Girdraulics: are they safe?

[Albervin]

I bought my first Vincent in 1985 & it was a load of rubbish. Of course I didn't know it then as I was ignorant of all things Vincent. I bought the bike from a reputable dealer (Atlantic Motorcycles) & spoke to the previous owner of the bike (Ted Davis) who assured me it was a good bike. The fork bushes were worn & only half bushes inserted in some places. I ended up on my head with a broken shoulder, dislocated knee & a lot of bruising. If I had had the time & money I would have sued both parties for selling something not fit for purpose. Now I just tell everyone the truth. Well sorted girdraulics are safe & pleasant to ride BUT you must know what you are doing before you lift a spanner to them. Tyre types & pressures probably affect handling more than they would with telescopic forks but then a Vincent is like some women I have known, plenty of TLC is well rewarded! Given the choice though, I prefer my Brampton forked Vincents...

 

[Bill Thomas]

To Tnecniv Edipar,
Please read. The Votes are wrong,The first bloke to vote pressed the wrong button !!When I got hurt it was on the track, the vote says on the road, In letter 4. I said sorry but nobody has changed it, To see who voted what go to home page then results.
So that means it's just poor John998 and tonythecat my thoughts go with you .
I am just about to get my Standard fork Twin out,Wish me luck.
All the best Bill.

 

[Tnecniv Edipar]

Only 39 responses out of how many readers? Can Graham tell us?

734 had read the thread when I looked a minute or so ago. No poll will ever be perfect or fully representative , I just wanted a general idea of how Girdraulics are in reality not just myth. Over 80% of votes so far say they are fine.

 

[Tnecniv Edipar]

All possibly true , but if they genuinely had a reputation for killing riders or even injuring or putting lives at serious risk then it would probably be more than just a rumour.

Many early Jap bikes had a widowmaker reputation and it was totally deserved !! I've ridden CB750's and Kawasaki Triples that were dire !! And it wasn't just handling , tyres and brakes were heart stoppingly bad in the wet and definitely DID kill people.

I remember an incident many years ago when I was 'on a mission' on my '69 Bonny on some entertaining roads in West Yorkshire and overtook a Suzuki 750 triple. The rider decided that British scrap (his words) was not going to humiliate his Jap wonder bike so came back past me , on a long straight ! After this straight there was a series of bends that shall we say 'get your attention' ! I easily out braked him into the first bend as he quickly realised he was running out of road. After half a mile or so he wasn't even a spec in my mirrors. Half an hour later I was riding through Wetherby and he rode up along side me at some lights. He asked me to pull over for a chat. We had an entertaining chat for half an hour where he said I must be a lunatic to go through bends at that speed on that pile of British scrap !! The Bonny had no idea it was such a lowly heap and it didn't seem to be trying that hard.
However , I do recall it had a steering shimmy at around 30 MPH with no hands on the bars !!!

 

[john998]

Girdraulics

Hello,
Nulli Secundus has it right if everything works against you are off. The forces generated are so great that I doubt even a hydraulic searing damper will stop you being ejected.
On my first event I was pitched over the bars so hard that I hit the road in a riding position. wearing holes in knees and elbows. At that time (1968) my machine would have been some what worn as an apprentices wage did not go far.
Stories of very well maintained machines suffering wobbles do exist, but I think then much less common.
My cure is simple do as I did, fit Bramptons, 40 years on no problems.
In some of the very first MPHs people where discusing wobbles so nothing changes. John.

 

[Bracker1]

I don't think any suspension is safe if not properly serviced and set up . Poor maintenance, poor riding shouldn't condemn a particular design.

No living pilot is likely to jump into his plane without inspecting and correcting any problems. A motorcycle should be treated as such.

My one concern is the age of the alloy blades and their fatigue due to use and abuse. Has anyone had failure of the girdraulic from fracture, and if so had the bike been in an accident? I would think at some point they could be examined for stress fractures, but have no idea how.
Safe riding, Dan

 

[john998]

Girdraulics

Hello Dave,
Some time before my wobble playing silly Bs in the snow, I hit what I though was a pile of snow that turn out to be solid ice. The front wheel was deflected to full lock and yet no wobble developed from that. This was at relatively low speed due to the road conditions.
When I had the big wobble shortly after, I was accelerating through about 50 mph in a straight line over a small bridge.It was so quick that I thought I had hit something on the road, but there was nothing to hit.
Bramtons are great for a solo. John.

 

[vince998]

This poll is my instigation , Graham posted it up for me as members cannot.
Just wanted to have a go at clearing up this apparent doubt over the integrity of Girdraulic forks. With the voting as it stands it seems they have an overwhelming vindication. Personally I never had any doubt whatsoever , the negative stories I've heard and seen over the years I've put down to bad maintenance , assembly , neglect , damage or wear.

I suppose the only issue remaining is to determine how often they should be inspected for wear and what wear constitutes as unacceptable.

I ride all types of roads (and not always in adherence to the German speed limits), and for the last 16 months i´m forced to ride badly maintained B roads (with lots of corners/inclines/dips,so i don´t mind) and i´ve never had even an inclination of a wobble since i´ve owned the bike. (If the tyre doesn´t run 100% true which appears quite often with the "new" roadrunners, only then when you let go of the bars. Please, don´t ask, must have something to do with the voices)

Mines a D shadow with fairly soft springs, and fairly new koni damper.
I believe the reason i´ve not had a problem (i only started using the steering damper after reading this forum ) is down to the sprung/unsprung weight of the machine in question.
Sprung weight= lots of stainless, and i´m not getting any thinner (the forks/springs don´t really spend much time fully unloaded so the bike doesn´t "ride over the forks". Unsprung weight= rims and spokes are stainless as well as all fittings (so taking a lot more energy to get everything moving)

Maybe if the guys who have had near misses or spills could say if they had undertaken any weight saving measures i.e alloy rims etc when this occured?
This would really help to make sense of the "wobblers" amongst us.
As the poll stands at the moment,it seems pretty hit and miss, and i´m waiting for it to happen at any moment, and this is almost certainly not helping the cause

Worn forks could maybe contribute to amplifying a wobble, but i don´t think this is the real instigator(unless really worn, like 1/4" play left and right worn!!). A mixture of extended forks (shortened wheelbase along with steepened steering angle? (are both links the same length?) in conjunction with a reduced resistance to external energy inputs/absorbtion (unsprung weight)

An exception to this is maybe russel on his D (because he likes things firm and fruity). I believe he also had an experience of the "wobbly kind", and this really got me thinking. (when "himself at the source of all things well fitting and shiney" can have a problem (and that on the ultimate of all vincent machines - A SERIES "D") then it´s only a matter of time before it gets me to?

 

[peterg]

Girdraulics - a life saver

Howdy Chaps,

This one's very fresh on my mind. 3 wks ago I experienced my first rapid front tire deflation on a street machine after 38 years on the road. We were two up in a series of bends through a forest lane with no runoff. Thankfully it involved a 3.0 x 20 which resulted minimal drop distance to the rim or rubber flailing about. But, I will say this. As an avid weightlifter the forces unleashed at the helm were incomprehensible compared to any I'd ever experienced after years on dirt bikes. The final scrubbing off of speed by literally standing up with my feet sliding on the pavement as outriggers while hoisting the front of the machine aloft bent both handlebar ends upward.

But, what will forever stand in my mind was the ability to control the machine down to the point where I could get my feet to the pavement. There was positively no fork blade whip to rob one of life preserving feel and control of wheel direction. My countersteering pressure against these immense opposing forces would have buckled any telescopic assembly, turning its flexing fork tubes into springs only adding to my dire situation.

And for this, I will be forever gratefull that this hoped-for single event occured on this very machine. My wife and I would have been seriously injured, or worse, on nearly anything else.

 

[Bracker1]

One last note on girdraulics. If I am not mistaken, the world record holder for true motorcycles, Dave Matson , used girdraulics on his machine. They must world pretty well if he went over 230 MPH. Cheers, Dan