The BSA A7-A10 Forum
Technical (Descriptive Topic Titles - Stay on Topic) => A7 & A10 Engine => Topic started by: trevinoz on 22.02. 2019 23:21
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Have a look at these new followers which have only done 500 miles in a newly rebuilt engine.
They are supposedly made in England and carry a brand on the packaging of a well known firm. Not "W" but "M".
The owner had been complaining about the engine being a bit rattly! Eventually the power dropped off markedly when the one of the followers was so badly worn that it hardly reached the camshaft.
He said that the cam appears to be OK.
I advised him to give the engine and oil tank a thorough clean. Probably the engine should be stripped down again but he said that the pistons seem to be OK and not badly scored.
I haven't seen the engine as the bike lives about 70 miles from me.
I can't imagine that there won't be a lot of damage done to the rest of the engine from the circulating steel slurry.
Bike is a 1951 Flash.
Apparently the followers failed the file test, soft as butter.
What do you think?
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Well, as long as you have the barrels off you might as well replace the followers. *whistle* *smile*
Richard L.
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Not good *pull hair out*
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Dear me! *eek*
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Message i'm getting from this is to keep all those old followers and get them Stellited and reground! Can't think who the 'M'' supplier is but has this been raised before on this forum?
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Well said, Ray. I am racking my brains....The only M I can think of is MCA of Aston, Birmingham, who, back in the day, were a well respected supplier. But, like Hepolite, a brand completely unrelated nowadays to their previous reputation, at least in the eyes of us oldies.
Snag here is that getting any sort of satisfaction will be difficult. For my money, Newman Cams in Farnborough, Kent is the place to get your bits. They are camshaft manufacturers and well versed in the foibles of vintage machinery. They can also reface, grind and harden your old worn genuine followers and work miracles on worn cams.
Trev...Very strange wear profiles. I would expect them all to be worn in the same way, or in pairs. The far edges are concave, as if the cam has been slopping sideways, allowing adjacent cams to contact both pairs of followers, then the major wear in one place, more to the foreground. Not as straightforward as it first appears.
Swarfy.
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They are supposedly made in England and carry a brand on the packaging of a well known firm. Not "W" but "M".
That's diabolical.
To protect the innocent and save the rest of us guessing, i think you should name and shame.
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More important that who made them is who sold them.
There is a lot of stuff on the web that was most likely rescued from the scrap bin ( do it myself ) .
Then I fall off my perch & they get sod into the market as NOS parts but not defective NOS parts.
Also another reason to test everything before fitting.
The folloers on the work SR 500 would go like that in about a week of riding once the paper thin hardening wore through.
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Hi guys, this is the M company that was with the pics, cheers
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Please do correct me if wrong but; my view is that the packaging isn't anything current ie it's an old box. Also, the writting and general condition suggests, at this distance from it, that the contents may not actually be related to it.
To add evidence of provenance, can we see the receipt etc for the purchase of them in this package?
There were followers available some years ago that were deemd to be rubbish and unsuitable but I'd be carefull reading too much into the context in which we see them now.
We've had a customer recently give us grief over a piston he bought from us. Having recently seen said piston...... we've never seen one like it nor stocked that brand! Mistakes do happen - says he from experience!
Paul.
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Here is a picture of my SRM supplied followers. I haven't sorted out the problem yet.
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We've had a customer recently give us grief over a piston he bought from us. Having recently seen said piston...... we've never seen one like it nor stocked that brand! Mistakes do happen - says he from experience!
Paul.
Are you a supplier of parts Paul?
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.....Trev...Very strange wear profiles. I would expect them all to be worn in the same way, or in pairs. The far edges are concave, as if the cam has been slopping sideways, allowing adjacent cams to contact both pairs of followers, then the major wear in one place, more to the foreground. Not as straightforward as it first appears....
Yes- very strange- maybe something to do with the order they engage/up& down *conf2*, but I'm inclined to think that the cam is not moving sideways, otherwise those bits at the edge of adjacent pairs would be all mashed too...when I rebuilt mine, I made a point of looking down the tunnel with the barrels on the cases and no lifters and the thrust flange hard up to the bush flange, just to ensure all is 'symmetrical' and the lifters don't clip adjacent lobes...all was well and with about the same spacing as in the pic
Can't explain the profiles at all *dunno*
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That MCA box and logo are the company that I mentioned. They are active now, with a nice website and contact details. Mr Google will find them easy. They are strictly wholesale, and have agents in NSW and Queensland.
That box and style look rather old. A phone number should start with the area code 0121, for Birmingham, England. If it starts 021, then the pack must be at least 25 years old, as the code changed. Are the followers originally from that SEALED box? Yes, the paperwork trail is all important.
GB... No progress, or just not got round to sorting? A closer look indicates only one inlet is wearing as if it was unhardened. The others are by no means as worn. Also the surface finish on the sides may be a clue to their source...looks speckled rather than a ground OEM finish.
duTch Looked as if they had started to wear on the far,raised edges, then the cam moved across to machine a deeper cut, with thecam located in place by the less worn raised edge. All very strange, different wear patterns on each.
Swarfy.
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GB... No progress, or just not got round to sorting? A closer look indicates only one inlet is wearing as if it was unhardened. The others are by no means as worn. Also the surface finish on the sides may be a clue to their source...looks speckled rather than a ground OEM finish.
No time, or drive, when I do have some time :(
They are SRM followers. SRM say they have seen this before and they feel sure the problem has been caused by bottoming. I'm beginning to suspect that I've fitted the wrong collets. I really must make the effort to sort the old girl; the weather is great for riding at the moment; 16° C with a clear blue sky!
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I recently purchased MCA A10 lifters from a trusted US source 6 months ago. When I opened the package (newer yellow MCA label), I knew right away something was not right about these. I've used many NOS A series lifters with a nice polished contact finish. The MCA's had a rough unfinished look. My engine builder did not want to use them. He did try to polish the wear surface the same way he finish polishes crank journals. He is now looking into having them treated. I hate to think what they would do to my NOS cam.
In defence of the supplier, I understand his predicament. You do your best to supply your customers needs and you don't have a way to test the product. This is where end user feedback is invaluable. MCA provides a needed service but must keep sight of protecting their reputation. I've had many reproduction parts on the shelf for years, only to discover their poor fit when the time came to use them.
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...The MCA's had a rough unfinished look....
My SRM supplied ones also have a sort of 'sintered' look to them. SRM assure me they are ok.
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yes greybeard srm supplied just like my bad piston rings, those followers of yours just shout out NO GOOD, the ones srm sold me have a super finish with srm lasered ? onto them.
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GB... This is for you.
An appeal by Swarfy in an attempt to cheer up esteemed member Greybeard. Also to get some traction on this cam follower problem.
GB reckons he has the wrong collets etc. May I request anyone with a head in bits to do some measuring, valve lengths, collet size, valve collet position, collet to valve tip distance? You know what I mean. A10, Iron Head. 1956. (so I reckon)
If you have a barrel to hand, how about the dimensions of a genuine follower. Could be these pattern repros are just a bit too long!
Lets help this fella a back on the road while there is still some gas left in the world!
Thank you all, fellow sufferers.
Swarfy.
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GB... This is for you.
An appeal by Swarfy in an attempt to cheer up esteemed member Greybeard. Also to get some traction on this cam follower problem.
GB reckons he has the wrong collets etc. May I request anyone with a head in bits to do some measuring, valve lengths, collet size, valve collet position, collet to valve tip distance? You know what I mean. A10, Iron Head. 1956. (so I reckon)
If you have a barrel to hand, how about the dimensions of a genuine follower. Could be these pattern repros are just a bit too long!
Lets help this fella a back on the road while there is still some gas left in the world!
Thank you all, fellow sufferers.
Swarfy.
Aw shucks! *red* *red* *red*
Thing is, I think my problems started after I changed the valve collets. I definitely had the wrong ones, (with a ridged inside edge) from yonks ago. I bought a set of wedge type collets, but I think I've read that there was more than one wedge type for these motors. SRM are positive that my problem is due to valve spring binding. I will compress the valve assemblies and check them when I can get enthusiastic about it.
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..... SRM say they have seen this before and they feel sure the problem has been caused by bottoming.........
Geebs, if you mean the lifter binding on the grub screws at full lift, maybe there should be 'witness marks' inside the travel stop zone ?
....I will compress the valve assemblies and check them when I can get enthusiastic about it......
At full lift, I guess you should be able to determine further travel by levering the rocker arm down a short amount (taking care to not lose the pushrod from the cup) ?
** edit- ^^ may be applicable as trevs' situation too *dunno*
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It's all a bit foggy in my memory at the moment. I will have to study everything when I get back to it.
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Further to this story, I was asked by the owner if I would rebuild his engine to which I agreed.
I stripped it down and inspected everything.
Amazingly the sludge from the followers did not wear anything out but it was caked heavily on the inner perimeter of the flywheel and had almost blocked the sludge trap.
There was no sign of wear on the big end journals, still on size from the grind and the camshaft was also in good nick.
The sludge was not easy to remove, it would not wash off in the tub without brushing but I am hopeful that it is all gone.
The crankcases are very early, dated January 1950 and do not have the oil feed to the cam trough and timing gears. I am curious as to when the oil feed was introduced.
There was a heavy deposit of carbon on the piston crowns and evidence of oil passing the Hepolite rings. I had the barrel coarsely honed and was informed by the machinist that the barrel had about 0.002 ovality and was a bit bell shaped, possibly caused by over heating.
The next problem was the valve adjusters, new when the engine was overhauled but worn out in 500 miles. They are very soft, I dressed them with a file and polished them, will try to harden them in the future.
I changed them for a used set I had to hand.
There were two left hand rods fitted to the engine so I blocked the oil hole on the one on the right.
The job is finished and the engine has gone home. Just waiting for the report on it when is back on the road.
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I believe this follower problem is that a lot of these sorts of parts are coming out of China - and often re-packaged. Trouble is, whilst we should be grateful there's parts available at all, my experience with Chinese metal working is that they haven't yet got the hang of hardening / tempering. Or even perhaps material choice. Just recently I had an hydraulic banjo bolt fail at 4,000psi (Chinese Honda look-alike) It had been over-hardended and was brittle as glass. The followers mentioned in this thread (including Greybeard's) clearly haven't been hardended properly - either too soft, skin too thin or base metal unable to support the loading involved. Cam followers are one of the most highly stressed parts of an engine.
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I agree RD fella my brother says the same as you regards the metal and heat treating, he has myford lathes and he bought a big Chinese lathe , he says everything is machined as soon as it comes out of the foundry but good old british castings were left to weather for years before they were machined --- bryon donkin valves for big industry comes to mind, here in chesterfield where a big donkin factory was the castings were all in the yards for many years, now its a case of quick production -time is money!! . He has done extensive work on the Chinese lathe to get it up to myford standard. going back to topic about the parts we sometimes have to throw in the bin the problem is with the packaging , if they put a union jack sticker on it or it says made in England on the box that is the con and apparently it is legal .
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I recently bought a Hepolite exhaust valve for a dbd34 and was surprised to find the tip was soft. Hepolite says that this is correct as a soft material against the hard rocker pad will lower wear. There's some logic to this, but why would BSA have specified hardened tips if not required ? Perhaps there is some modern thinking behind this theory, but I think I trust BSA more and made a hardened cap for the stem tip. Time will tell.
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wish I could talk to hepolite --- they don't exist anymore, and whoever told you that doesn't want the parts back . they just want sales, most things in this life now are cons and lies, they want your money, even a roads inspector told me that the person hole covers they put in are made in china and only last a couple of years before the frame distorts and they start banging. but it doesn't matter because its not the persons money who's buying them, its tax payers so it doesn't matter. if that was my valve I wouldn't be a happy bunny
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I believe this follower problem is that a lot of these sorts of parts are coming out of China - and often re-packaged. Trouble is, whilst we should be grateful there's parts available at all, my experience with Chinese metal working is that they haven't yet got the hang of hardening / tempering. Or even perhaps material choice. Just recently I had an hydraulic banjo bolt fail at 4,000psi (Chinese Honda look-alike) It had been over-hardended and was brittle as glass. The followers mentioned in this thread (including Greybeard's) clearly haven't been hardended properly - either too soft, skin too thin or base metal unable to support the loading involved. Cam followers are one of the most highly stressed parts of an engine.
Wrong.
They know exactly how to heat treat steel
However when Steptoe's son send one over to Ei Fool Yoo engineering with the instructions "make me 1000 that look exactly like these as cheaply as possible " that is exatly what the nice Mr Yoo does.
He make 1000 identical looking parts for 10p each.
Steptoes's son sells them to Ron Daily autos who then sells them a reputable parts wholesaler and finally you buy them for £ 20 each.
No factory owner in CHina goes looking for parts to make cheaply & badly.
They are all made for church going, Queen loving, patriotic Englishmen who ar the pillars of UK industry.
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BSA-54-A10
I understand what you say, but it actually reinforces my point - poor quality engineering is coming out of China. If Mr Ei Foo You was an engineer and wanted repeat business, he'd either make them properly or refuse the job. There is a difference between making as cheaply as possible (which is good engineering) and making poor or unsuitable quality - which is worse than bad engineering.
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Mr Ei Fool Yoo makes exactly what is specified - no more, no less. Blame the company's specifications, not the manufacturer.
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G'day,
Been pondering this cam follower hardness thing for a while now. :-\ Has anybody given an original un-molested follower the file test? I ask this because I have done this myself on 4 sets of original slightly worn ones on the un-worn part and all took a mark, not glass hard like the B&M engines as I expected. ( same with the cams)
I seem to remember reading somewhere that some cam & follower materials are not "glass hard" but made from a tough alloy steel. Does anyone know what material BSA made there A10/7 cam & followers from?
I know Notruns made there's from a low carbon case hardening steel & were very hard until someone re-ground them & didn't re-case harden properly (& subsequently only lasted a few weeks) .
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Never had the courage to do this, but in the past have stoned small grooves and scuffs from cam lobes.
Back in the day, Ford Pinto engines suffered from cam and follower wear. The followers always wore more, and if you were aware of a problem, it was an easy fix if you caught it early. The expensive cure was a new cam and followers, but for European Engines the cam came out through the back of the head, so it was head off, or engine out, or a hole in the bulkhead. The cheapskate cure was a new set of followers and removal of the wear ridges by hand stoning the cam in situ. A new, clean and free flowing oil supply rail completed the job, and you were back on the road for a good while. The design was different for US motors, the cam came out through the front.
The performance difference after this codge was marginal, but the motors were restored to smooth unobtrusive running, even for a Ford. Remember these were real cheap clunkers, by the time I got them, and a noisy cam was a good bargaining chip when negotiating the deal.
The metallurgy was fine, failure was all down to extended oil changes and blocking of the oil supply rail with carbonised oil.
Wear starts as straight line across the follower, as the greatest load is always concentrated in one place. Once through the hardening, its like a pothole....clunk clunk, getting bigger and deeper. On the cam, the contact load is spread over a larger area and maximum load only occurs on the toe for a short time in comparison, hence the differing rates of wear.
I do not know if cams and followers are hardened to identical standards..any cam grinders on the forum?
Swarfy
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Over 20 years ago when I restored my first 1957 A10 I polished out some marks on the cam followers but when I got the bike on the road they only lasted a few months I took them out and took them to a Guy who was giving me help and advice he said that what I had done was polish through the hardened layer on the surface of the followers thus exposing the softer metal underneath, he sent them away for me and they were built up and reprofiled they were still on the bike when I sold it 16 years later. So rather than buy new ones which could be sub standard if I was faced with worn followers I would look to having the originals rebuilt and reprofiled assuming that I coould find a company to do it.
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in the shed today- not the pub, so i got a smooth file and ran it over a ball race in several places , under a decent magnifying glass I could see little scratches but couldn't dig the file in. then I got some old followers and did the same in several places including the inside slots. I got the same result, then on a part worn camshaft , by worn I mean about 4thou worn and could just dig the file in on the worn lobes using a lot of force but not on the shaft, only got scratches there. anyway if you've got cams or followers that a file doesn't glide over like on a ball race you might as well scream and throw them over your shoulder *pull hair out*
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Hi All,
My SR has rebuilt stellite faced followers fitted , this was done back in 94/5 by SRM
They have been fine,
On the last A10 I built about 3 years ago I got some new followers, again they were stellite faced
I polished up the cam surfaces with a fine hone stone
A current engine on the bench is a BSA 350 from 1924, the followers are a bit manky *eek*
The plan is to regirind the profile and test for hardness, then make a decision as to "what to do next" if they are soft
Works for me
John
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stellite is only the trade name but the mix of chrome alloys is a very good anti wear surface, just like platinum tipped points on spitfires , treated my maggy to a set of platinum tipped points, but going back to the dimple looking marked followers I don't think they are any good for any engine
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I bought some rods marked Stellite and used one on my fury rockers. Seemed to flow like a braze using brazing flux. I was surprised how easy it was to profile (thought it would be much harder) and didn't have much hope of success, but in ten years have had to further problems. Perhaps Stellite work hardens in use ?
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never known of it work hardening like some stainless does, but it holds its properties at high temperature as in your welding , did you grind it for the finish off, it has a few properties like chromium and cobalt including a bit of carbon and is very good anti wear material *good3* been around for donky's years and years and many more years
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Hi All,
My SR has rebuilt stellite faced followers fitted , this was done back in 94/5 by SRM
They have been fine,
On the last A10 I built about 3 years ago I got some new followers, again they were stellite faced
I polished up the cam surfaces with a fine hone stone
A current engine on the bench is a BSA 350 from 1924, the followers are a bit manky *eek*
The plan is to regirind the profile and test for hardness, then make a decision as to "what to do next" if they are soft
Works for me
John
So the next Cannonball attempt will be on a model L will it ?
OHV or SV ?
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Hi Trevor,
Its an ohv
I bought it as a rough runner a few years ago
Again it's been a long road to repair before restoring it
There's a couple in the Czech republic that make fantastic replica parts which has been a great help
As for the Cannonball 2020 ???
I do not know if my "sponsor" is up to trying it again
John
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Hi Trevor,
Its an ohv
I bought it as a rough runner a few years ago
Again it's been a long road to repair before restoring it
There's a couple in the Czech republic that make fantastic replica parts which has been a great help
As for the Cannonball 2020 ???
I do not know if my "sponsor" is up to trying it again
John
That's interesting.
The landlord has a pair of L's one of each kind ( sloper excluded ) and is looking for a few parts, and a tank for the SV in particular.
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Hi Trevor,
There are at least 3 different types of
Flat tank for the L models
Jules Dassen in Holland has had a few replica tanks made, a friend bought one but it did not fit his 24 at all!!!
And the 27 has a much more sloped back end
Again reference to the parts book needed
John
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About the cam followers, all I can say is I bought a new set back in 2017 - because our engineer advised my old ones were too worn. I bought them from British Spares, Austria - because they said theirs were stellite-tipped. Our engineer said "they weren't" but did the hardness test - with his set of little files of different hardness. They passed. That's about 3.5k miles ago. No sign of wearing. My tappets don't get looser (more the reverse, occasionally). I just hope I've been lucky with these followers, then. They were too tight at first, and he fettled them to a good sliding fit, also. I also use Penrite Enduro - because of its high zinc content. Our engineer was particular about the zinc, necessary for preventing cam-follower wear..
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Hi Trevor,
There are at least 3 different types of
Flat tank for the L models
Jules Dassen in Holland has had a few replica tanks made, a friend bought one but it did not fit his 24 at all!!!
And the 27 has a much more sloped back end
Again reference to the parts book needed
John
Yes have already found that one out.
One thank s good the other is a blob of fiberglass with some original fittings in almost the right places.
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Hi Brit
I'm going w/- Swarf on this one, about 50 years ago we did an engine up (S/rocket) and were given the wrong head parts at the motorbike parts shop, I think it was the valves , they had the collet grooves in a different ( lower ) position and springs were binding and that wore the follower's out in about a week
Barry
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Similar to GB's problem where SR valves with A10 cotters or vice versa.
Cheers
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Hi Brit
I'm going w/- Swarf on this one, about 50 years ago we did an engine up (S/rocket) and were given the wrong head parts at the motorbike parts shop, I think it was the valves , they had the collet grooves in a different ( lower ) position and springs were binding and that wore the follower's out in about a week
Barry
Now that sounds a very likely scenario for my buggered followers!