Honda CB400 Four resurrected after 30 years sitting outdoors…
The Honda CB400F is one of our favorite bikes from the entire CB series. It was an evolution of the CB350F, introduced in 1972 as the smallest four-cylinder motorcycle ever put in production. While the 37-hp CB400F did not have the outright power of the era’s two-stroke competition, the smooth-running engine, refinement, and sporty lines drew praise from riders and reviewers alike.
Enter Wayne Hawes of New South Wales, Australia, whose “End of Days scrambler” we previously featured. Wayne found the 1975 CB400F you see here while perusing eBay for a project. It turned out this particular model was for sale close to home, near an old racetrack. It only when Wayne started tearing down the motor that he learned the challenge before him:
“The first thing I did was drain any oil out of it and got a shock when around 4 liters of water came out first!”
Fortunately, Wayne apprenticed as a motor mechanic before he got into heavy industry, so he was up for the challenge. He brought the seized, sludge-filled engine back to life and rebuilt the bike into a cafe style. Besides the powder-coating and seat cover, he did all the work himself, including the re-lacing of the wheels and “Old English White” paint. Due to the lightweight nature of the build, he aptly the bike “White Lightning.”
Below, we get the full story from Wayne himself.
Honda CB400F Cafe Racer: In the Builder’s Words
I came across a beaten-up CB400F on EBay while looking for my next project bike.
It didn’t look too bad in the listing photos and was mostly all there but the motor was seized. I had never owned or ridden one but had read so many good things about the model, that I thought I’d take a chance on this bike, as it was for sale close to where I live.
It wasn’t till I started to pull the motor down that I realized how bad a condition it was in. The first thing I did was drain any oil out of it and got a shock when around 4 liters of water came out first! That was when I knew it wasn’t going to be an easy rebuild. It seemed the bike had an extremely hard life and possibly been raced at some time given its poor condition and it came from near an old racetrack.
The problems I found during the motor strip were too numerous to go into, so I will just list the bits that needed to be replaced for it to run again:
- Crankshaft and rods
- Camshaft and valve collets
- Cylinder block
- Pistons and rings
- Timing plate
- Clutch steel plates/ friction plates
- All roller and plain bearings
- Primary drive and cam chain
Along with all the parts I had to source, there was a lot of work to be done to the bits that where salvageable. As example, 75% of the head bolt holes were stripped and required helicoiling, the gear selectors unsized and just a whole lot of cleaning to remove the sludge from the water/oil mix in the engine.
In all fairness, the motor should have been junked but I could not find a good motor in Australia to replace it with. So I worked with what I had and sourced second hand and NOS parts where I could on the net.
Once the motor was rebuilt, I remodeled some parts I had to create the ‘cafe’ seat and rear cowling and fitted the clip-ons and fairing, then painted it the “Old English White” in my garage. A new wiring loom and mini gauges completed the look.
The only things I outsourced during the build were the powder coating of the frame and the recovering of the seat in the brown leather. The rest I did myself including the re-lacing of the wheels to the new rims and all the painting. I did have a friend with a press give me a hand with the gearbox bearings.
I removed quite a bit of weight from the bike during the build, hence the name “White Lightning.”
The things that I am most proud of on the bike are all the hand made bits like the seat and the fork brace that I made in my garage for the bike and the fact I bought it “back to life” considering the state it was in after sitting outside for 30 odd years!