I'm new to Norton's. I just purchased a '72 750 Commando Roadster that's been restored. The guy I bought it from put in a new electric ignition but it's still hard to start (doesn't help that I'm a litle guy). However, when I first got it back home and started it up I noticed a significant amount of white smoke coming from the chaincase where the alternator is located. At first I wasn't concerned as I thought it was just oil burning off the muffler or chaincase from the ride home. I rode it around the block a couple of times and it was running ok. I got back home and shut it off and then restarted it after it cooled off and the white smoke seemed worse. I noticed it stopped smoking after it ran for about 10-15 mins. The ignition was in the Ignition & Lights position. But when I switched it to the Ignition only position it killed the engine. Is that normal? I toggled the key from position to position and when I did this a big puff of white smoke came from where the air filter is located. When it did this is made a "swooshing" sound. That made me worry. It was enough smoke that I thought something was on fire. Since then I've started it and ran if for a few minutes. I've noticed the lights getting really dim and the brake light was so dim you couldn't see it at night. I checked it the next morning and the battery was completely dead. Now it won't fire. Any ideas on whats going on? What should I do?

Seems to be to many swooshing sounds and smoke from to many places. First Do you have oiling system problems? Drain your engine before you start. Combats have a single 9/16 bolt as the sump drain. Make any difference? Make certain you are not wet sumping (do search of this sites archives on wet sumping). Excessive oiling to top end? Rocker shafts put in wrong? Only top off the oil tank imediately after you run..... not after the bike sits for days.... Puff of smoke out the intake valve/carb is when electronic ignition sparks a charge off when you switch the IE box from off-on. Sounds like the restorer is not good at breifing you on the condition of your bike or in it's proper use. It won't be the first time I've seen/heard of a "restored" bike turn out to be very deficient in a whole variety of quality issues....

The smoke wasn't coming from the primary case after all. It was from the oil dripping on the hot muffler. I still haven't found out what the swooshing sound and smoke from the air filter was from. Nevertheless, the bikes running really good and strong.

The combat breaths out the back of the crankcases from the adaptor. It runs up the big diameter hose to the top and into the top of the oil tank. A seperate hose from a different fitting then is routed to the air filter backing plate. The air running into and out of the bottom end makes the sound as the pistons go up and down. Sometimes a wet gurgling sound while kicking....

the swooshing noise is the ignition fireing when you turn the key off and on, it has also spatt back out the carb,henc white smoke out of your air filter.Your battery is either stuffed or flat,engine died when you turned the lights on. Boyers may start and run with dieing charging system but they don't work well,mine would surge and when it got really flat you could here the ex note was off.