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Struggling to recommission R60

EuroIron
Posts: 367
Joined: Mon Apr 23, 2007 12:38 pm

Struggling to recommission R60

Post by EuroIron »

overheating in the pipes is very typical of erratic marginal ignition

pipe loads up with raw gas and then maybe the mag finds enough reserve and rise time to cut thru the fouling and light that cylinder off.......

seen them glow nuke red before

Allan.Atherton
Posts: 503
Joined: Fri Oct 27, 2006 3:00 am

Struggling to recommission R60

Post by Allan.Atherton »

... a good A&P at a smaller airport can refresh that rotor in just a minute or so...
I left my rotor to the local airport, and a week later they gave it back saying it was a permanent magnet so could not be recharged.
I asked Ed Lipe in FL who rewinds coils, and he said only pre-war rotors could be recharged.
I heard from Randy Franks that rotors can be re-charged, or rather super charged to a higher state of magnetism, but the rotor will quickly revert to regular strength unless rotor is kept in a steel holder while out of the magneto body.

EuroIron
Posts: 367
Joined: Mon Apr 23, 2007 12:38 pm

Struggling to recommission R60

Post by EuroIron »

"rather super charged to a higher state of magnetism, but the rotor will quickly revert to regular strength unless rotor is kept in a steel holder while out of the magneto body."


fitted to the bike with the magneto's Mu metal around it works well but to properly store one out of the magneto itself...... should be done with some curved clamshells

they live much longer that way

and yes permanent magnet rotors for most anything can be regaussed

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niall4473
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Struggling to recommission R60

Post by niall4473 »

Hi all,
Thanks a lot to everybody who replied, and to anybody who even thought about it.
Just reread the whole thread, and I think I might have spotted where I went wrong, stand by for a report in about 2 days time!

Cheers and thanks again.
Oil is always cheaper than metal

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niall4473
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Struggling to recommission R60

Post by niall4473 »

Thanks again to all who replied.
Well the bike is now running running as sweet as a nut, but I'm afraid I can't really throw any light on what the problem was, except that it was ignition related as I thought from day one, because I solved the problem by fitting an MZ-b unit and now the bike is running fine.
I can only assume that somehow one pickup was robbing the other, but as to how I can't say as I believe these are actually two separate coils wound around a common iron core, or why changing every single component in the ignition system (more than once), did not make a difference to it. Perhaps after 30 years in the family the bike didn't want to be sold, but the old man is winding things down and I couldn't possibly keep them all, (sigh!), so it has been and will be going to its new home shortly, at least its gone it a friend of mine who I know will look after it. Yes I know its not standard, its a bike for riding, but when I first saw this bike it had car rims on it.....

Image

Next one up will be another interesting bike, an R67/R60 hybrid with /5 rear suspension, will post a picture when I get it to my house.
Thanks again.
Oil is always cheaper than metal

EuroIron
Posts: 367
Joined: Mon Apr 23, 2007 12:38 pm

Struggling to recommission R60

Post by EuroIron »

excellent you got it running by replacing the magneto with a complete ignition unit?

the stock magneto's coil is a simple transformer which is not center tapped or polarity conscience


so any weakness....... in the coil or flux generated by a weak rotor....... can affect either or both cylinders and at low speed........ it can tend to favor the cylinder of least efficiency...... ie lower compression and path of least resistance....... so such problems can be aggrevating to diagnose

the stock coils go bad as the varnish over their windings deteriorates thru the years

there are modern bolt in replacements

very possible you had both a weak rotor and weak coil and likely would have found no success putting in a modern good coil without a regausss

nice looking ride......... did you say car rims? have any pix of that setup or even the rims now off the bike?

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niall4473
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Struggling to recommission R60

Post by niall4473 »

Hi EuroIron,
Sorry for not replying sooner but I've been away working in Northern Ireland, and there was no public internet where I was.

did you say car rims? have any pix of that setup or even the rims now off the bike?

No, unfortunately, because it was one of the ugliest things I've ever seen, obviously it had been converted into a lowline outfit, probably not for racing because the things weighed a ton and were only about 4.50 section, (15 inch diameter), in the same job lot that was brought over from Germany there was an R50S motor with the left hand cylinder smashed off and a badly damaged Hoske tank, one of the rims, presumably the front one was badly bent so those bits probably had been together, and wrapped up in an accident. Someone had started to rebuild it using this bike as a donor, just as well they gave up, it must have had all the ground clearance of a slug.
The wheels themselves were very crude, they weren't wire wheels like off an MG or whatever, they were dished pressed ones off some kind of 1950's German car or small van and were BOLTED directly to studs drilled through the cast iron part of the hub and located with taper seat nuts, I personally would not have gone down to the shops on it.
This was back in about 1975.
Oil is always cheaper than metal

vonkas
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Joined: Wed Nov 29, 2006 6:37 am

Re: Struggling to recommission R60

Post by vonkas »

I'm scratching my head with this R60, trying to recommission it after a long period of storage. ...

could be the 'break off' of the magneto is exceeded as soon as the auto advance starts moving. To test for this, lock the weights into place (cable tie). If it then runs a bit better you found the culprit. I have german instructions how to align it properly and there is a not so obvious pre-condition - but do the testfirst..

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VBMWMO
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Struggling to recommission R60

Post by VBMWMO »

I'm scratching my head with this R60, trying to recommission it after a long period of storage. The bike was rebuilt about 5 years ago and not used. I've done all the things you do in this case, change all oils, oil cables, flush tank etc, even though the bike was properly laid up with all fresh oil, tyres up etc.
The thing is it will only run on one pot at anything above idle, it will tick over all day, steady as you like, and carry on with either HT lead off but it will not take throttle, sometimes the no.1 cylinder runs, sometimes No.2 and the running cylinder gets very hot (spitbouncing hot). Compression is ok, 8bar No1, 8.5bar No.2, valve clearances 0.15mm inlet, 0.2mm exhaust. I've tried changing the mag coil (twice), the whole mag including advance/retard(3 times), timing is bob on, the points let go a fagpaper bang on the S mark, dot and dash of the rotor right in the vee notch. Also the plugs, caps, HT leads, condenser all replaced, no difference. I've had the pipes off, no bird nests or rags blocking them. The valves are opening and closing both sides, tried (new)air filter in/out, air tubes on/off, no difference.
The carbs are the late type big mixing chamber, lever top float bowl ones, nothing blocked I can find, in any case tried two other sets of carbs one early R60, one R67/2, not expecting it to run perfect, just make a change but it is EXACTLY the same.
Fuel is 96 octane leaded, and its fresh.
Anyone got any fresh ideas please, because I'm running out, and the only thing I can think of left to check is valve timing, but I can't see that being the problem because its common to both cylinders.
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