Hoping someone work this one out: Bike kicks back like a mule and hard to start when cold but seems to run well once going. I suspect it might be a little advanced. Sadly when i come to start it to strobe I cant get the damn thing to even start. Grrr. So I set the RH cylinder on TDC compression by finding the crank dimple and observing the piston rise after the inlet valve has closed. I have worked out that 82mm piston stroke = 164 mm (up and down) or 360 degrees. The manual says static timing is done a 14deg BTDC so i've set a gauge at 14/360 X 164 = 6.377mm BTDC. This looks good as the line on the points rotor is about to open the points. But.....it's the wrong points? Manual says RHS cylinder is run of the LHS points with a BY connection. This is about to open the RHS points with the BW connection? For this to happen the points shaft must be 180 degrees out. Can a Triumph engine be re-built like that?
Triumph T140E US Import To UK Static Timing
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T140E with points must be a 78.
Also for static timing, you should also be able to remove the large screw-in plug towards the front of the primary chaincase and, at ~38 degrees BTDC, observe the moving mark (stamped line) on the alternator rotor line up with the fixed pointer pressed into the chaincase?
Which manual? In the Triumph workshop manual, I read to set static timing @ 38 degrees BTDC, having locked the auto advance in the fully advanced (38 degrees BTDC) position.
On a 73-78 T140, the "crank dimple" is at 38 degrees BTDC according to the Triumph workshop manual, Sections B27 and B28?
Also for static timing, you should also be able to remove the large screw-in plug towards the front of the primary chaincase and, at ~38 degrees BTDC, observe the moving mark (stamped line) on the alternator rotor line up with the fixed pointer pressed into the chaincase?
Which manual? In the Triumph workshop manual, I read to set static timing @ 38 degrees BTDC, having locked the auto advance in the fully advanced (38 degrees BTDC) position.
speedrattle
Well-Known Member
i would suggest that you would likely benefit from removing the points and installing an electronic ignition. they are simpler to set and require no maintenance.
an ignition using points and condenser is an interesting historical artifact these days, and is essential on a motorcycle intended for show.
but if you want to ride it, EI will save you vast amounts of fussing.
an ignition using points and condenser is an interesting historical artifact these days, and is essential on a motorcycle intended for show.
but if you want to ride it, EI will save you vast amounts of fussing.
The I suggest you also read the Triumph 1978 T140E Owner's Handbook, pages 28 and 29.
Page 28:-
... then note the first paragraph on page 29 ...
As I asked in my previous post, which manual/book? Neither the Owner's Handbook nor the Triumph workshop manual describe the procedure you are using. Workshop manual Sections B27 and B28 are titled "IGNITION TIMING -INITIAL PROCEDURE" and "STATIC TIMING WHERE NO STROBOSCOPE IS AVAILABLE" respectively.
+1.
Haynes manual states at picture 7.4 page 89 (and in text): "Using the crankcase timing plug to find TDC". You then need to turn the engine by the requisite amount to get about 14deg BTDC (varies) for static timing. Alternatively the rotor has a marking at full advance (38deg BTDC) which aligns with a crankcase pointer. This is why when strobing you have to rev the bike up to 3500 - 5000 (varies) to fully advance the engine and get the marks to align. For the thread contributors: The double points system can be tricky to set up and if the AR weights are iffy, say the spring is not pulling the weights properly or has snapped its easy to set the timing incorrectly. So as I don't see why the points cam points to the wrong points (the original question) and the backplate is at the end of adjustment and I have to pull the backplate off to look at the AR weights I thought: "why not do what everyone else does and junk the whole pesky lot for electronic ignition?". It's currently on order. A Boyer kit 52 which will work with my new 12V coils on low compression bikes (especially a T140) - Mr Bransden advises this is so.
Absolutely I have trod the path you advise.
You have a problem with your motorcycle. Your motorcycle was made by Triumph. The same Triumph company and factory produced both a workshop manual covering your bike and an Owner's Handbook specifically for your bike. Amongst the information contained in them is how to set the timing with points.
Otoh, Haynes did not make your motorcycle. Haynes manuals have a generally poor reputation - in other internet forums, including ones for old Triumph motorcycles, you will find them described as "excellent ... as door stops, under the short leg of a wobbly bench, table, etc." and similar derogatory but true (first hand experience) comments.
You are the one with the problem motorcycle. The advice in the Haynes manual either does not work or you have made a fundamental mistake. The links I have posted are to the Triumph workshop manual and Owner's Handbook online that you can read for free in their entirety.
You have asked for advice and been given it. Note none of the other 40-odd readers of your thread have contradicted my advice. So why are you wasting both your time and mine arguing about it, instead of trying it?
To my certain knowledge, Ernie ("Mr Bransden") has "advised" this since he started selling his electronic ignitions; i.e. for about the last fifty years. When he started out, his main competitor for electronic ignitions was the Lucas Rita; his claim made his e.i. look cheaper than the Lucas, because they always supplied two 6V coils with a Rita for a twin.First-hand experience:-
. Ernie has never put a figure on "low compression"; your bike should have 7.9:1 pistons, this c.r. might be low enough for 12V coils in series to work.
. In the 50 odd years Ernie has been printing the same advice, the chemical make up of 'petrol' has changed dramatically, not just by the addition of ethanol.
. If you experience problems and ask for help from Bransden Electronics, one of the first questions you will be asked is if the bike has 6V or 12V coils; if you advise 12V, you will be advised to fit 6V.
If you have not done so already, I advise checking their primary resistance (between the threaded terminals) with an Ohmmeter or a multimeter set to Ohms. A coil's 'Volts' rating is only shorthand for its primary resistance; when Ernie started giving his advice that 12V coils would work with multiple cylinders with low c.r., "12V" coils had a primary resistance between 3 and 4 Ohms. This is important because:-
. the higher the primary Ohms, the lower the primary Amps drawn;
. the lower the primary Amps drawn, the lower the secondary (HT) power ... until the coil cannot produce a spark when required;
. some coils currently available, including some made by the current "Lucas" brand user, have been found to have high primary resistance; when connected in series to an e.i., they cannot produce a consistent HT spark.
Finally here, still from first hand experience; assuming your bike still has its original 'positive earth' electrics, I advise against connecting either the "Transistor Box" Red wire or the coils array positive terminal to "POSITIVE FRAME EARTH" as shown in the fitting instructions wiring diagrams:-
. the "Transistor Box" Red wire is the supply to the electronics, connect it directly to the battery +ve terminal;
. connect the coils array positive terminal either to the bike's existing Red wires network (which is connected to battery +ve) or also directly to the battery +ve terminal.
Also:-
. Ensure there is an obvious Red wire connection to an engine component, test for good electrical continuity between the engine connection and battery +ve.
. Consider fitting a 5A or 7.5A fuse to the "Transistor Box" White wire, perhaps where it connects to the bike's White/Yellow wire from the handlebar kill switch (or a bike's White wire if the kill switch is not in use)? Reason is if there is a short circuit in the ignition circuit components, the bike's standard fuse is rated too high to protect the e.i.
First-hand experience:-
. Ernie has never put a figure on "low compression"; your bike should have 7.9:1 pistons, this c.r. might be low enough for 12V coils in series to work.
. In the 50 odd years Ernie has been printing the same advice, the chemical make up of 'petrol' has changed dramatically, not just by the addition of ethanol.
. If you experience problems and ask for help from Bransden Electronics, one of the first questions you will be asked is if the bike has 6V or 12V coils; if you advise 12V, you will be advised to fit 6V.
If you have not done so already, I advise checking their primary resistance (between the threaded terminals) with an Ohmmeter or a multimeter set to Ohms. A coil's 'Volts' rating is only shorthand for its primary resistance; when Ernie started giving his advice that 12V coils would work with multiple cylinders with low c.r., "12V" coils had a primary resistance between 3 and 4 Ohms. This is important because:-
. the higher the primary Ohms, the lower the primary Amps drawn;
. the lower the primary Amps drawn, the lower the secondary (HT) power ... until the coil cannot produce a spark when required;
. some coils currently available, including some made by the current "Lucas" brand user, have been found to have high primary resistance; when connected in series to an e.i., they cannot produce a consistent HT spark.
Finally here, still from first hand experience; assuming your bike still has its original 'positive earth' electrics, I advise against connecting either the "Transistor Box" Red wire or the coils array positive terminal to "POSITIVE FRAME EARTH" as shown in the fitting instructions wiring diagrams:-
. the "Transistor Box" Red wire is the supply to the electronics, connect it directly to the battery +ve terminal;
. connect the coils array positive terminal either to the bike's existing Red wires network (which is connected to battery +ve) or also directly to the battery +ve terminal.
Also:-
. Ensure there is an obvious Red wire connection to an engine component, test for good electrical continuity between the engine connection and battery +ve.
. Consider fitting a 5A or 7.5A fuse to the "Transistor Box" White wire, perhaps where it connects to the bike's White/Yellow wire from the handlebar kill switch (or a bike's White wire if the kill switch is not in use)? Reason is if there is a short circuit in the ignition circuit components, the bike's standard fuse is rated too high to protect the e.i.
speedrattle
Well-Known Member
it isn't 100 percent. i have boyers, pazons, points/condensor, and ARD magnetos on my junk. whatever works best.
on my 441 victor, i took the boyer off and re-installed a points/condenser system. the boyer would not advance/retard on the single cylinder, so to make it run correctly at higher rpm i had to start it at fixed advance, and it almost tore my leg off one day. apparently the singles do not always do well with boyer ignition. i have no difficulty starting a correctly-tuned 650 twin at fixed advance with an ARD.
ive run boyers for decades, both with single and twin plug applications. and i have an overkill pazon smartfire on a beater A65 that had such a worn-out AAU that i simply could not get it to go and threw up my hands at it.
the advantage of an EI is that it is a set-and-forget ignition, and setting it is childishly easy. the disadvantage of them is that they tend to be sensitive to low voltage. you can kick start a points/condenser system with a flat battery. with an EI, you will walk until you find someone to jump you. good batteries are a must with an EI.
but i confess that the points/condenser system is mechanically interesting, and i use em sometimes just because they are fun to mess with.
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You've hit the point with classic riding. Modern bikes you ride and have serviced. Old classics you can tinker with and get attached to. The question is when does tinkering become a chore coz you're not riding? Points vs Electronic ignition is one of those dilemmas. When the box fails as happened to me with a 5TA on a ferry to France you're finished: recovery time; but on a running bike, points can always be adjusted to at least get you home. Its why I tried to persevere with my points system but I think the dual points is a bit rubbish so electronic is the way to go I think, especially on a non-standard machine.
speedrattle
Well-Known Member
i would take a spare box. ive got one or two around someplace.
i had a new boyer once melt the glue that held the pick up coils together on the stator plate. fixed under warranty.
i had a new boyer once melt the glue that held the pick up coils together on the stator plate. fixed under warranty.
