Before I start, please note that this bike had sat in a garage idle for 26 years. I spent a couple grand to put this bike back on the road. During its service life, the electrical system on this bike was quite inferior. The ignition system was fraught with troublesome possibilities. Cables were unreliable.
The bike is great to ride and be seen on. It sounds like nothing else on the road and looks like nothing else out there. Its 60's looking style is a major eye catcher. Add a classic leather jacket and chauffeur's leather topper for full effect.
This Thunderbolt usually starts in one or two kicks, thanks to the up-dated electronic ignition. The lights are bright, thanks to the up-dated charging system. I strongly recommend these updates.
This model with its in line 650 twin has some deadly serious low end torque. This feature demands one's extra care in using the throttle. The Thunderbolt could get away from a novice. Noted is vibration at high RPM. You can tell you are exceeding 70 mph without looking at the speedometer.
Roll on power is abundant at all speeds. This particular bike's clutch does slip a bit, so a down-shift is needed to accelerate without the slippage. It sings the song of the highway with a throaty British accent. It's become my personal siren song that lures me to the road, even when I have no place in mind to go.
It's not perfect though, is it? One sits rather high on this style of bike. I feel like I'm teetering at low speed. You need to go faster on this bike. Not having disk brakes does require a harder squeeze to stop and a harder step on the rear brake as well.
Handling is bittersweet. This shorter wheelbase does suggest more maneuverability, but your higher center of gravity makes it somewhat perilous. The BSA standard replacement tires are just the sort you would want for all weather riding. The aggressive treads bite the pavement like a pit bull even on wet pavement. This inspires my confidence in spite of my stated handling issues with "The Beezer".
One amusing thing about my bike that you might watch out for if you are building or restoring one like this... The guy who worked on my bike took it upon himself to replace the rather ratty looking rear wheel. I was glad for that. I did find that the speedometer was off quite a bit. I asked my brother (from whom I bought the bike) if it was off when he had it and he told me, no. Apparently this replacement wheel has a metric speedometer drive. The speedometer which says MPH now shows KPH. 120 is about 70 MPH.
I couldn't agree more re the sound of these motorcycles - there is nothing like it! Mine was a 1968 Spitfire markIV. Rode it cross country with little trouble - and cruising is definitely not what it was designed for. Enjoy!
I too owned a BSA, mine was a 1967 650 Lighting. This is a super bike. With a set of Dunlops I was able to put the old thing just about on the pipes in turns.
But the Lucas electrics were terrible (hence the term Lucas God of Darkness), and you are right when you say there is lots of low end torque. One really wants to know what they are doing when you grab lots of throttle in first and second gear!
The only thing that I owned that was a tad wilder was my Ariel Sq 4, but then again that was a 1000cc bike.
I currently own a 1970 Firebird, actually just rebuilt from a box of bits. I note the sarcasm about the electrics; mine have failed on a number of occasions, and only last Sunday 80 Klm's from home, caught fire at the ignition switch. Apart from that what a great bike.
I'll guess the vibration inherent with the vertical twin is a possible cause for trouble with the electrics. Anything not insulated from the vibe could be shaken to death.
On my way to Kansas from Tulsa, the beezer lost a bolt out of the headlight. When fixing this, I discovered stress cracks in the headlight assembly. I had to cobble the thing back together against the day I find a headlight can that belongs on it.
I was reading that recent Triumph Bonneville models have a vertical twin 865cc that is internally counterbalanced. Much smoother, however, it vibrates at higher speeds. I think they all do to some extent.
I bought it brand new in 1970. The Thunderbolt came in black or red that year. I wanted a black one, but the dealer only had one, and it was red. I would stop by on my way home after work every night when my, 4:00pm until 12:30am shift was over. I just had to look in the window to make sure it was still there.
I finally had enough saved up to make a down payment on that $1,300 BSA. Soon I was riding 50 miles round trip, back and forth to work every night, after having spent hours during the day polishing it. It dripped oil all over the garage floor. The gas cap never sealed well, so when full, it would spew gasoline all over the red top and down the chrome sides of the tank. At freeway speed it vibrated so bad it put my butt to sleep, and eventually the one mirror broke off and landed somewhere on the freeway.
The lights would invariably shut off on the way home in the middle of the night, and I’d have to replace another headlight bulb. Another night not far from home, the electrics went out and the engine shut down.
A rocker arm broke on a trip home one night. Rather than chain it to a pole or something sane like that, I walked that Thunderbolt the last 8 miles I had left to get home. I loved that bike.
A few years later a co-worker asked if he could try it out. Stupidly, I said okay. He promptly crashed it into a curb, broke the bike and that broke my heart. I knew that bike would never ride the same, nor would I ever feel the same way about it. When he offered to buy it if I would help fix it, I did and he did. I’ve had other bikes since then, but none like that red Thunderbolt.
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