I sent them an AVO front damper yesterday as well. It is not just the physical size and fittings etc but it will also be interesting to see whether they would recommend any differences to the damping. One particular thing that I would like to see sorted out, if it is possible, is the fact that with the AVOs we had to get a stiffer damper made as the standard ones, which works very well with low to medium weight riders, could not be adjusted stiff enough to control the bouncing action of the bikes eg a twin with a 300lb rider. It would be nice to find out whether a single damper could have enough range so that one model would suit all riders.
F: Frame AVO COIL OVER WANTED HELP PLEASE
- Thread starter kerry
- Start date
I am not being judgemental (I can't really afford to be) but twenty one and a half stone is quite heavy, perhaps it is asking quite a lot of a one size fits all shock.
A shorter D shock seems to be advantageous to some riders, me included, using the AVO short version, the difference in performance was not noticeable, but the reduction in seat height certainly was.
You may be right Peter but there are at least two people out there riding twins with JE front ends who are that weight. No point me not asking.
I have been chatting to Kevin and Tim at Protech this morning and Kevin says that since making my front damper they have designed a lighter weight valve which would overcome the problem of making it soft enough. One problem we did find is that the adjustable damping valve takes up room in the base of the damper and prevents it closing as much as the original Vincent damper or indeed the Armstrong. Never the less mine gives enough movement as they have made it.
Brian
Brian
Norman, didn't you need two different front dampers depending on whether the roller bearing conversion had been done or not, I remember when testing them that when I changed from the bushed front end I thought my damper had failed as the reduction in friction was so great.
Chris.
Chris.
looking at Chris's comment above, you can see that if you did away with the front spring cases all together and changed all the FF 6 bushes for needle rollers, the front end becomes near friction less........That with an adjustable coilover in place of the shock on its own gives the ultimate Vincent front end.......Its a lot of work but definitely doable......All good fun.
Hi Chris, that is correct. You started off with 36 lbs/inch springs and the standard AVO front damper. When you changed to needle rollers as replacements for the Oilite bushes (instead of Greg's mod of two ball races each side) you thought that the damper had failed. It went back to AVOs for testing and was found to be in good order. That is when I got AVO to make some specially stiff dampers. Those stopped the pogoing effect but you still had to go up to 45 lbs/inch springs with about 5/8" of packing to stiffening the springing. I did mention a few day ago that once the new lower links are made it might be possible to modify the machining program to leave more metal around where the FF6 bronze bushes go so that needle rollers could be inserted there. The problem I envisage, but I am doing other stuff at the moment, is that it might be difficult to find imperial needle roller bearing to fit the spindles. Changing the spindle size is probably a step too far for most people.
Regarding Brian's posting above. #85, when John Emmanuel designed the new geometry it was for handling while racing. John just used different strength springs until he found what he regarded as satisfactory but he did not know what strength they were. When I started making them available I had to calculate what I thought would be suitable and then realised that the comfort could be improved by using as much travel as possible within the constraints of the existing design. I managed to get about 3" of travel and most people who use the bikes for touring seem to find that is a nice figure. Both Chris Launders and the Tilleys have made videos of the front fork movement and those videos can be found on here. They perform as I intended.
There might be some wriggle room when it comes to the travel of the front damper. Note that the original Vincent damper is about 3/8" longer than both the AVO and the earlier Armstrong. One has to use the longer lower eyebolts with the shorter dampers but it is possible that going back to the use of the original eyebolts and making use of the potential extra 3/8" damper length might allow the damping system to be installed and have the extra movement. We are not talking one or two millimetres here. Whether the total travel is 75 mm or 70 is probably not important to most people.
While discussing damping rates; I wonder whether the pneumatic dampers discussed by VIC have different damping rates between compression and extension. It is really important that the extension is more heavily damped than the compression for maximum comfort and safety. I noticed while looking through the Protech site this morning that some of their dampers have two adjuster knobs on them. If that is one for compression and one for extension then that might be exciting.
Regarding Brian's posting above. #85, when John Emmanuel designed the new geometry it was for handling while racing. John just used different strength springs until he found what he regarded as satisfactory but he did not know what strength they were. When I started making them available I had to calculate what I thought would be suitable and then realised that the comfort could be improved by using as much travel as possible within the constraints of the existing design. I managed to get about 3" of travel and most people who use the bikes for touring seem to find that is a nice figure. Both Chris Launders and the Tilleys have made videos of the front fork movement and those videos can be found on here. They perform as I intended.
There might be some wriggle room when it comes to the travel of the front damper. Note that the original Vincent damper is about 3/8" longer than both the AVO and the earlier Armstrong. One has to use the longer lower eyebolts with the shorter dampers but it is possible that going back to the use of the original eyebolts and making use of the potential extra 3/8" damper length might allow the damping system to be installed and have the extra movement. We are not talking one or two millimetres here. Whether the total travel is 75 mm or 70 is probably not important to most people.
While discussing damping rates; I wonder whether the pneumatic dampers discussed by VIC have different damping rates between compression and extension. It is really important that the extension is more heavily damped than the compression for maximum comfort and safety. I noticed while looking through the Protech site this morning that some of their dampers have two adjuster knobs on them. If that is one for compression and one for extension then that might be exciting.
TT,
Two members came to me as they were unable to use their AVO front dampers (a Comet and a Rapide). They were too stiff and would not move on their front forks. AVO was not able to supply lighter units and the dampers went on the shelf. I had a Works Performance damper for the first gent, but it was my last. I suggested a Maughan damper for the second gent, but I have not heard a review from him. I think it would be nice to explore that damping information.
David
David, if it is possible can you find the numbers stamped into the base of those dampers.1447 was the standard ones and 1448 were the stiffer ones. Until I had sold a few and had feedback I did send out some of the stiffer ones as they seemed to be the favourites. I exchanged several back from 1448 to 1447 when people found they were too stiff. I also sent out 45 lbs/inch springs for all twins as Greg prefers stiffer springs. The consensus in Europe is that the 36 lbs/inch springs and the normal AVO damper suits most people and I have swapped 45s for 36s for some people. It is probably not possible to exchange them now as AVO has closed down but it might be an explanation for what was wrong.