the effort. With
that done, it’s off for powder coating, and the finish is going to be pretty
special. How many powder coaters do you know who can reproduce chrome so
good you have to be inches away before you realise it’s paint? And he also
does candy apple powder! I’ll be having some of that, thankyou.
This is the story of Chris Ireland's 741 Land Speed racer.
A race bike built on a shoe-string
budget by sheer
For more information, or offers of help or sponsorship, contact Chris on firstname.lastname@example.org
Chris is the editor of Brit