magneto inspection with modified cover

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I wanted to chase down an ignition miss so I cut a spare cover in 1/2 for a test. Now I can wear magnification and clearly see if there is any shorting between the wires. What I saw was a lot of electrical flame arcing because of dirty points. I used a diamond grit abrasive to clean the points and problem solved (much less arching). You might be able to achieve the same with a clear cover but I wanted the clearest view possible. I use a connector to make changing the condenser easier.

magneto inspection with modified cover



Has any one used the "easy cap" shown in the link below? Any advantages?

http://www.brightsparkmagnetos.com/easycap/universal/easycap_for_joe_hunt.htm
 
Jim I found out a long time ago if the point need cleaning not to use a points file or anything abrasive to clean them, as doing so takes the hardening off the points and will make them wear out quicker, I just use Metho to clean my point when needed, I learned this a long time ago running a JH on my 81 Triumph Thunderbird, the JH on my Norton I haven't touched the points yet in 13 years on the Norton.
Another thing isn't a condenser suppose to stop the point from arcing or have I got that wrong, I not so long ago purchased 2 tune up kits from Joe Hunt which includes point, condenser and new plug leads, so far with over 30k miles on my JH the point still looks good and the bike is starting first kick and running great so I leave it alone but I do pull the front cover off on every service to inspect the point and put a few drops of STP on the cam lube pad.
But I have the 2 new tune up kits in my spare cupboard with 2 spare front covers, always thinking a head.
My old Joe Hunt maggie on my 81 Triumph clocked up a lot of miles on that bike and was very rare I touched that JH, I brought the JH off a mate who was running it on his race Triumph, he had it completely rebuilt before selling it to me for the cost of the rebuild, 9 years an 250k km was done on that bike before I sold it.

Ashley
 
Memories of Norluck.... seeing that point cam
Don't bring that up, he kept sending me PMs and I tried to help him but he just wouldn't listen as I knew what he was doing wrong, some people are just beyond help and he upset a lot of people trying to help him, it got so bad I stop replying to his messages, we are all here to help but he became a nuisance.
 
New points will corrode and pit from the arching spark. The points heat up and the surface deteriorates. For a short time period the JH magnets were too strong and the plastic points arm would actually heat up and melt/deform until the points closed and wouldn't spark - so they went back to previous rare earth magnets. When the points corrosion gets bad - then there is missing above 5000RPM (it may start and run fine at lower RPM). You don't see any points arching below 4000RPM. I only have to file the points with diamond abrasive once a year so its no big deal. Runs clean to 7500RPM+ till then.

regular condenser is # S6-136

I'd like to know if anyone's had better luck with the capacitors below.

You can Switch condensor for capacitor - 150 nF or 220 nF capacitor

http://www.brightsparkmagnetos.com/easycap/index.htm

http://www.brightsparkmagnetos.com/easycap/universal/easycap_for_joe_hunt.htm
 
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Jim

I have never used those bright spark condensers but back when I was racing I used the physically larger condensers marked R that Morris used to sell. Lots of guys down here used JH Morris rotating magnet type magnetos and we found the smaller standard condenser would last maybe one season max in racing conditions. I never had one of the larger ones fail. They cost about twice as much but unfortunately I don't see them on the Morris site any more. Hunt list a few different condensers but not sure if they are a viable alternative.

I'm actually putting my old 500 back together after more than 10 years parked up. I recently bought one of your long rod piston sets for it.

I will be going over the mag and getting some spares together and will try to track down a couple of those larger condensers. I'll maybe ask Peter Lodge what he is using in his magnetos. The ES2 that got 3rd this year at the Manx.
 
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Jim I understand about the heating of the points and all and I ride my Norton hard through the gears and well over 4000 RPMs, yes I do ride under that when riding around the suburbs but not out in the rangers or out on open roads, but I also run mine out in the breeze and not behind a hot motor, so whether that make a difference as you have said before it don't, but I recon it does play a big part.
I have run 2 JHs both out the side in the breeze, one old 2 rare earth and the new 4 rare earth on the Norton, with the cam and head work I am running it don't get up and go until it gets over 4000 RPM, I have replaced the condenser after it got damaged to a lay down years ago (front cover and condenser damage) and going back to my old Amals I been doing a lot of open full throttle runs without any miss fires, in fact its the best my Norton has been running in years since going back to the Amals and tuning them in, I have never ran the Norton with the JH and Amal till now as you know I had your PWK carbs and the JH and to be honest its running better with the JH and Amals tuned to my hot motor.
As I have said in 13 years and 30K mile on the JH I haven't touched the points yet, I inspect them when doing oil changes but the points are good, I just changed new spark plugs when I installed the Amals and with 30K mile on the old plugs they are still looking the same as the first day I put them in with no wear on the electrode.
My mate Paul has been running an old JH on his Triumph 650 police special motor hardtail and after 17 years he just threw in a new set of points, condenser and leads for the first time in all them years, it also hangs out in the breeze, but it started to run a bit rough and harder to start, so was time to put a tune up kit in the JH, its now running like it should again.

Ashley
 
New points and condenser once a year does the job. Cleaning the points is easier and lasts nearly as long. I did have a condenser fail on this mag once and leave me stranded. I cut it open and was suprized how simple it was. See link below for an example. So condensers get replaced. I'd like to try the larger "R" marked condensors if I can find them.




Below is a magnified image of the flexible diamond abrasive sheet (available from McMasterCarr) This stuff is amazing and it only takes a few seconds to clean points to a smooth surface. Tiny diamonds are imbedded in tiny nickel islands fastened to flexible fiberglass sheet. Not cheap.

magneto inspection with modified cover
 
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Jim have you investigated what Hunt call their high output condenser? Could this be an equivalent to the Morris R scribed condenser perhaps?
 

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I'll check it out. Also the R condenser and the easy cap to find out which makes less arching at the points.
 
Hi Jim I had one of those brightspark easy cap fitted to my Lucas K2FR mag it ran well with no problems,
I’m quite interested in one of these JH magnetos how accurate are they ie to degree to each cylinder as the Lucas is always 2 degrees out at best and reliability for a seasons race?
 
Hi Jim I had one of those brightspark easy cap fitted to my Lucas K2FR mag it ran well with no problems,
I’m quite interested in one of these JH magnetos how accurate are they ie to degree to each cylinder as the Lucas is always 2 degrees out at best and reliability for a seasons race?
I'm going to try one of those capasitors and see if there's any difference and if its easier on the points. The timing seems good with the JH as far as I can tell. The spark is a lot hotter with the JH because of the neodemium magnets. Starting is easier. Very reliable. Clean or replace points periodically same as you would on an old 1960s car (I do it yearly). If the points get old or dirty it can miss, the quick fix is to clean them with abrasive. The only failure I've ever had was a condenser. I use a bullet connector on the condenser wire which makes it easy to change. Once I tried a JH I got rid of all my Lucas magnetos & parts.
 
I'm going to try one of those capasitors and see if there's any difference and if its easier on the points. The timing seems good with the JH as far as I can tell. The spark is a lot hotter with the JH because of the neodemium magnets. Starting is easier. Very reliable. Clean or replace points periodically same as you would on an old 1960s car (I do it yearly). If the points get old or dirty it can miss, the quick fix is to clean them with abrasive. The only failure I've ever had was a condenser. I use a bullet connector on the condenser wire which makes it easy to change. Once I tried a JH I got rid of all my Lucas magnetos & parts.
Do you feel you do not need an auto advance? Lack of an auto advance keeps me on the fence. Thanks.
 
Jamesp, my 850 starts on first kick every time without an auto advance even if it sat for a while, when I first set it up I only static timed it and if I got any kick back I just slightly retard it till no kick back and when I say slightly I just mean that, setting the point that are just starting to open at 28 degree is so close as well the spark plugs gap is set at 18thu not 25thu as normal.
I ran an older JH on my 81 Triumph Thunderbird for 9 years without an auto advance and it was a first kick every time and 250k km with it, the newer JH has been on my Norton now for 13+ years and it always starts on first kick and I haven't touched it with 35k+ miles on it.
Everyone makes a big deal about retarding the JH to start, well I have had no problems at all starting my high compression motor and most of the time it's fired up and running as it get through 1/2 a swing on the kicker (I run the longer RGM T160 kicker) they are so good and one hell of a spark.
Would I ever go back to any other ignition, no way the JHs work so well and are so reliable and are so easy to maintain, well on my hot 850 anyway.

Ashley
 
Jamesp, my 850 starts on first kick every time without an auto advance even if it sat for a while, when I first set it up I only static timed it and if I got any kick back I just slightly retard it till no kick back and when I say slightly I just mean that, setting the point that are just starting to open at 28 degree is so close as well the spark plugs gap is set at 18thu not 25thu as normal.
I ran an older JH on my 81 Triumph Thunderbird for 9 years without an auto advance and it was a first kick every time and 250k km with it, the newer JH has been on my Norton now for 13+ years and it always starts on first kick and I haven't touched it with 35k+ miles on it.
Everyone makes a big deal about retarding the JH to start, well I have had no problems at all starting my high compression motor and most of the time it's fired up and running as it get through 1/2 a swing on the kicker (I run the longer RGM T160 kicker) they are so good and one hell of a spark.
Would I ever go back to any other ignition, no way the JHs work so well and are so reliable and are so easy to maintain, well on my hot 850 anyway.

Ashley
Thanks for your input, Ashley. I know there are benefits to having a JH, and I am not concerned with starting. What you say sounds good. What I would like to know is what happens when the motor gets going above 2000 rpm and the motor wants spark advance to build more power. Does it really matter on a Norton motor if it does, or does not, get that extra shot of power that an advance curve would provide?
 
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Thanks for your input, Ashley. I know there are benefits to having a JH, and I am not concerned with starting. What you say sounds good. What I would like to know is what happens when the motor gets going above 2000 rpm and the motor wants spark advance to build more power. Does it really matter on a Norton motor if it does, or does not, get that extra shot of power that an advance curve would provide?
Same James for racing purposes
 
I ran a JH on a track bike this year. Starting was super easy, instant. I had the retard lever option fitted but never used it. Mags spark better as the revs rise, that’s why they were so ubiquitous in racing for decades !

Sent you a PM Brian.
 
Thanks for your input, Ashley. I know there are benefits to having a JH, and I am not concerned with starting. What you say sounds good. What I would like to know is what happens when the motor gets going above 2000 rpm and the motor wants spark advance to build more power. Does it really matter on a Norton motor if it does, or does not, get that extra shot of power that an advance curve would provide?
James the JH has no troubles at all as soon as you hit the throttle the better they go, the faster they spin the bigger the spark, I can go from putting around to giving it a handful and it never hesitate to wind up, in fact it just goesssss from slow revs to full rev, if it didn't do that I would have not invested the money in one but this is my second bike running a JH and just know how they perform.
To be honest I just get over all the B S that people carry on about not having an auto advance, the JHs just don't need them and most that complain about that have never used one and have no idea how good they are, they produce a huge spark and have seen the spark jump a fair way when one of my plug leads came out of the maggie front cover and the spark was jumping a few inches away from the cover to the lead and the motor didn't miss a beat except for a slight mis fire, you can actually hear the spark crack.
Another good thing running a JH is the plugs run very clean and last a very long time I just change my N7YC a few months ago for the first time in 13 years since putting the JH on, I was installing my old Amals after running PWK carbs for 13 years, the old plugs still look great after 35k miles on them, I take a pic of them tomorrow just to show how good they still look, I just decided to change them for new ones to set up and tune the old Amals back in.
The best thing I don't need a big heavy battery and don't rely on a battery for starting or running and I have cut back to very min wiring, just wiring for the HL, BL & TL and horn and a simple toggle switch (hidden of course) for stopping the motor.
What else can I say, I love my Joe Hunt and the Norton has been running the best it has ever run since new.

Ashley
 
Thanks for your input, Ashley. I know there are benefits to having a JH, and I am not concerned with starting. What you say sounds good. What I would like to know is what happens when the motor gets going above 2000 rpm and the motor wants spark advance to build more power. Does it really matter on a Norton motor if it does, or does not, get that extra shot of power that an advance curve would provide?
No - additional advance does NOT add power at higher RPM. First you set your timing at full advance at high RPM. 28 deg far a small chamber high compression motor. 31deg max for low compression. 28 deg (sometimes less) is best for a high comp Norton racing motor as proven on dynos by many tuners. More advance than that at high RPM will cause pinging and damage. All the advance does is give you retarded timing at lower RPM so you can start it without kickback.

You want full advance by 2000 or 3000max RPM for best power at lower RPMs - same as original stock points ignition with mechanical advance. All the EIs with long advance curves have reduced power at low RPM because the timing is too retarded at lower RPMs. In this respect most currently available Norton EIs suck.

You can spend $1000+ for an EI with an ideal full advance at 2000RPM (matching original mechanical advance). Someone is currently putting together an affordable EI ignition that will achieve this ideal advance curve to match the original points advance curve. Its been street tested and it does indeed provide more power at lower RPM - same power at high RPM.

I achieved this in the mid 1980s with a Boyer that was modied with resistors to shorten the advance curve. The description is in my race manual. I did it to get more drive coming out of the turns.

Note that fixed advance is prefered for racing (as long as you can start it).
 
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Thank you to everyone who responded to my question regarding JH magnetos and spark advance. I think I understand what you are saying about the spark advance. I can see that their is real passion out there for them. It also looks like you can get by without an electric starter if you have a decent leg.
 
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