Rotary Owners' Club

Try unscrewing the plug caps from the HT leads to check if you have a good connection. Check the bolt where all the negatives are fixed to the frame near the regulator. Do you have full voltage output from the alternator and regulator?

When the engine reaches around 60 degrees, the ignition unit retards the ignition below around 2000 rpm to control the tickover so it sounds like the problem is on the fuel side, try balancing the cabs at tickover. A full carb strip down and clean will be the best option. Oil accumulating in the car...

Good news. If you are going to leave the bike idle for a while, try the old two stroke method of turning the fuel tap off a quarter mile from home. That way the float will be open with fresh petrol when you turn it back on.

The exhauast has a ballancer pipe on the manifold, this means the non running side eventually warms up and gives the appearance of running on both chambers. The cold side is the faulty one which helps to narrow it down.

I've had the problem with my Commander. Turned out to be a float needle sticking closed. If you do not want to dismantle the carbs, try to loosen the 4 screws on the bottom of the float chamber to see if fuel is present. Remove the fuel pipe & squirt carb cleaner or Redex into the carb & tap...

If the engine ticks over on both sides but cuts out on left side at small throttle openings, try removing the plastic pipe that drains the frame into the left inlet tube. Blow down it and listen for bubbles in the frame, the bottom of the tube should be in oil. That could be where the air is getting...

Minimag light sequence, engine stationary Red light on - side stand down. Red flashing - ignition on, engine stationary Red and Green on - engine warming up. Engine warm and running No lights on -engine running Green -engine speed 1000 to 2000 rpm Red on - rev limiter 9500 rpm. If you have faulty HT...

I had to file the holes to get mine close enough to pick up a signal. When you get the ignition sorted you can look forward to hours of fun setting up the carbs. I've had my Commander for 28 years, sometimes it just sulks for no obvious reason and decides to cut out at traffic lights after running p...

Make sure that the plug caps are 5000 Ohm suppressed, 10,000 at the most.Remove the plugs and earth them to the fram so you can see the spark. On the three pin plug with brown,yellow and white wires, connect a 12 volt 5 watt test lamp between negative and the yellow wire, the lamp should glow. Spin ...

I bought my Commander in 1996 and always used 4 star. Now I use BP Ultimate with Castrol Valvemaster. 140,000 miles later and still 54mpg. E10 is not worth the risk.

Is the problem only when the engine is hot ? Sounds like it could be an air leak. Make sure the idle pipes are fully into the engine casing, a light tap with a blunt screwdriver will do. Try a smear of instant gasket around the pipe to see if it helps. If your bike has the crank case drain modificat...

Is the oil pump set correctly? Long downhill runs on a closed throttle can cause plug fouling.

I am that rider. I live in Horncastle and have owned the bike since 1996. She now has 130,000 miles on the clock, still on the original chain and sprockets. A new voltage regulator and ignition unit repair were needed last year, but generally reliable. I clean the carbs vacuum chambers as soon as th...