No reason at all why it should not work, for a number of years now I`ve been fitting one of those into the layshaft bearing in the timing case. It takes a heavier load than the ball it replaces, as nowadays there are less balls used than the original, and the modern variety just do not last, first gear sorts them out.
ET77 Main bearing distance piece
- Thread starter craig
- Start date
Hi, T T , that,s an elegant solution to the problem, but if you can't do it yourself it sounds expensive ! Just glad I went for new parts to make a start, Regards, Roy.
I've been out of the bearing trade for a few years, so I'm a bit rusty. I think the dot system was pre metric marking. The internal clearance rating is now shown with a C - CN is normal clearance, C2 is tighter fitting, C3 (3 spot equivalent), C4, C5 ... have a bigger clearance. It's nothing to do with the tolerance of the outside of the bearing, it's a measure of how slack the balls/rollers are (if you see what I mean). If you fit the bearing on a tight shaft or in a tight bore, it squeeses the bearing and reduces the internal clearance, and if you run hot and fast it also reduces the clearance. A Vin main bearing would be an obvious C3 choice, fitting a CN or tighter could cause problems............. but if we're saying all Vin cases and shafts are worn out with loose bearings, maybe we should use CN nowadays.
As for "was he having you on?" A lot of bearing suppliers' employees aren't engineers and give an opinion based on there (lack of) engineering knowledge, without knowing your supplier, I would suspect he was advising based on his limited knowledge and we all know a little knowledge is......................
H
ps the the loose bearing comment part is tongue in cheek!
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Read, Brother, Read
The bearing has nothing to do with it. Why would Phill Irving show you how to correct worn alloy cases in " Tuning for Speed" if he didn't think it vital? You'ze guys are still trying to fit fit a round peg in a square hole.
The bearing has nothing to do with it. Why would Phill Irving show you how to correct worn alloy cases in " Tuning for Speed" if he didn't think it vital? You'ze guys are still trying to fit fit a round peg in a square hole.
Tuning for speed says IF the cases are worn tin or plate the bearings or "Loctite can be used effectively". "IF the wear is very great, a permanent cure can be effected by boring the housing ............" It doesn't say always line bore the cases and sleeve them when fitting new bearings.
If the bearing is a good fit in the case it shouldn't turn, if it doesn't turn, it won't wear the cases, if it doesn't wear the cases why sleeve them?
If you're going for 200mph at Bonneville then strip the engine and make it "perfect", but 70 mph on British motorways is well inside the 2 Phils original design brief.
H
If the bearing is a good fit in the case it shouldn't turn, if it doesn't turn, it won't wear the cases, if it doesn't wear the cases why sleeve them?
If you're going for 200mph at Bonneville then strip the engine and make it "perfect", but 70 mph on British motorways is well inside the 2 Phils original design brief.
H
The Main bearing should have been the same as an " A " But that's Progress !! Cheers Bill.
I have not always sleeved myself.... we are talking about the degree of wear here.... if the bearing has just become loose and the bore measures true and round and has not been loose so long that
it has been pounded wayyyyy out of round and really,really loose you can get away with loctite, mechanical, retainers, and a low radial clearance bearing as there is no shrink fit to compress the race
to it's proper dimension. And you are right in considering how the machine is going to be used. Again, I enjoyed doing things the best way I could .... and a fella can do things anyway he wants to his own
machine. But, if a machine were brought to me for a total rebuild this is what I did. I have had plenty of situations were a fellow just didn't want or could not afford this work and I would do what I could
to keep him running.
it has been pounded wayyyyy out of round and really,really loose you can get away with loctite, mechanical, retainers, and a low radial clearance bearing as there is no shrink fit to compress the race
to it's proper dimension. And you are right in considering how the machine is going to be used. Again, I enjoyed doing things the best way I could .... and a fella can do things anyway he wants to his own
machine. But, if a machine were brought to me for a total rebuild this is what I did. I have had plenty of situations were a fellow just didn't want or could not afford this work and I would do what I could
to keep him running.
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On big end bearings . It seems that INA cages were used in recent years also by ALPHA but these German made bearing assemblies have dried up . Prince used them as well I think while available . Not aware of what is available at the moment .
I'd accept what DavidD says as he is a racer to his boot straps and keeps right up with whats current and best . No doubt about his knowledge being cutting edge .
The Works used alloy cages with tripple quarter by quarter inch rollers , three in each slot . Proved on the Picador and fitted to all Black Lightnings . Together with Vibrac rods this was the top setup , and this big end along with a double speed pump worm gives excellent service for racing and fast road work . It was used in my drag bike for several years of regular racing , and before that for fast street riding over a large mileage without any bother or replacements . Sid .
I'd accept what DavidD says as he is a racer to his boot straps and keeps right up with whats current and best . No doubt about his knowledge being cutting edge .
The Works used alloy cages with tripple quarter by quarter inch rollers , three in each slot . Proved on the Picador and fitted to all Black Lightnings . Together with Vibrac rods this was the top setup , and this big end along with a double speed pump worm gives excellent service for racing and fast road work . It was used in my drag bike for several years of regular racing , and before that for fast street riding over a large mileage without any bother or replacements . Sid .
As so often pointed out every Vincent , particularly with considerable mileage on it enc. occasional drag starts , high revs etc is uniquely different . And needs after close study and pondering attention suitable to access its needs . More serious maintenance than what we call a full restoration . This is a riders bike , not a posers machine or seeking the highest market value . The owner wants it ready for the road and with assurance that he can expect performance and reliability on the order of that delivered 50/60 years ago . Not today's OOooos and AAaasesss from the crowd of onlookers it draws today . He's a Vincent man , proud of what it delivers on the road and how it makes him feel when riding it . Thats the way it was way back then . Sid .