68 Bonnie back on the road - where she belongs
I’ve wanted a Bonnie for the past 25 years after hearing a work colleague start up his newly restored pre-unit Bonnie and saying to myself ‘I will have one of these’. Anyway, February 2013 came and I purchased one that was due for some much needed TLC and nurturing back to how she once was. She was all there (ish). T140 parts, metric fasteners and various parts missing. She came with an MOT, no idea how it had one, it wouldn’t start for one thing but I didn’t mind, she was mostly all there and I knew from the outset that she would be stripped to the last nut and bolt, I was going to do this and enjoy the learning curve as I went along.
12 months passed and she sat in the same place in the garage where I’d unloaded her, if I was going to do anything with her I needed to start now before my enthusiasm weaned off. Over the coming weeks I tore her down taking hundreds of photos, bagging and labelling everything up and storing it in cardboard boxes labelled for each major part, forks, swing arm etc. I was now at the stage where I could send off the bright work to be re-chromed, frame etc to be painted and have some space back in my garage.
During the time this work was being done I bought a kit to do my own zinc plating. Once all of the plastic buckets were filled with the appropriate chemicals and happily bubbling away, I then took out each plastic zip bag of bolts and brackets, wire brushed all of the old muck off, cleaned and plated. A few days later I now had original and brand new looking fixings and fasteners. Over time some of the fasteners had been replaced with the wrong type so these were replaced with the correct fastener, bagged, labelled and stored.
I also knew by now what parts I needed to buy ready for the rebuild stage. Parts were being ordered week by week and deposited in the appropriate cardboard box ready for rebuild day.
A few months later, the chrome work returned along with the painted parts. I couldn’t resist putting the tank badges on the newly finished tank, I needed this little but of encouragement, there is a light at the end of the tunnel, it’s very faint but it’s there.
Life carried on in its way, family commitments, extensions to build, the poor old Bonnie was left neglected again as I struggled to find time for the second lady in my life. In January 2016 I knew that I had to get her rebuilt now otherwise come the spring I’d be starting another extension on the house and if I didn’t rebuild her now I think I’d of forgotten where everything went! For the next three months I spend evenings, the odd early hour and the occasional weekend putting everything back together bit by bit. First to be completed was the engine.
I’d already had the cylinders bored +20 thou and new valve guides pushed in. I’d cleaned the case with toilet cleaner – a cheap source of phosphoric acid. I also built an engine frame like the one Ed Hollingsworth built -
http://bullfire.net/Triumph/Triumph6/Triumph6.html .
Over the coming days the engine was rebuilt with new bearings, seals and gaskets etc. This was when I was glad I took hundreds of photos during the tear down. What seemed like pointless photos at the time made the rebuild so much easier. Nowadays photos cost nothing but boy do they tell a thousand words. I made a number of tools to help put parts back. Old clutch plates used to help rebuild the clutch basket. A hand reamer positioning tool to help fit the cam bushes, it’s so much easier when you’ve got the right tools for the job. You don’t need to buy them all, with a small lathe and some offcuts in the workshop most tools can be made for pennies. Eventually I’d got something that I’d of been happy placing in the living room and admiring its beauty but I think others in the house would disagree.
At this point I’d also got the wheels back from wheel builders, wonderful work. Now I had to start putting everything together again in the frame and finish off what I’d started a few years ago.
First to go in the frame was the engine. After reading that you should be able to put the engine into the frame with the rocket boxes on I went this route first. After laying the engine on its side and lowing the frame down it didn’t’ matter how I twisted things it just would not fit. Eventually after a few too many scratches on the frame I gave up, removed the boxes, and lowered the frame over, no problem, phew. The frame and engine was then strapped down to a table so the swing arm could be fitted followed by the forks and the front wheel. Gradually she started to look like something that could do 120mph – ish.
A few weeks later she had both her legs on and was able to stand by herself, ready for some wiring. I’ve read numerous posts on how daunting some people find this part. To me it was something I was looking forward to; having an electrical/mechanical apprenticeship I wasn’t put off by this step, so much so that I designed my own wiring layout adding in three relays to help switch the ignition and head light bulbs. Using the original wiring diagram I worked out what colour cables to use, bought a few meters of each along with the correct terminals and crimp tool and set to work. The following diagram shows what I made, straying not too far off the original but making it more ‘modern’. Once the loom was loosely made on the bike I then removed it and wrapped it in a cloth tape.
I decided to go with a three phase alternator (headlight still beams when the engine is idling) and three phase regulator. The regulator was bolted to the underside of the battery tray, out of sight but still in an air flow. I didn’t use the original Zener diode although it’s still on the bike with its white wire attached but the wire only goes into the loom a few inches and then stops. The same goes for the original rectifier, it has cables attached but they stop when inside the loom.
Reconditioned tacho and speed gauges were bolted in place and their cables attached. The seat was fixed and lastly the tank was bolted on, we were ready for take-off.
Start the bike for the first time is downright scary. I’ve never started a 1960’s bike before let alone my own one. As part of the engine build I’d followed Mr Pete’s recommendation of using Bon-ami to bed/lap piston rings. In fact I used a lot of people’s knowledge on Triumphnet in my rebuild, no more so than Rob ‘Snakeoils’ fantastic diary, a personal thank you to Rob for his indirect help. I’d also read how wise it is to start a newly build engine, get on it and head for the hills, idle it as short a time as possible. With all this going around my head I knew that it was now or never. Oil levels checked - again. No obvious sign of fluids leaking because I never did around to tightening the clamp up. Oil was seen going to the PRV cavity after a number of kicks, good. Time for make or break!
Three kicks later she roared into life, the phoenix had woken. Instead of doing what I knew I should do – ride her, I turned the key off and stared at what just happened, did it really happen? More checks for leaks, nothing yet, well, there’s nothing for it now, throw on my helmet and let’s go. The first trip of 5 miles was the scariest I’ve ever had. The route only had left turns back to home so I didn’t have to worry about sticking my hand out to indicate right. The brakes weren’t great but the acceleration was. The smile I must have had once I returned home was one of amazement, fright and pleasure. She’s a long way from being right but boy are we so close.
After a few months fettling, adjusting, tweaking and playing she’s now there. Start on the first kick now I learnt how to start her. For me it works if I turn on the fuel, tickle the carbs, give a couple of kicks to start drawing the fuel into the cylinders. Turn on the ignition, one more gentle kick and bang, she’s off. Of course now she’s at the stage where she’s ready to be enjoyed, here in good old Blighty it’s now winter meaning damp salted roads and darkness. All I want to do is to get on her and run for miles but this will have to wait for a few more months. Role on the summer!
When I bought her my uncle (in the first photo) – who also collected a number of classic and vintage bikes, he said that ‘once she’s finished you’ll buy another one’. ‘Never’ I replied, ‘one’s enough’. Sadly he died before I did finish but he was right, I am now looking for another project, something older I think, I fancy a BSA L31-4, anyone got one?
Chris