Correct. Thought other may like to see it
FF: Forks Thornton front shocker
- Thread starter Dave Hulstone
- Start date
Gotcha, sorry
Video about the Thornton Shock Absorbers
The advice in the video re speed wobbles is bullshit, no matter the origin of the advice. Having had a proper speed wobble, as opposed to a head shake, then it is not a matter of taking one's hands off the handlebars. The speed and violence of the motion is such that there is no way one could hold on to the handlebars. Mine occurred at one hundred mph on the long straight at Cadwell Park. The amount of kinetic energy of a total mass of, say, six hundred pounds at one hundred mph which is then being converted into oscillations is such that no normal human being, or a friction damper, will be able to control it.
Dave, IKON can change the valve, oil etc. I went through this with Geoff at IKON some years ago when he sent me a shock absorber I could hardly compress by hand. I sent him a fully rebuilt Vincent damper so he could compare and he sent back an IKON that was virtually the same as the Vincent item. Are you using Series D springs in the front spring boxes? I was always told that soft springs and firm damping is the best compromise unless you buy multi-thousand dollar suspension units. Like most things on a bike, when you change one part of a system you may have to change three. Also, I reckon Brian had done over 30,000km on that unit so it was well bedded in. Some people change their engine and gearbox oil regularly but neglect suspension oil. That is poor maintenance practise.
Yes I was lucky a few times , Then NOT !.
Get a Hydraulic Steering Damper, Only about £50, For me a Must Have.
I am without them here. Last ones on a bike, very nice.
I will ask if Hyerpro will do some for me.
as the pin at AVO is out of center.
I will ask if Hyerpro will do some for me.
as the pin at AVO is out of center.
I love Laney. He is a lovely guy but knows very little about bike geometry. When I spoke to him at a rally about a Series B coil over he was talking about an 80lb spring. Most of the development was by Works and Laney supplied the funds. Don't be too hard on him.
Hi Norman, I too have had a bad tank slapper but somehow managed to stay on, it was caused by badly ground cup and cone sets, in fact I was on my way back from getting the bike through it's MOT. I ended up hanging off the right (timing} side of the bike gripping the rear downpipe with my right knee and had a lovely burn to show for it. I can only assume that hanging off one side of the bike "destabilised the instability" if you know what I mean. Since fitting your JE column I've had a couple of minor wobbles set off by road surface irregularities coming off a bend on a rising throttle but they self-corrected very quickly and I now have every confidence that the new front end set up will cope with any eventuality, and I'm still running a friction damper. Cheers, Stu.
Al, the shocker Brian loaned me came with a heap of spares when he bought Bobs B series and sidecar off him and he’d never actually used it I believe. He did say that Bob had modified/serviced it though. I was an idiot not to compare the 2 when mine arrived. I just assumed that if an old one set up for a twin felt that good a new one set up for a single would be sensational.
You’ve made me think about the time period of changing shocker oil though. I have a fleet of bike in my shed, not all mine, and I can’t honestly remember the last time one of them had it’s rear damper oil changed. More ISO jobs .....