FF: Forks Thornton front shocker

[Chris Launders]

Gary Gittleson, MartynG, Have you had the bearing conversion done as well, I was just using the AVO by then and on doing the bearing conversion the movement was so much freer I initially thought the damper had failed. I never actually tried the Thornton at this time as production had ceased and could see little point.

 

[Martyn Goodwin]

Gary Gittleson, MartynG, Have you had the bearing conversion done as well, I was just using the AVO by then and on doing the bearing conversion the movement was so much freer I initially thought the damper had failed. I never actually tried the Thornton at this time as production had ceased and could see little point.

Yrs I have the bearing conversion - its superb with a thornton

 

[Martyn Goodwin]

Not that we are 'permitted' to do any riding at the present - thanks Covid!

 

[timetraveller]

Hi Stu, how fast were you going? I suspect that elementary mechanics comes into this. The faster one is going the more kinetic energy which had to be dissipated through the front tyre leaving curved skid marks as it goes from lock to lock. In my case they went on for several tens of yards. I stayed upright gazing at the demon that seemed to be trapped in the steering system and only fell of when I got to the end of the straight where, unfortunately I landed on my face. No sales pitch here but remember that I can supply a complete hydraulic steering damper kit to fit the JE front end for £125 and that includes every part including the damper. You keep the original damper knob although it no longer serves a purpose.

 

[stu spalding]

Hi Norman, I was doing about 80 when a series of bumps set the front end off and everything was a blur until I found myself clambering back on board. I have no idea of the maths or physics involved but it would seem that my body weight, about 250lb at the time, would have an effect on some dynamics somehow. What I do know is that the oscillations were violent enough to shoot the tool tray out from under the seat and it was a good fit, retained by the standard clip and the lock from a car glove box. The tray was the only thing to suffer damage as when I went back to retrieve it I found that some kind soul had run over it! Cheers, Stu

 

[oexing]

Thanks for posting your mishaps which says a lot about having a good hydraulic steering damper on fast bikes. Even on our Bramptons I will no longer use friction definitely, just no suitable device , not fit for purpose from day one and not a smooth action on the road when tightened enough for having any effect at all.

Vic

 

[vibrac]

Here is my solution I shall be fitting next year. I have had the nut for years just never quite followed it up I think it is guiding the Lilly on a superb Branpton fork, but perhaps a situation could occur where a hydraulic damper would help. (coming down a rocky road in a snowstorm with a side wind?)
I will fit a standard telescopic damper to the head bracket as I have done on the racers (see below) sorry about the quality of the picture but the disgraced Comet is in detention until work starts in the winter.

 

[Gary Gittleson]

Gary Gittleson, MartynG, Have you had the bearing conversion done as well

If by "bearing conversion" you mean the bearing mod to the rear lower link, then yes. So far after several thousand miles, I have not felt the slightest wobble. I confess that I very rarely exceed 70 mph. I do however like to lean into the corners of which there are many in this vicinity.

 

[Mark Stephenson]

Gents
I am a new VOC member and am getting my first Vincent ('50 Series B with Bramptions) and would love to draft off your collective experience with what is the best modern front/rear suspension set up? Thorntons don't seem to be very available--can't find on the web. Any suggestions on what to buy and where to get it appreciated? Thx Mark

 

[timetraveller]

If you want to stay with the Bramptons then there is a photograph in the latest MPH of a new coil over damper to fit Bramptons. A batch of these is being made to order. If you want to change to girdraulics then there is another option which would take too long to describe here. For the rear a coil over damper from AVO in the UK and a fully sprung system to the rear of the seat will give you a much more comfortable ride.