Petteford rear springs

timetraveller

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Which is why a lot of serious competitors do not use a brake drum to take the stresses of a chain but rather use an aluminium disk as a rear sprocket carrier.
 

Big Sid

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Sid here . Way ahead of you . My dragster had this arrangement back in the late 50s . Returning to it now .
 

clevtrev

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I forgot to mention, the three points, engine sprocket, pivot and rear chain sprocket, do not come into line until the lower member of the rear frame is approximately 2 degrees higher at the rear, and the first inch of deflection moves the sprockets .005" closer together, and so on.

Failed to factor in the height of the axle above the frame rail line.
 
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clevtrev

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Never experienced rapid chain and sprocket wear over my ownership since 1951 , must have gotten it right . Had them eaten up by Bonneville salt tho ! You should try it . Sid .
My bike has lived surrounded by the sea for fifty years, not just a once in a lifetime trip to the salt. You learn to keep the bike well oiled, inside and out. If you care to bring a bike over for a ride on our roads through the winter,you`ll find the same results as you found after Bonneville, and quite a few riders do it, so don`t think you are unique.
 

Big Sid

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Sid here with a couple of remarks . At Bonneville it rained every evening beginning around 5 pm so the salt was wet every morning . The winds would kick up blowing this damp shite from every direction , taking down tents , blowing over bikes . And at speed it was flung up in a grey shower over everything off both tires , the undersides of fenders are packed with the stuff likewise the bottom of the cases , and the magneto is stuffed in every crevice . Its very sticky and packs up hard . There is NO place on Earth quite like those conditions no matter what Trev thinks . And the corrosion begins immediately to consume nearly everything .
Been in England , longest leave there was 32 days , saw the rain and damp , nothing like Bonneville . A drenched bike and rider , muddy tires and boots for sure . Saw no salt in the wind .
Rather like I often saw in Norfolk Va living near the Bay and the Atlantic ocean .
Back to rear chain lash . With several different rear springs in use , often sacked out there is no set length nor swing arm angle as a constant thus the free play figures vary over a range , rarely identical between two Vincent's . So it seems to me .
 

mercurycrest

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I raced at Bonneville maybe a dozen times. It doesn't take a Rocket Scientist to figure out he needs to cover the ignition with rags and duct tape to keep the salt out and then use lots of hose pipe water when you get home to cleans out the rest... chains, fenders, trucks/vans/trailers etc... My Race Bike sat ten years and it's still like new. Last year, I rode the 350 Bullet out in brine deep enough it cover the foot pegs........ The one casualty was the carb and only then, because I was dumb enough to clean it in a vinegar solution and melted all the zinc junk in the carb.
Cheers, John
 

vibrac

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Not there in the Winter and it was in 53 . Sid .
no salt needed in the 50's back then people who used the roads knew what to do when it was icy and trains did not stop for the wrong type of snow
only sand needed was under the wheels of the flying scotsman from tubes set there when designed. and a sack of the stuff in the back of the car boot or in the sidecar
Salt? another scheme of Mr money grabbing 'Motorway' Marples and his side kick 'Railway killing' Beeching

here is what I mean no salt here and not many gloves http://www.youtube.com/watch?v=-ugIoMD495E
 
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Bill Thomas

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Hello John, I read you have a BIG twin, Did you ever run it at Bonneville ? Did it go well, Any details, Cheers Bill.
 
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