Model 50 timing on a retarded setting

A model 50 in low state of tune is more forgiving to timing than some motors. arriving at 1/8th btdc is not easy though. On my Dommy I just advance the timing till it trys to kick me back then back off till it behaves!!. I do the same with my 10,000 rpm ohc single and its never been a problem -----up to now!.

In an old book, I read 17.5 mm BTDC, fully advanced. Probably your decribed method will work. To me it seems that best performance will be when you adjust timing at a fully advanced setting. Hopefully someone else will have more thoughts about it.

Mike

I think that your 1961 Model 50 will be contact breaker ignition, not magneto. The atd range may have altered over time, to the fully-retarded position can't be taken for granted. It should ideally spark at 4 degrees BTDC retarded. I would suggest doing the timing disc thing while you make sure your ignition is working to specs, and then find a short-cut such as something down the plug hole.

Paul

Here is a low-tech method I have used in the past on my 1961 Model50:

Cut a piece of coat-hanger wire about 6 inches long and bend a 2 inch bend in one end. (this will keep it from falling into the cylinder)

With the plug out find top dead center on the compression/firing stroke. Put the wire in the hole and mark the wire at some suitable fin or edge of the spark plug hole for reference. Then mark the wire 1/8" above the previous mark.

Put the bike in gear and by rotating the rear wheel backward find where the new mark meets the same reference fin, etc.

Then loosen the distributor body and rotate it until the points are fully closed. Place a piece of thin paper between the points and rotate the body just until the paper pulls free. Lock the distributor body down and you should be good to go. Re-check if you feel the need to.

Later in life I made a degree wheel and marked the alternator rotor and body so I could use a timing light but it is always messy taking off the primary cover.

The Model 50 is a great bike. Treat it well and it will give you years of service.

Mike

Paul's right about the ATD - the stops wear. Time it up fully advanced, stick a washer under the cam securing screw to lock it. Get an old spark plug and knock the ceramic insulator and electrode out of it. Tap it 5/16 thread (I think - check) and run a stud through it. Screw the plug into the head and screw the stud in until it stops on the piston. Lock it off with a nut. You now have a tool to set your timing without having to go to the hassle of the timing disc route.

Regards,

Ian.

Hitchcocks, the Royal Enfield suppliers, do an excellent TDC detector tool for only £8+ VAT. Catalog number is E0003 under tools Universal, page 264-5 of their online catalog. www.hitchcocksmotorcycles.com ,tel. 01564783192.

I have found the trial and error method described to be the most suitable for my own m50.timing as per recommendations should give perfect ignition and performance but age,wear etc has to be factored in,plus the poor fuel we now have to contend with all conspire to rob us of what limited performance the m50 has.

If you advance until it kicks back or spits then you have gone too far. So long as it starts easily I find that the timing is then good enough.

Hi Henry

On my 1960 M50 I tried the methods described by others in your replies, and all worked well, but the best results were at full advance and with a degree disc. I also found sometimes, after 'blipping' the throttle (twist grip) the engine sometimes took a while to settle down to a steady tick over. This problem was solved bythe fitting of a new set of springs to the distributor advance and retard mechanism,,,,,,,,,,,,,,,,,

Regards John O