Elliott Montagu’s 1927 Triumph N model restoration – Part 6

The next thing to do was to set the timing.

The “Instruction Book” says to set the points breaking with the piston 7mm before TDC and ignition lever fully advanced.

VMCCUK old Triumph expert, Peter Cornelius, (cornelp@xtra.co.nz or peter@triumph.gen.nz ) recommended setting the timing at full retard on top dead centre. He maintains that the fuels we use now are so different to those used in the twenty’s that the tuning figures are no longer relevant. With the points breaking, the piston at TDC and the lever in the fully retarded position it is only necessary to advance the lever until the engine sounds and pulls OK. Not very scientific but apparently it works.

The timing was set and with a couple of mates watching I kicked it over. It didn’t start because we had set the timing with the lever in the fully advanced position! The timing was reset and amazingly the engine fired and ran on the first kick. This was quite a moment for me. Perhaps in the fifties, after being thrashed around a paddock for years the bike was discarded. The engine hadn’t made a sound for maybe sixty years and there it was running again with that old fashion characteristic exhaust note.

The valve timing was obviously out as the engine was blowing back through the carby. The valve timing was altered by one tooth and that fixed it. (These engines don’t have valve overlap).

There were a few small problems to fix. The petrol cock fitted is a tapered rotary type and it was leaking about half a cup of fuel overnight. Lapping with polish got this down to about half a teaspoon overnight. The difficulty in seating the needle valve in the float chamber is apparently common to these carbys but it appears that once the engine is running it’s not a problem. I have tried lapping the needle in, making a new needle and attaching a short rubber tipped needle from a modern carby to the needle. This didn’t work because when the diameter of the short rubber tipped needle is reduced to fit, the flutes disappear and the fuel flow past the tip is reduced.

The oil system on this engine is interesting. It is a total loss system. Oil is carried in a tank integral with the fuel tank and is delivered by a hand pump on the tank or alternatively by a dripper type system that is driven off the end of the crankshaft by a helical gear. This system was intended to be the primary system and even though a sight glass was incorporated the hand pump was retained because of customer distrust for the automatic system. We had several goes at making a helical gear which drives the automatic dripper but it was not successful. The shaft on which the gear is fitted runs at right angles to the crank shaft and is mounted directly in the crankcase. There is no bushing and it’s difficult to fit bushes so as the casing wears the gear doesn’t mesh properly. I decided to stay with the hand pump. Prior to starting the engine for the first time the pump is operated four times and oil runs down the pipe from the pump, through a non return valve and directly into the crankcase. The spring loaded non return valve in the pipe prevents a continuous feed into the crankcase. The revolving flywheels throw the oil up into the cylinder to lubricate the piston and the cams and associated gears located in an adjacent chamber are lubricated by oil mist. The external valve stems are not lubricated but do run in guides. I’m told that as money saving measure valves in earlier Triumph engines didn’t have guides. The stem ran in the barrel/head casting. Riders now give the valve stems a squirt of chain lube at refreshment stops. I couldn’t get the piston in the oil pump to seal using two leather buckets as was the original set up so I made a brass piston with two rubber rings and fitted it to the plunger. This was tested by pumping into a container and the volume of oil delivered was consistent with the volume of the pump cylinder. When riding the bike the idea is to operate the hand pump every ten miles and if you’re worried that there isn’t enough oil in the engine the operator’s manual suggests an extra pump and observe the exhaust. A slight blue trail of smoke behind the bike indicates you’re OK. I bought one of those $15.00 matchbox size speedo odometer things so I would know when its ten miles since the last pump. I was told that initially one gets over concerned about the amount of oil in the engine and the rider pumps too often. Even after being told I did this on my test rides at home and oil ran out of every orifice onto my rather lengthy drive. She was not pleased.

I was able to ride on my drive but as the bike is fairly highly geared I couldn’t get past second gear. The hand change is challenging but I’m sure I’ll get used to it.

I contacted a 1st Time Examiner and made an appointment for an examination. The machine was loaded into my van and we went to the Club rooms on a fine Wednesday morning where Norm Chester carried out the inspection. The bike was passed and the paper work was submitted to the DOT who wouldn’t license it until I produced a receipt and a statutory declaration saying where and from whom I purchased the bike. This is not necessary if you can produce the transfer papers that go with the purchase of a licensed bike. They also wanted a statement from Canberra to the effect that according to their records the bike wasn’t imported after a certain date. Surprisingly DOT in Canberra was able to respond in about nine days. The statement was duly provided and a plate was obtained after the usual hour wait at the licensing centre at Midland. With a plate I was now able to try it on the road.

The road that goes past my place is downhill in both directions which means an uphill climb to get home both ways which is not good for a new engine. There is one shortish flat road off the main one so I decided to use that. I put a temporary basket on the carrier and loaded up some tools and went for a ride. The bike rides quite well. The front forks absorbed the bumps in the road and the generously sprung seat took care of the rear. The front brake, when applied, doesn’t produce any detectable change in the speed of the machine but the rear brake works well. One has to judge these things by the standards of the day the bike was built. The gear lever isn’t all that positive as the gear box is connected to the handle with a turnbuckle. The original connecting rod had a spring arrangement in the rod which apparently makes the gear selection more positive. I’ll have to borrow one as a pattern and make one. Hopefully that will fix the problem.

I think I’m going to like this old bike and now I must get a few k’s on it before the roaring Twenties Ride on the 4th of May. There are a few other jobs to complete. I managed to scratch the tank when the valve lifter control made contact on full lock. The lighting set (which took a couple of years to collect) has been panel beaten and nickel plated along with some more bolts and washers. These items and a more suitable basket have to fitted. It’s been a long time since I started this project and at times it’s been challenging but always interesting. I’ve learnt a lot and had a lot of help and advice from members of our Club. This is part of what this Club is about.

The first object of the Club is “to encourage the ownership, use and preservation of motorcycles and other similar vehicles more than 25 years old” That doesn’t only mean old English bikes it means what it says and that is bikes over 25 years old. You don’t have to be an expert (this is only the second bike I have restored). The way I see it is that you should start with a bike that is not too exotic, one for which parts are readily available eg Matchless, Triumph, AJS or BSA etc. You need some mechanical knowledge, a reasonable tool kit and at times, access to a lathe or someone who can turn bits up for you. Parts sometimes need to be bronze welded, silver soldered or electric welded. There are people around who can do this for you. Why don’t you consider giving it a go?

Riding notes from the Running Instructions issued to the new owner of a Triumph model N.

“To start away with the engine running hold up the clutch lever, which is placed on the left hand side of the handle bar, place the gear lever in low gear position (right back). Very gradually release the clutch lever, at the same time opening the throttle slightly as the engine takes up the load, when the machine will glide smoothly away. If the machine starts with a sudden jerk, the clutch lever has been released too quickly. If the machine jerks forward slightly and the engine stops the throttle has not been opened sufficiently to enable the engine to take up the load. When the machine has attained reasonable momentum, raise the clutch lever and at the same time move the gear lever forward into the second gear position, gently releasing the clutch lever as soon as the gear lever is in the second gear position. Top gear which is right forward is engaged in a similar manner as soon as sufficient road speed has been attained. If after changing up from low to second or second to top the machine goes forward jerkily it is a sure sign that the change of gear has been made to early i.e. before sufficient road speed has been attained. The present day motor cycle is controlled more easily than a car so riders should understand that it is a simple matter to get away quietly and smoothly. The road speed should be controlled by the throttle control with the air lever fully opened. Never allow the engine speed to become so low that the motion of the machine becomes jerky as this put severe strain on the transmission and is bad for the engine. When approaching a hill the best climb will be made if the throttle opening is increased sufficiently early to allow the machine to start the climb at a good speed. Similarly if the hill will not be surmountable in top gear the change down to second gear should be made before the speed is too low for top gear. To stop the machine at the conclusion of a run declutch and close the throttle using the foot brake to make the machine come to rest at the desired stopping place.”

Some notes on starting a cold engine are also of interest.

“When the engine is stiff to turn owing to the oil being cold the engine may be freed as follows: Close air lever, open throttle lever about half way, raise exhaust lever and slowly depress kick start until the inlet valve commences to open. Now release exhaust lever and continue the stoke of kick starter until resistance due to compression is felt. The engine will now have sucked in some very rich mixture which will thin the oil slightly making the engine easier to rotate by means of the kick-starter. Repeat the above once or twice, return levers to the position normal for starting. Press the tickler until petrol pressure is just felt. Fully advance the ignition lever, open the air valve half way, open the throttle slightly, raise the exhaust lever, smartly depress kick-starter at the same time releasing the exhaust lever just before the kick-starter reaches the end on its stroke to allow the exhaust valve to close just before the moment of firing. After starting regulate the speed of the engine with the throttle”.