While many of us are sequestered to home during this horrible pandemic, our healthcare workers and essential service workers face the front lines with bravery and resolve. The rest of us can do our duty to follow best practices guidelines and send whatever donations we can to those in need.
Now is a good time to catch up on old projects that have been collecting dust and rust in the garage. I had exactly one such project: a 1968 BSA 250cc Starfire rolling chassis I acquired 20 years ago and a 1967 Triumph Daytona 500cc engine basement find from 15 years ago. The plan had been to build a mid-60s TriBSA; a BSA framed bike with a Triumph engine. BSA entered the ISDT (International Six Day Trials) with such machines using sturdy BSA frames and suspensions with reliable and tractable Triumph parallel twins. Photos shows the 1966 team.
The B25 frame I had was plenty strong enough. It was actually also used by the factory to house the 441 engine and 441 Victor Special off-road machines. The problem was that the cradle was too crammed for the Triumph mill, and none of the mounting tabs were anywhere close to fitting. My first thought was to cut and weld all new tabs, but with some thought, I was able to successfully make sturdy mounting plates that simply relocated the mounting points. All that was required was to weld a rear engine mounting tab. This was not to be a 'garage queen' show bike, but what a privateer may have constructed back in the day...sturdy and reliable.
The look I was actually going for was the typical mid-60s 'desert sled' off-road racer as shown in this photo of Steve McQueen's bike. I was simply looking to build a bike that can handle farm fields and logging trails rather than an off-roader hurtling over jumps at high speeds.
Working on the bike became a daily routine. The biggest challenge was moving the engine into the frame after having recently come off a hernia operation. A pulley suspended from the ceiling joist did the trick.
Another challenge was mounting the unit construction motor so that the front and rear sprocket aligned perfectly. Fortunately, both the B25 rear wheel and Triumph engine have the sprockets on the left side. This required the engine to be mounted just a touch off center...not a big deal at all. I used a laser pointer to help with the alignment. Engine mounts were fitted with shims and washers to secure the alignment.
The engine was in great shape but needed new clutch components and a few bits inside the transmission. I treated myself to a simple Mark I Boyer ignition, and haven't bothered yet to set up a charging system. At only 1 amp draw, this total-loss system will last me longer than I would want to ride off-road before the battery dies anyway.
The results are surprisingly good. Handling and tractability are excellent. Vibration is at a minimum for a parallel twin, and the high pipes I scored years earlier allow for a bit of log hopping. All that's left is to invest in a set of proper knobbies and possibly a skid plate.
So, dig through you scrap piles and sheds for something you have been thinking about for a long time. We may be in for a long haul.