Speedo calibration?

H

Henry Martini

Well Known and Active Forum User
Non-VOC Member
Hi Eric,
For what it's worth many years ago I got a speedo expert to calibrate my 5 inch speedo this he did in that the speed shown by the needle was made very accurate but he told me that it was
not possible to correct the mileometer as it was driven by gears and was fixed,so at best only your indicated speed will take adjustment. Unless it is possible to get various gear ratios.

Henry Martini
 
ossie

ossie

Well Known and Active Forum User
VOC Member
aren,t american miles shorter than english ones so it will never be right will it????
OSSIE
 
nkt267

nkt267

Well Known and Active Forum User
VOC Member
aren,t american miles shorter than english ones so it will never be right will it????
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Now get it right ..Everything in America is BIGGER and BETTER than anywhere else in the world so their miles are longer so when you've done 60 miles on your Imperial Vincent speedo you've only gone 50 colonial miles.Therefore your speedo must be reading fast..:D John
 
H

Henry Martini

Well Known and Active Forum User
Non-VOC Member
Hi Trev,
I certainly do and was reminded about the French event only last Saturday when I had a rear wheel instantly deflate due
to the valve neck detaching from the tube, Doing 60 mph at the time on a dual carriage way, and needed both before stopping.
I must have been doing 75 mph that night in France when the entire 2 piece Rukka suit got pulled into the rear wheel,George
Brown or Alf Hagon would have been proud of the long black layer of rubber I left on that small narrow French road.I think I
still owe you and a large team of VOC members a keg of Guinness for rebuilding the rear end of my bike. What Year French
Rally was that.
Regards, Henry
 
H

Henry Martini

Well Known and Active Forum User
Non-VOC Member
bmetcalf;[ said:
What brand of tube was it?
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Hi Bruce,It was a Continental real rubber made in India, I don't like the Chinese plastic ones as they don't take a patch very well.
Having said that I don't believe in patching tubes except just to get you home. I don't have security bolts fitted perhaps,I should
consider fitting them.Both Tyre and tube were new and fitted to a new stainless rim 400 miles ago. I should have done the fitting
myself !!!

Henry
 
b'knighted

b'knighted

Well Known and Active Forum User
VOC Member
bmetcalf said:
What steps did you take to do that?
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I bought a damaged Honda VF750 Sabre 18" cast front wheel from my local wreckers. This was in the eighties so they were more common than they are now. The bearings had broken out of it but its disc mounting pads were perfect. I had access to a serious lathe and by removing the lump of bed from its gap was able to set the wheel up accurately on a four jaw chuck. My recollection is that it was within a few thou. of true. I cannot remember which was centre and which was face but the figures of 0.0040 and 0.0015 stick in my mind. I bored out the broken bearing housings and with a roughly cut disk of inch thick ally bolted on to the disc pads turned it true and bored it. A "top hat" was turned from 3" ally bar and with the plate removed was pressed through its bore so that the flange was sandwiched between the wheel and the plate once refitted.
This top hat was then bored concentric. Being daft I removed the wheel and did the same on the other side instead of just making a second plate and centre boss while the wheel was mounted. I lost the job and, access to the lathe but as I had also seized my big end at the time it became less important. When the time came for a rebuild some years later, my VOC mentor, Roger Clark finished the machining of the bolt on assemblies to take Vincent bearings and run on a Vincent hollow axle. The plate on the righthand side is machined the correct thickness to align a ¼ sprocket and Roger champhered the left plate to match the back of a Vincent drum which uses a steel brake plate tight to the inside of the RFM. This wheel has been in use for all of this century and has carried a variety of tubeless tyres. It is currently fitted with an Avon Distanzia as is the tubed 19" front wheel. With it hidden under the rear cowl it gets a bit neglected and has suffered a bit of salt corrosion. Ebay has recently provided me with a hardly used identical wheel which will fit between my plates when the bead no longer seals well enough to holds air.

Look closely at my avatar to see the lack of rear spokes.

I fancy tubeless tyres on my big Comet and have been looking at the big BMW trailie wheels that have straight spokes running from a wide land out board of the rim. The fronts have dual discs which should permit Vincent bearing carriers to be fitted but I'm not sure that the 18" or 19" are narrow enough to fit alongside the chain.

See http://www.ebay.co.uk/itm/BMW-R1200...31?pt=UK_Motorcycle_Parts&hash=item35c379aaf7 for spoke style. A bit too expensive for me to chop up at the moment.
 
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