Starting a 1971 750 norton commando

My 74 850 has a Mikuni and tri spark ignition and starting technique is: enrichener lever down, both Petcocks on, kick slowly through compression(you can feel it), turn key on, one smooth kick, open throttle as bike fires. Well over 90% starts first kick or second. If not I turn off enrichener so as not to flood and 2-3 more kicks has it running.

I had a Boyer prior to the tri spark and it was a bear to start with kickbacks and lever just stopping as if engine locked up. I was ready to buy an Alton e-start due to pain to knee and ankle. Fitting the tri-spark with NO other changes transformed the starting.

Certainly having the bike timed correctly, new spark plugs, carb cleaned, battery charged, and fresh gas are essential to easy starting.

Have you checked your oil level? I know that my oil would often "disappear" (leak down into the sump). Then when I'd kick the bike, this slowed the rotation. Once I'd drained the sump, the bike would start first kick.

Fullauto said:

With a Mikuni, choke on, no throttle.

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This is a fine point, but very important. When you are coming down on the kickstart, make sure you don't tweak the throttle by mistake. It's easy to do when kicking. Opening the throttle makes the enrichener on the Mikuni not operate. I'd also add that most all single Mikuni Nortons I've started usually take two kicks to start when cold. A lot of the dual Amal carbed Nortons will start on the first kick.

Most electronic ignitions do not spark on the 1st revolution - that means you have to kick the hell out of it. Find one that does spark on the 1st revolution. Or you can install a Morris or Joe Hunt magneto (late model with neodymium magnets). With the mag and aftermarket carbs I generally get a start 1st kick.