The Nail Files

An oily chain is a happy chain, but an oily tyre is a slippery tyre.

The product reviews and sales material on chain oilers is pretty convincing. Just two drops a minute of oil onto a working chain will greatly extend its life and reduce the need for adjustment.

The market leader uses a gravity-fed drip-feed reservoir, switched on and off by the inlet vacuum of the engine. There is a competitor that uses the motion of the bike to control the feed of oil, but the word on the streets is that it is not as good or reliable.

The problem is that the market leader is expensive, and needs that vacuum feed. Neither the inlet manifold nor the carburettor on the New Falcon has a vacuum take-off. Why bother, when you don't have to balance the carburettor with anything else?

It would be possible to make a vacuum take-off, by drilling a hole in the manifold and doing some careful work with Lumiweld. However, you would still be left with the expense of the chain oiler (and the worry that your vacuum take-off might break and either stop the engine or cause it to run lean enough to seize).

How about a 20 chain oiler, that needs no vacuum feed?

The main item is a drip-feed oiler. This is a very old design of oil delivery, used on steam engines. It uses a cylindrical reservoir with a spring-loaded spindle down the middle. The spindle is lifted by a knob at the top, and the oil allowed to flow out of the bottom of the reservoir. The height that the spindle is lifted is controlled by a nut under the knob. This is what provides the slow drip. The rest is plumbing.

Diagram of the drip-feed oiler

I obtained the drip-feed oiler from Axminster Power Tools. I bought the 40mm version, part number OL40. There is also a 30mm diameter version, part number OL30. The 40mm version cost me 16.92 delivered.

The bottom of the oiler is threaded 1/8" BSP. I bought a brass nut to fit the thread for 50p. The nut was intended for some sort of plumbing job, as it was threaded from one side, but had a small exit hole at the other.

To connect a small-bore tube to the oiler I needed a narrow pipe at the bottom. I used the end of an old brake pipe from a car. This was 5mm outside diameter, and had a flared end. I drilled the hole in the brass nut to 5mm, and dropped the brake pipe through. The nut pulled it up against the bottom of the oiler, and the flared end on the brake pipe gave me a seal.

I had a length of 4mm outside diameter clear plastic tubing in the garage. Warming the end with a match softened it to get it over the brake pipe.

I bought a 40mm spring clip for about 90p. I had an old P clip in the toolbox, and this provided some rubber strip to line the jaws of the spring clip. The spring clip then fitted over the body of the oiler.

I decided to mount it under the seat. There is a gap to the left of the battery, between the battery and the toolbox, that goes down quite a way. I fiddled with the oiler in its spring clip until I could lead the plastic hose down past the battery tray. When it was right I marked the side of the toolbox.

The tricky bit was transferring the measurement to the inside of the toolbox. In my case the rear end of the spring clip lined-up with the rear of the seat spring bracket, so I lined it up by eye and marked the inside of the back of the toolbox.

I drilled two 5mm holes, and mounted the spring clip on the back of the toolbox under the seat, using a couple of small BA sized nuts and bolts. I then put the oiler in its spring clip, and locked the jaws of the clip together with a plastic cable tie.

The final stage was to deliver the oil to the chain. The commercial chain oilers use a small pipe mounted so that it just touches the face of the rear sprocket. The centrifugal force of the spinning sprocket carries the oil out to the chain links, and forces it into them.

It was very likely that I would need to adjust the oil flow on my home-made oiler, and I was wary of covering the rear tyre with oil spray, so I decided to deliver the oil to the engine sprocket.

If you look at the flywheel / dynamo cover, there is a small gap just to the right of the bit that goes up to the dynamo, right over the engine sprocket. I led the plastic tube in through this gap.

View of the left side engine cover. The mounting bolt used to hold the oil tube is arrowed.

To hold it in position, I used the metal strip from the P clip (mentioned above). I wanted to use a short bolt coming in from the back of the engine side of this cover to hold a bracket. The plan was to use a very short bolt, and to cut short the 'proper' bolt that held the cover. However, the engine breather gets in the way. It is just possible to get a 12mm long M6 bolt in from the back. This held a short strip of metal with a 6mm hole for the bolt, and a springy loop formed to hold the plastic hose.

Plan view of the left side of the engine, showing the short mounting bolt position next to the breather (A) and the corresponding shortened bolt in the side cover (B).
Plan view of the spring clip with its bolt.

With a bit of fiddling I got the hose to line-up with the outside face of the engine sprocket. I searched the garage and found a bit of plastic tube that was a tight fit in the end of the hose. It was actually a spray nozzle tube for a tin of WD40. With a bit of careful heating from a match, I put a 90 degree bend in the end. This allows the oil line to clear the sprocket and chain, and brings the end in to rest on the face of the engine sprocket.

View of the engine sprocket.

I cut the end off the cover mounting bolt, and screwed everything back together.

So far, it seems to be working well. I filled the oiler with ordinary 20W50 to set it up and get the flow right. I then swapped to chainsaw oil when I was happy with the flow. This is a cheap alternative to the non-fling oil that the market leader chain oiler uses.

Copyright © Paul Friday

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