For anyone else having problems the caption reads: "Custom spring box adaptors for Thornton springs. Lubricated piston rod guide borrowed from the age of steam. #4050"
Best input sought to update front and rear suspension ?
- Thread starter Steve F
- Start date
AVO are now offering a hydraulic damper suitable for fitting to the Vincent Girdraulic forks. You can see more details of the front damper that Rob developed in conjunction with AVO at:
http://coventryvoc.co.uk/avo_front_damper_for_vincent.htm
http://coventryvoc.co.uk/avo_front_damper_for_vincent.htm
Thanks Ed,
I an behind anyone with an idea or theory to make something work better..... and put it into form and try it!
I an behind anyone with an idea or theory to make something work better..... and put it into form and try it!
I'll relate a few comments and cautions about the suspension peculiarities on our Vincents .
These are actual situations I've come across affecting handling characteristics , even introducing dangerous possibilities .
We had a nice looking C Rapide end up in being ours , it's owner fearful of it for reasons not understood . We soon learned it felt like it was going to throw the rider and itself down the road if the surface was rough . Weird and truly scary to ride . Turns out there was a poor choice of front damper and it's lower eye bolts causing the problem . also it had a funny snapping noise when power was rolled on , but first the handling quirk .
When the front wheel was raised off the floor allowing the forks to fully extend it was observed that the front fender rear section actually came in contact with the mag cowl hard enough to stop the fork from swinging across the center position
towards left or right . But why ? The fender and rear brace looked normal , what explained the contact ?
To do this the fork had to be going further down and so rearwards , but why .
I removed the front hyd. damper complete with the lower eye bolts FF 57 . The damper was a Koni , often found on Vincents and when compared with an original Vincent damper , both fully extended , it was seen that the Koni was longer . Then examining the eye bolts these were the later longer ones used on the D models with the Armstrong dampers . Could that be it ? you betcha ! Together they allowed the fork to extend further and so contact the cowl . Problem solved . I swapped out these parts with an original damper and the earlier eye bolts and handling was perfect .
Another odd thing about this Rapide was that it had odd snapping sound like the rear chain was jumping teeth . The sprockets and chain looked good , why the sound ? Tricky one this .
Pushing and pulling on the rear frame section revealed that the swing arm pivot boss had noticable side play between the G 50 plate and the left side plate FT 5 . Could that be it ? The rear section was removed and the bearings serviced , shimmed up snug and the end nuts E 80 were carefully shimmed beneath to be a boot
kick fit between the plates . Reassembled she rode and handled beautifully and the sound was gone . Quite like a new bike in all
aspects . More to follow focusing on the rear spring boxes and springs . These greatly enfluence handling would you believe ?
Sid .
These are actual situations I've come across affecting handling characteristics , even introducing dangerous possibilities .
We had a nice looking C Rapide end up in being ours , it's owner fearful of it for reasons not understood . We soon learned it felt like it was going to throw the rider and itself down the road if the surface was rough . Weird and truly scary to ride . Turns out there was a poor choice of front damper and it's lower eye bolts causing the problem . also it had a funny snapping noise when power was rolled on , but first the handling quirk .
When the front wheel was raised off the floor allowing the forks to fully extend it was observed that the front fender rear section actually came in contact with the mag cowl hard enough to stop the fork from swinging across the center position
towards left or right . But why ? The fender and rear brace looked normal , what explained the contact ?
To do this the fork had to be going further down and so rearwards , but why .
I removed the front hyd. damper complete with the lower eye bolts FF 57 . The damper was a Koni , often found on Vincents and when compared with an original Vincent damper , both fully extended , it was seen that the Koni was longer . Then examining the eye bolts these were the later longer ones used on the D models with the Armstrong dampers . Could that be it ? you betcha ! Together they allowed the fork to extend further and so contact the cowl . Problem solved . I swapped out these parts with an original damper and the earlier eye bolts and handling was perfect .
Another odd thing about this Rapide was that it had odd snapping sound like the rear chain was jumping teeth . The sprockets and chain looked good , why the sound ? Tricky one this .
Pushing and pulling on the rear frame section revealed that the swing arm pivot boss had noticable side play between the G 50 plate and the left side plate FT 5 . Could that be it ? The rear section was removed and the bearings serviced , shimmed up snug and the end nuts E 80 were carefully shimmed beneath to be a boot
kick fit between the plates . Reassembled she rode and handled beautifully and the sound was gone . Quite like a new bike in all
aspects . More to follow focusing on the rear spring boxes and springs . These greatly enfluence handling would you believe ?
Sid .
I know this is off subject but the Comet remarks prompted it . We have a 50 Meteor that goes so effortsly , tops the ton easily , a delightful handler with the Bramptons , a sweeter and smoother single is rare on this earth . It's been ported out to 32 mm right through , now on 8 to 1 with matching carb and manifold . Such a sweet and strong runner she is . Sid .
How fashions change (and bike vary)
long eye bolts were always de-rigure and its the first thing I make sure I have. If not I fit them. Back when computers were as big as a house it was alway quoted in MPH as supposedly a cure for tank slappers and I have never seen a mudguard near a cowl on my road bikes as for the racers I always fit them but for real handling Sids right Bramptons are the best
NB Koni ,standard and my own AVO damper (The Brampton has a special hydralic/spring unit)
long eye bolts were always de-rigure and its the first thing I make sure I have. If not I fit them. Back when computers were as big as a house it was alway quoted in MPH as supposedly a cure for tank slappers and I have never seen a mudguard near a cowl on my road bikes as for the racers I always fit them but for real handling Sids right Bramptons are the best
NB Koni ,standard and my own AVO damper (The Brampton has a special hydralic/spring unit)
Back on subject , suspension . My departed pal Ken Pettiford had the first longer rear springs made and these were superb , not too firm nor too long . Enough to easily carry a companion or a heavy load of luggage and give greater ground clearance too , yet retain a supple ride . He sent me an early set to try , report back , my weight and size a good test . All went beautifully with them .
A sweet guy , warm and friendly Ken had put huge mileage on his strong running Shadow . Was a pal also of my close friend Ed Leksa .
Back to the rear springs length effects upon handling . With longer springs the front forks are pulled in at the bottom so lessening the rake . With this subtle effect created by the top member, oil tank , now further forwards the altered fork angle feels lighter , the front end more flickable with less effort , the strength necessary reduced . Carried too far and the front end feels skittish , on the edge of a wobble perhaps from the reduced castor effect . Kens springs felt just right .
Even the standard original springs can be tweaked , particularly if sacked out shorter by extending the top and bottom eye bolts SP 4 a couple turns each . Check that the springs boxes are identical eye to eye on the bench before assembling on the bike . Also be sure the inner spring claws SP 1/1 are firmly engaged .
Sid .
A sweet guy , warm and friendly Ken had put huge mileage on his strong running Shadow . Was a pal also of my close friend Ed Leksa .
Back to the rear springs length effects upon handling . With longer springs the front forks are pulled in at the bottom so lessening the rake . With this subtle effect created by the top member, oil tank , now further forwards the altered fork angle feels lighter , the front end more flickable with less effort , the strength necessary reduced . Carried too far and the front end feels skittish , on the edge of a wobble perhaps from the reduced castor effect . Kens springs felt just right .
Even the standard original springs can be tweaked , particularly if sacked out shorter by extending the top and bottom eye bolts SP 4 a couple turns each . Check that the springs boxes are identical eye to eye on the bench before assembling on the bike . Also be sure the inner spring claws SP 1/1 are firmly engaged .
Sid .
Not exactly Vincent related but really important on a Vincati , the rear dampers on a Ducati GT 750 are very short and as a result the front forks are really raked out giving great directional stability but not easy bend swinging . Replacing these with a set of 13 inch eye to eye Konis offers lighter and more precise handling in the twisties . This decreases the rake by pulling in the front wheel , also giving more ground clearance beneath a Vincent twin motor . This is a trick widely used by those who raced these GT Ducatis .
Sid .
Sid .