Photos of 650SS

Matchless said:
My 1962 650ss crank was dynamically balanced by Bassett Down in Wiltshire at 65%. It is a delight to ride at any revs & regularly does the ton with remarkable ease, & all my fillings remain intact.

Martyn.
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Thanks, Martyn.

How about @worntorn? Did the vibes turn out to be the wheels or the engine?

Anyone know of a dynamic balancer on the US side of the pond (preferably west coast)? The list of trusted, competent grinders seems to shorten by the day. I've used Mile High Crankshafts in Denver, to good effect, but he doesn't dynamically balance, only static.
 
Most of the vibration was caused by out of round wheels.
After trueing the wheels, I had a look at engine mounts and the head steady.
One of the engine mount bolts was loose and another was misaligned . A bit of work with a die grinder fixed the misalignment.
That reduced vibes again.
Then I had a good look at the tank and seat mountings. The metal seat pan was contacting the frame. New rubbers fixed that.
The tank was bolted up with regular bolts and pieces of 1/4 rubber between tank mounts and tank. This is essentially solid mounting.
I found that the two front tank bolts, although not illustrated on the very poor Domi parts diagram, had 2 different part numbers. This made me think that the regular bolts in the tank were wrong.
I gave the part numbers to Mike Partridge at Walridge and, although he wasn't familiar with the bolts, he could order them and the proper tank rubbers.
He was surprised at the cost of the bolts, $16 and $12.
I was happy to hear that they were pricey as it seemed they might be special, and of course they are. They are shoulder bolts, the left side longer to mount the regulator heat sink, ( or was it the horn?)
Anyway , this arrangement clamps the tank to the rubber just like the Vincent tank mounts, only turned 90 degrees.
This helped to furthet reduce vibration as the tank is now isolated.
I still get some vibes through the footpegs at around 4 k rpm, might try isolating them.
Or perhaps do the dynamic crank balance as Martyn did.
Anyway, it is decently smooth now.
It would be good to ride a dynamically balanced 650ss to see if there is more improvement to be had there.

Glen
 
worntorn said:
Most of the vibration was caused by out of round wheels.
After trueing the wheels, I had a look at engine mounts and the head steady.
One of the engine mount bolts was loose and another was misaligned . A bit of work with a die grinder fixed the misalignment.
That reduced vibes again.
Then I had a good look at the tank and seat mountings. The metal seat pan was contacting the frame. New rubbers fixed that.
The tank was bolted up with regular bolts and pieces of 1/4 rubber between tank mounts and tank. This is essentially solid mounting.
I found that the two front tank bolts, although not illustrated on the very poor Domi parts diagram, had 2 different part numbers. This made me think that the regular bolts in the tank were wrong.
I gave the part numbers to Mike Partridge at Walridge and, although he wasn't familiar with the bolts, he could order them and the proper tank rubbers.
He was surprised at the cost of the bolts, $16 and $12.
I was happy to hear that they were pricey as it seemed they might be special, and of course they are. They are shoulder bolts, the left side longer to mount the regulator heat sink, ( or was it the horn?)
Anyway , this arrangement clamps the tank to the rubber just like the Vincent tank mounts, only turned 90 degrees.
This helped to furthet reduce vibration as the tank is now isolated.
I still get some vibes through the footpegs at around 4 k rpm, might try isolating them.
Or perhaps do the dynamic crank balance as Martyn did.
Anyway, it is decently smooth now.
It would be good to ride a dynamically balanced 650ss to see if there is more improvement to be had there.

Glen
Click to expand...


Thank you for taking the time to explain. First hand knowledge is getting thin on the ground.
 
Re tank bolt, there is a metal cup on the bottom containing rubber washer bolt threads thro frame mount then a thicker rubber washer on top b/t tank & frame. The 650ss was much the same as the Atlas as they both shared the same s/line frame and a lot of cycle parts but not all.
 
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@worntorn and all:

Two more things to check ......

1) magneto timing i.e. both cylinders firing 360 degrees apart.
2) tire balance.

After tuning my mag dead nuts on 360 degrees apart, and using Dyna Beads in my tires, I feel the vibes are supressed. Granted this is a very subjective assessment.

Slick
 
There is Boyer ignition on this bike, so no mag timing space to worry about.
Good point about the mag timing space. This is something I need to look at on the BSA A10, it has a Lucas mag and that bike does vibrate to a degree.

The wheels on the 650ss were balanced with tires on in the normal static way. Since then I've used a balancing sealing product called "Ride-on" with good results.
It works much like Dyna Beads for balancing and also seals leaks. It works best for sealing punctures on tubeless but also works on tube type tires.


Glen

 
Re tank bolts: If you convert to a modern regulator/rectifier and you remove the Zener Diode and its heat sink from under the petrol tank, you need to verify that the longer tank securing bolt on the left that held the Zener doesn't now thread far enough into the tank bracket to damage the tank.
 
When my Top hat washers perished, I baulked at the price of new ones so I bust used two tap washers each side suitably drilled to slide on bolt. 4 tap washers - much cheaper!
 
dynodave said:
I thought they were also commando seat washers?
Isn't that what I use? Or are you talking about the rubbers?
Click to expand...
Look at the bove referenced schematic drawings on the Norvil site and all will be made clear.
 
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