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Posted By: Samsmc1 Pre unit magnetos / generators - 12/24/19 8:34 pm
Are any of you dialed in on what Triumph used for magnetos?
The Lucas book list 4 different mags that could come on a '57 pre unit 650 depending on whether it's a T110 or TR6.
Even the 500cc Tigers and Trophy's had several different numbers.
Does anyone have an unmolested '57 T110 they can look at and tell me what it has?
Also what's the difference between a K2F and the competition K2FC? I always thought the comp mags were waterproof, but the drain hole in the bottom of all the K2FC mags I have kill that.
I have a question on generators - most have a manufacturers date stamped into the case with all the pertinent data. Would a '57 T110 have the date code '57 in it or would '56 and maybe even '55 still be appropriate?
Posted By: HawaiianTiger Re: Pre unit magnetos / generators - 12/24/19 9:37 pm
As far as the mag is concerned, it would have come standard with a K2F mag, but available with the auto advance, or the K2FC in either configuration. I would select which I would like most. I would prefer the K2FC with auto advance as the most desirable set up. The Mag's ID plate also lists year of manufacture which would like be the model year or year previous.
The K2FC comes with a water proof end cap, all aluminum, and Glyptal coated screw in pick-ups with rubber boots over the ends. The ID plate is red instead of black.
The dating info applies to the generator as well.
So the majority of T110's that year would have the K2F mag with the option of the distributor to order the bikes with the other options, which increased the price of course.
If you're concerned about originality, don't fret over the spec of the mag. It would be correct with any combination.
One of my '55 T110's came with a K2FC mag with auto advance. My '59 Bonnie came with that and a manual advance. I just hated the fuss of messing with another lever on the handlebar, myself, although it came in handy when I got a tank of crap gas.

Posted By: Samsmc1 Re: Pre unit magnetos / generators - 12/26/19 5:59 pm
What about the generators - they all seem to have a date stamped into the housing.
If I was to show this bike knowing that it was going to get picked at really hard, how far in advance can the date on the generator be in relation to the year model?
Also do you have any idea where I can document all of this info? The Bacon restoration guide is nearly useless in most cases.
Posted By: HawaiianTiger Re: Pre unit magnetos / generators - 12/26/19 6:47 pm
Second guessing show judging is a fruitless enterprise. Documentation is key. When I went to a show, I kept a folder with all the pertinent specs in it, along with period magazine tests and advertising.
I know of no documentation about Lucas dating. However, Lucas did publish a glossy color catalog of all it's motorcycle equipment each year and that could be of some help. It's a matter of common sense, mostly. They were a proprietary supplier, so Triumph wold order in advance a specific amount of product. Likely the year prior, but no reason that it couldn't be the same model years as the bikes were made all the way into summer for that year. Two years? It's possible, but generally speaking a company tries to keep only enough inventory as is needed to lower costs, so two years would be contrary to that practice, but not impossible.
When looking for documentation, I left no stone unturned. That was mostly pre internet days, too. I had a collection of magazines from that period both US and English, mostly all gone now.
I had every parts books ever made, even if just a copy. What helped me a lot was knowing several older gentlemen who actually owned, rode, or sold these bikes when new. Most of them were racers and are now no longer with us. Also, I knew the archivist at the San Diego Antique Motorcycle club well, and Capt. Al Mark who collected massive amounts of material, especially videos.
All this allowed me a keen competitive edge in shows.
Posted By: Irish Swede Re: Pre unit magnetos / generators - 12/26/19 8:34 pm
I believe Bill has stated it exactly right.

I have judged British bikes in the Antique Motorcycle Club of America. Bringing as much documentation as you can with your bike makes judging easier and quicker, with less mistakes and arguments.

I can't add anything to what Bill has written here.
Posted By: HawaiianTiger Re: Pre unit magnetos / generators - 12/26/19 9:21 pm
I would add that parts books originally used by dealers can offer a lot of extra information as witnessed by a recent thread where the piston's part numbers were incorrectly entered in by the factory. Written corrections by dealers can really help sort out discrepancies, especially when viewed in the context of history where the witnesses are no longer around.
Also, I had nearly all of Jomo's Service Notes, and Triumph's Dealer Bulletins. These are worth finding if you're going to be restoring these bikes.
Posted By: Samsmc1 Re: Pre unit magnetos / generators - 12/26/19 9:32 pm
We're all on the same page about documentation.
Problem is we're dealing with British motorcycles - the only thing that can possibly be worse would be Italian bikes.
Let me give you an example - the '57 thru '65 Triumph 650 parts books show a push rod tube that has a bulge in the bottom and a smaller one at the top.
Every bike I've seen has a straight tube and everyone I've asked with a bike in this range say the tubes on their bikes are straight.
I have some tubes that look like what's in the book, but they're way too long for this head / rocker box assy.
What do I say to a judge who has had his face in a Triumph parts book?

I just finished (nearly) a '55 BSA A10 Golden Flash.
For the '56 and later, there is all kinds of documentation on what's correct and what isn't, whereas the '55 is vastly different up close.
Contact the folks at the main BSA club for details, they don't know and could care less.
This thing ate me up until I found enough pictures to back up what was correct.
I always thought Triumph was better before this old dog started eating on me.
By the way, do the numbers on the transmission mean anything? If yes, where can I get educated on transmissions.
Thanks for your help.
Posted By: bodine031 Re: Pre unit magnetos / generators - 12/26/19 9:42 pm
Doug Wood may be able to shed some info/lite. R&D engineering 610-369-7855 [email protected]
Posted By: HawaiianTiger Re: Pre unit magnetos / generators - 12/27/19 4:04 am
When old Harry Woolridge was doing serial number vs. factory dispatch searches for us, he often quoted the gearbox number along with the engine number. So, somewhere, likely in the Motorcycle museum in England, there are records that list these things. I've had good luck emailing the museum and getting responses about numbers at least. Sometimes Woolridge would have more info like who the bike was shipped to (Jomo or Tricor) sometimes, for example, my old 6T, he listed the dealer it was shipped to originally down in Oz. Sometimes he would list some specs, like color, too.
Posted By: Samsmc1 Re: Pre unit magnetos / generators - 12/27/19 4:32 pm
This T110 was a fairly complete bike when I got it, but in very bad shape.
It does have what I assume to be the original trans on it, so I can give the numbers to anyone who may have info on what the numbers should be.
Although I have built many Triumph engines back in the '70's, I never realized how fragile the heads were from a rigidity standpoint.
This one was way out and when I started to place it in the mill, I saw that clamping it down would twist it flat. I figured it would twist back after milling, so what do I do?
A retired machinist friend on mine (BSALLOYD on other forum posts) told me about having a surface lapped (not ground). He took it somewhere and had both surfaces lapped.
I have since heard that this method is used quite often in rebuilding hydraulic pumps.
You might keep this in mind if you ever run into a similar situation.
Posted By: HawaiianTiger Re: Pre unit magnetos / generators - 12/27/19 6:43 pm
Well, I haven't milled a head in decades. They don't need attention unless they are way out, like more than 10 thou. Like you said, when you torque them down, they flatten right out. Besides, you can straighten them if you want by slightly over-correcting the bow, then heat in an oven. More details available about this if you search the site. As for cracks, which nearly all of them have, don't bother with them unless they are getting close to the valve seat. Then you're kind of screwed....probably should source another one.
Also, I can't remember the email address for the London Motorcycle Museum's archivist, but visit their site, send a message and see what happens. LMM
Posted By: Boomer Re: Pre unit magnetos / generators - 12/27/19 8:38 pm
All the preunit Triumph dispatch records I have seen list in order: frame #, model, engine #, gearbox #, frame type (rigid or sprung), gear ratio, order #, date dispatched, and then most of the time a hand written note of distributor and country. So you can write to several vintage clubs and get this info for usually a fee as they will have copies of the dispatch records.

Bill B...

PS: I should add that the preunit gearbox number was close to the engine number but not the same. Later in the run, like Duplex bikes, the numbers get farther apart.
Posted By: Samsmc1 Re: Pre unit magnetos / generators - 01/19/20 10:54 pm
I need help again with this magneto for the '57 T110 I'm working on.
The book calls for a 42344 part number and shows the advance to be manual.
I just found the mag that I think came from this bike. It has a threaded plug in the hole that houses the advance cable.
I have another mag with the same number 42344 that has the same threaded plug plus the auto advance still with it.
The Lucas book and the Triumph parts list definitely show a manual / cable advance.
Those two sources appear to kill the idea of a auto advance being available on the T110.
Will the shipping documents several of you mentioned detail what mag this engine came with?
Also the mag casting on several of these housings have a circular casting that has a 39 on one side and 49 on the other side.
I have a mag here tagged as 42368 (late '50's Norton) with the same casting on it.
Anyone have any idea what the casting means?
Posted By: HawaiianTiger Re: Pre unit magnetos / generators - 01/20/20 12:36 am
No idea about stamping numbers. The parts book list all the options I detailed above as accessory part numbers which means they were available to the dealers and also to owners. Whether the factory supplied the dealers with one configuration or not is down to who ordered the bike. Sometimes you can find records that list these things but they are rare. Usually if the motorcycle museum has any records at all they will be engine number, frame number and sometimes gearbox numbers and occasionally more info. I think if you're going to find info detailing things like magneto configuration, it will like be from the distributor or dealer. Jomo and Tricor often issued bulletins specifying things like this.
So, you can break it down to two categories. The first is the factory supplied configuration and second the dealer configuration. In between there is the possibility of mods being done by the distributor.
The distributor supplied bikes often differed from each other, and sometimes significantly. You hear east coast vs. west coast. This was particularly noticeable with the race bikes, like the TT's.
Sometimes photos of new bikes at the dealers are a wealth of info.
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