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Discussion Starter #21
Well I have now fitted the new wiring loom to the bike, & it looks alot better already, just about to go & collect the new boyer, so hopefully should have that fitted fairly soon, I have had a look behind the primary cover & can see the timing pointer on the crankcase but no indication of TDC or 38' do i just rotate the motor so the piston is at the top of the cylinder, then make a mark TDC, then rotate the motor back 38' ??
 

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Whatley's First Law of Brit Bikes: The day you fit a Boyer is the first day you start cleaning up your sloppy wiring harness and faulty charging system, or the last day you ride.
Paul -
Congrats on the new harness. You may never fully realize how much grief that will save you. :D

As you plug your new harness together, you'll want to apply some anti-oxidation grease to ALL the connectors, especially the bullet plugs. You can get this at electrical supply places or even Home Depot. A big bottle is about $4 so it's a great investment. It's the same stuff applied to wire ends when an electrician brings the leads into the main breaker box from the power company. Goes by many names including "No-Ox".

You didn't say where, but I generally place the Boyer box under the tank, between the frame tubes, just over the coils. In this position wiring is very easy, mounting is easy, and there is plenty of cool air. These are all very important considerations.

Low voltage issues plague Boyers. On a Triumph of this age, it is usually found in 3 areas: Battery going bad (not able to deliver 12V), ignition switch going bad (not able to pass 12V), and faulty return wiring (not able to return 12V). I highly suggest you take this opportunity to replace the electrical portion of the ignition switch, especially if you find a date code on it indicating "68" or "69". Most Lucas components are date stamped. The battery and return we've already discussed. There are also a lot of articles on GABMA concerning these several areas which you may wish to read.

When you strobe your timing, simply remove the 3" window on the primary cover. In there should be a pointer in the stationary cover and 2 lines on the rotor. The strobe lamp will find the correct rotor line for you. The mark and pointer should line up at 5000 RPM. If you do not have lines, then I urge you to replace your rotor with a modern Wassel replacement. The older Lucas units tend to give trouble at 30 years, and it can be no fun. (No lines would mean that the original rotor went bad and was replaced with an even older used one. That's no good.)

Hope this helps ;)
 

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Voltage problems can drive owners of electronic ignitions crazy! But there is a simple test that can help most electronic ignition owners test there ignition system. One feature of most electronic ignitions is they turn off when the engine is not turning over. This prevents checking the system using a simple DC voltmeter.

The first thing you must understand is that an electrical circuit must be under load to check for any problems. With the ignition electrical box turned off until he bike is turning over, there is no electricity flowing from the battery, through all of usual problem areas and back to the battery: the fuse holders, switches, connections and grounds. With no load we will not be able to see any problems (voltage drops) as the electrons flow through the system. Because the components inside the ignition box have high and low limits in which they work properly, any voltage drops can prevent the box from turning on and working.

You could put a 4 ohm 50 watt resistor resistor in place of the ignition box and coils (with a Boyer wired positive ground you would connect one end of the resistor to the wire coming from the ignition switch and the other end to the coil terminal where the boxes red and the ground wires are connected.

But if the coils are installed, you can use them to provide the load instead of the resistor. The bikes coils, wired in series, are typically between 3 and 7 ohms and perfect for our test.

All you have to do is lift the wire coming from the ignition switch that is connected to the Boxes white wire and connect it to the coil terminal where the boxes black wire is connected. Remember we have to jump around the box because it is turned off unless the bike is running.

Now you can take your DC voltmeter and with one lead attached to the battery ground terminal go around the circuit and take voltage measurements. Check the voltage as it goes into the fuse and after it comes out. Do the same for he ignition switch, kill button, and connections, the coil terminal where you attached the wire from the ignition switch AND THE GROUND TERMINAL on the last coil in the circuit. Yes the ground terminal!!

At each point you should have the same reading you took at the battery. The reading at the ground terminal on the coil should be zero. If you are showing any DC voltage at the coil's ground terminal you have a bad ground. Trace the ground voltage back toward the battery and the point where the DC voltage goes to zero is the point where your ground really is.

If you have a voltage drop at any fuse holder, switch, connection, or ground it must be corrected or you and your electronic ignition will not be happy.
 

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Discussion Starter #24
Thanks for all the advice I have been given, it is greatly appreciated.

Well finally after installing the new wiring loom, which is a huge improvement already, and fitting the replacement boyer, which again was very straightforward, particularly with the new loom fitted. Also took the opportunity to replace the existing +ve earth wires, which seemed to be everywhere.. all necessary +ve earths are now routed back to a SPG behind the battery. I think there was probably about 5 or 6 connections on the previous wiring loom/ign circuits that had very poor connections !!!

Re-fitted tank and seat, then the moment of truth, would she start & would she run when started. Fired up on second kick, no spluttering or backfiring, what a sweet sound that was too my ears....she even idles fine on tickover..

By the time I was all done it was too late & dark to give her a run so will take her out today & hopefully all will be ok !! Just have to master the gears on the right side now & work out the position of the gears.

Here is to a good ride...
 

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Paul , why arn't you a member of either the Surrey branch or the Mighty South London branch of the TOMMC. l am a member of the latter and we can show you how a well set up old'un can run, including mine. Believe me my T100 was a nightmare before Mr Benn ,a member ,worked all the bugs out and pointed me in the right direction. They have been riding these bikes since the 50's and like a good Shrink , you feel better having chatted to them over a beer or two, plus runs out most weeks to test your bikes up to it1. All for £17.50 a year.
 

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Discussion Starter #27
Paul , why arn't you a member of either the Surrey branch or the Mighty South London branch of the TOMMC. l am a member of the latter and we can show you how a well set up old'un can run, including mine. Believe me my T100 was a nightmare before Mr Benn ,a member ,worked all the bugs out and pointed me in the right direction. They have been riding these bikes since the 50's and like a good Shrink , you feel better having chatted to them over a beer or two, plus runs out most weeks to test your bikes up to it1. All for £17.50 a year.
Did not know anything about it, but will definately join, where do I find info from ?
 

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Discussion Starter #28
Did you check the timing with a strobe? Very important to do. I didn't see a mantion of it in your last post.
Have not done so yet, she seemed to be running fine !

Bit of an issue with smoke though, first of all I was not sure where it was coming from, it appeared to be coming from under the fuel tank, at both ends, only very slight, almost did not see it at first !! but you could smell it, got me quite worried at first, on closer inspection 1 of the rear rocker cap gaskets is broken and is letting oil out onto the cylinder head, which is obviously burning at running temp. So will b e replacing all 4 gaskets, as well as gaskets/washers for the 4 retaining spring bolts (there are none fitted at present).

Hopefully this will solve the smoking/burning issue & put my mind at rest.

Think i will take her in to local bike shop to get the timing strobed as i'm not that confident doing it myself....
 

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....on closer inspection 1 of the rear rocker cap gaskets is broken and is letting oil out onto the cylinder head, which is obviously burning at running temp. So will b e replacing all 4 gaskets, as well as gaskets/washers for the 4 retaining spring bolts (there are none fitted at present).
DON'T BOTHER.

Simply go down to the local hardware store and pick up 4 common, fat, 1" dia o-rings and fit those. O-rings leak far less, and the resilience of the neoprene will keep the caps in place just fine.

;)
 
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