Vincent, Where was the fault with the AVO shock, what pin was out of centre, do you mean the shock shaft?
FF: Forks Thornton front shocker
- Thread starter Dave Hulstone
- Start date
yep
I put the AVO one on my twin. It is a way better ride than the modified original type I had before. The damping on the AVO is adjustable by a little screw.
I happen to have my Thornton front shock apart on my work bench right now, though it is a coil over version. I also have the same manual from 6/97. Reading it carefully it seems that the difference in front and rear shock damping, at least in ‘97, was in the rebound damping only. The compression was controlled by 3 springs of different lengths and strengths controlling 3 ball bearings in orifices. While it does not say so specifically, it implies there were no variations in this valving front and rear. The difference is in the rebound damping and is controlled by flapper valve discs of either .010” or .015” thickness, with the thicker disc resistance being equal to three thin ones. My front shock has three of the thinner .010 discs.
Dave, it may be that you can modify the one you have by following the instructions in the manual and checking what flapper valves are fitted to the piston and decreasing the resistance they offer to rebound by removing one. It also warns in the manual that if the internal nut on the piston loosens, the discs can rotate and block the holes, partially locking up the damper, and the same effect is possible if it is overfilled.
I also notice that the recommendation for 5 wt oil is crossed out and 10 wt is handwritten in. I wonder about that.
Dave, it may be that you can modify the one you have by following the instructions in the manual and checking what flapper valves are fitted to the piston and decreasing the resistance they offer to rebound by removing one. It also warns in the manual that if the internal nut on the piston loosens, the discs can rotate and block the holes, partially locking up the damper, and the same effect is possible if it is overfilled.
I also notice that the recommendation for 5 wt oil is crossed out and 10 wt is handwritten in. I wonder about that.
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While doing some of the Road testing for the JE steering stem I was testing dampers back to back and in my opinion the Thornton was marginally better than the AVO, but not really enough to warrant the extra cost and of course they are no longer made. When the bearing conversion is done totally different damping is needed so the Thornton would be no good then.
Chris.
Chris.
I have mentioned this elsewhere, but while Works Performance is gone, this company was formed by former employees. They seem to be more interested in off road and modern bikes, but they might be able to supply internal piston replacement parts for the Vincent Thorntons if you have a good one that needs a change in tuning. It may be worth a call or email.
I am using the JE steering stem with my Thornton shock. Seems fine to me.
Me too
A 'proper' speed wobble at 70 MPH was sufficient to shatter my right wrist and bend the bars on the right side. Bike off in one direction, me in another. Both bike n I landed and slid on left hand side. No damage at all to the right side of my clothing or right glove but as I said right wrist shattered.
No damage at all on right side of bike other than handle bar bent forward on that side.
Forces were unbelievable.
At time bike was fitted with friction damper - now has hydraulic steering damper AND the JE head stem. Still some minor headshake on uneven corners but all quickly damped.
I could not remember if he went up or down, but Dave will figure out what he likes.
David