1966 Spitfire - project officially done.

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started out with a well worn survivor, spent an on and off, 18 months on the restoration. fairly original example, but it needed just about everything. the bike was nut and bolt original with the exception of the carbs - original GP's were MIA. had one mod - boyer brandsen ignition system. the bike was showing 13K on the clock. teardown inspection yielded a good bottom end - squeakly clean - either a fresh rebuild, or this bike had very frequent oil changes. top end was standard bore but both pistons had hair line cracks - replaced the original 10.5:1 pistons with 9:1 and new rings. head had new guides, but the guide to valve stem clearance was excessive, but new valves (and springs) solved that issue. bike was completely rewired - couple upgrades - added a kill switch and front brake light switch. mods - new pazon ignition and new amal 930 premier concentrics. all new chrome plating by space coast plating here in florida, a few service replacement parts - rear shocks, brake shoes, clutch plates, some new rubber pieces/parts etc.. frame paint - budget rattle can, tank and side covers - skuff/sand and top coated with single stage urethane - computer color matched by higgs auto paint here in daytona. didn't build for show, but for an everyday, head turning, daily rider. took a while to sort thru some minor issues, mostly carb and ignition, but all seems well. a spitfire's been on my bucket list for some 50 years - check off another one -

1966 Spitfire - project officially done.
 
Last edited:
started out with a well worn survivor, spent an on and off, 18 months on the restoration. fairly original example, but it needed just about everything. the bike was nut and bolt original with the exception of the carbs - original GP's were MIA. had one mod - boyer brandsen ignition system. the bike was showing 13K on the clock. teardown inspection yielded a good bottom end - squeakly clean - either a fresh rebuild, or this bike had very frequent oil changes. top end was standard bore but both pistons had hair line cracks - replaced the original 10.5:1 pistons with 9:1 and new rings. head had new guides, but the guide to valve stem clearance was excessive, but new valves (and springs) solved that issue. bike was completely rewired - couple upgrades - added a kill switch and front brake light switch. mods - new pazon ignition and new amal 930 premier concentrics. all new chrome plating by space coast plating here in florida, a few service replacement parts - rear shocks, brake shoes, some new rubber pieces, etc.. frame paint - budget rattle can, tank and side covers - skuff/sand and top coated with single stage urethane - computer color matched by higgs auto paint here in daytona. didn't build for show, but for an everyday, head turning, daily rider. took a while to sort thru some minor issues, mostly carb and ignition, but all seems well. a spitfire's been on my bucket list for some 50 years - check another one off -

1966 Spitfire - project officially done.
You'e done a great job, the bike looks fab
 
Just have to ask: how do you find the engine vibrations?
 
I asked not to pull your chain but to see if it was possible to keep them with in a reasonable
level. My 71 Lightening was less than acceptable. Otherwise a nice bike.
Did you have the crank balanced dynamically?
 
Vibration is a problem on every one of the solidly mounted British Twins, in my experience. The best solution seems to be the English B road and forty mile an hour fun.
At 70 mph for a 3-400 mile day on our highways the average British Parallel twin is shaking the rider way too much to be fun.
I'm lobbying for the building of Canadian B roads!

Glen
 
I asked not to pull your chain but to see if it was possible to keep them with in a reasonable
level. My 71 Lightening was less than acceptable. Otherwise a nice bike.
Did you have the crank balanced dynamically?
didn't do anything to the bottom end. as far as i know, as it left the factory. vibration is, IMO, very good. i can't say if find anything objectionable vibration wise. my 70 daytona was so bad, the speedometer/tach was nothing more than a blurr at 50MPH. not so with spitfire - very little vibration thru the hand grips and footpegs, but that's about it. to be honest, i'm somewhat surprised how smooth it is for a solid mount.
 
Must be a bike built on Wednesday....:)
I had an oil in frame lightning
The vibration was terrible but my mate has a thunderbolt of the same vintage that he claims to be dead smooth!
 
Beautiful bike! I also have a 66 Spitfire. Amal GP's are on the shelf for premier concentrics. Mine vibrates enough that it eventually gets annoying on a long ride. Made me realize how much I like the isolastics on the Commando.
 
I had an oil in frame lightning
The vibration was terrible but my mate has a thunderbolt of the same vintage that he claims to be dead smooth!
yes i had 72 OIF Tbolt it was smooth my pal owns it now my 68 A65 buzzes at 45mph but smooth at 50
 
I had a '69 Lightning which I was convinced might explode if I tried to take it over 4,500 revs. The vibration was truly horrendous. I had the crank dynamically balanced to 68% by SRM. The difference was remarkable. Just got the crank back from dynamic balancing for the OIF '71 Lightning I'm building. I'll report back once it's running.

Martyn.
 
I had a '69 Lightning which I was convinced might explode if I tried to take it over 4,500 revs. The vibration was truly horrendous. I had the crank dynamically balanced to 68% by SRM. The difference was remarkable. Just got the crank back from dynamic balancing for the OIF '71 Lightning I'm building. I'll report back once it's running.

Martyn.
I did once hear of an A50 that vibrated badly until it was discovered that the flywheel was bolted on in the wrong position from the factory
There were marks where the holes for the crank should have been apparently
 
I remember reading a test of a '65 Lightning in Motorcycle Mechanics & Three Wheeler magazine. The tester said the bike vibrated badly, when in those days it was unusual for the mags to be overly critical. It's a pity the factories, with the exception of R.E., didn't invest in dynamic balancing equipment. Having said that, it's a pity they didn't do a lot of things. I did hear that AMC dynamically balanced twin cranks later on in production but don't know for certain.
 
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