Danieljohn Posted March 12, 2018 Report Share Posted March 12, 2018 Hi guys I have a 96 beta techno it’s running backwards il give you the long story I used the bike a few weekends no issues went out a few weekends ago the bike started reving flat out I cut the engine out with the kill switch then restarted the bike continued to use it for a few hours no issues came home washed it, I pulled the bike out this weekend started it, it didn’t sound right it was backfireing and going backwards in gear. Also became difficult to start I’ve checked the crank woodruff key cleaned carb and reeds I’ve tryed moving the stator plate both ways still going backwards any 1 else had a similar issue it’s drivin me mad thanks. Quote Link to comment Share on other sites More sharing options...
bikestat Posted March 12, 2018 Report Share Posted March 12, 2018 ignition timing needs setting common problem on two stroke motors 1 Quote Link to comment Share on other sites More sharing options...
Danieljohn Posted March 12, 2018 Author Report Share Posted March 12, 2018 Hi thanks for the replay would I be correct in saying the timing adjustment is on the back of the stator plate? Would you have any timing settings thanks again Quote Link to comment Share on other sites More sharing options...
section swept Posted March 12, 2018 Report Share Posted March 12, 2018 (edited) If the ignition timing has altered you need to find the reason why. If the stator plate has not moved, and the woodruff key is good and there is no excess play in the key way...you don’t say if the key way is good. Why did the engine run away, was the throttle slide stuck? Not sure if your electronic ignition unit has an advance map or not, still if it was faulty I doubt it would retard the ignition enough to cause reverse running.? Edited March 12, 2018 by section swept Spelling error Quote Link to comment Share on other sites More sharing options...
copemech Posted March 13, 2018 Report Share Posted March 13, 2018 sheared woodruff key, need a flywheel puller now! Quote Link to comment Share on other sites More sharing options...
dan williams Posted March 13, 2018 Report Share Posted March 13, 2018 2 hours ago, copemech said: sheared woodruff key, need a flywheel puller now! Most likely scenario. Quote Link to comment Share on other sites More sharing options...
Danieljohn Posted March 13, 2018 Author Report Share Posted March 13, 2018 hi I’ve removed the flywheel cleaned the stator pickup and flywheel replaces the woodruff key old 1 wasn’t snapped just replaced it as I had some still have the issue Quote Link to comment Share on other sites More sharing options...
scifi Posted March 13, 2018 Report Share Posted March 13, 2018 (edited) It could be old or low octane fuel, causing a bounce back, by igniting before TDC. I used to fly model aircraft, and some glow-plug engines could be more easily started by bouncing the propeller backwards against compression, it would fire well before TDC, kicking the engine forwards. . Edited March 13, 2018 by scifi 1 Quote Link to comment Share on other sites More sharing options...
feetupfun Posted March 13, 2018 Report Share Posted March 13, 2018 I'm not familiar with a techno flywheel so can anyone say if it is feasible that the cup of the flywheel has moved relative to the hub of the flywheel? Another thought was is it possible that the magnet that triggers the spark may have lost its magnetism somehow and so the spark is being triggered by the wrong magnet? Quote Link to comment Share on other sites More sharing options...
feetupfun Posted March 13, 2018 Report Share Posted March 13, 2018 (edited) Just had another thought. Check for "poling". This is where one or more magnets touches the stator laminations. Can be caused by play in the main bearings, poor alignment of flywheel on the taper, loose stator screws, loose magnet/s Edited March 13, 2018 by feetupfun Quote Link to comment Share on other sites More sharing options...
dan williams Posted March 13, 2018 Report Share Posted March 13, 2018 If it isn't the woodruff key then something is very odd indeed. Typically the electronic ignitions are difficult to get running backwards unless something is not connected correctly in the wiring. The trigger coils are only pulsed by two special magnets in the flywheel that have their fields oriented 90 degrees off from the rest of the magnets in the flywheel so even if something were wrong with the coils they can't be triggered by the other magnets. A missing/broken ground can cause transient signals to be generated that can fool the CDI into thinking it has received a trigger signal. So the next thing I recommend is checking your ground connections. After that would be go through your wiring to make sure connectors are not in bad shape. Not on a Beta (Armstrong/CanAm) but I did have a bike where the wires from the stator to the CDI were swapped at the factory. The bike never ran great but it ran and occasionally it would run backwards. Took me two years to figure that one out. If your wiring is intact I'm thinking your CDI box which has a microcontroller in it may be on the fritz. In general the starting position for the stator backing plate on a Beta is in the middle. Please let us know if you find the root cause. We're all learning here. 2 Quote Link to comment Share on other sites More sharing options...
reggie Posted March 14, 2018 Report Share Posted March 14, 2018 Perhaps this particular bike is one of the ones that needed the offset flywheel key Beta p/n 1246010 000 to get the timing advanced far enough. GOOD LUCK ! Quote Link to comment Share on other sites More sharing options...
Danieljohn Posted March 16, 2018 Author Report Share Posted March 16, 2018 Hi bit of an update on my bike I have only got 5v coming out of my stator going to my coil which is very inconsistent my earth is also bad going into my cdi I’m going to look at my options of either getting My stator refurbishd or finding a breaker who can supply me with a used 1 does anyone have any contacts for breakers or someone who refurbishes these at reasonable cost many thanks for all your help through my nightmare ??Much appreciated. Quote Link to comment Share on other sites More sharing options...
bikestat Posted March 16, 2018 Report Share Posted March 16, 2018 allens used trials spares should be able to help richards contact number 07917 406313 Quote Link to comment Share on other sites More sharing options...
2stroke4stroke Posted March 17, 2018 Report Share Posted March 17, 2018 I'm not a gambler, never having placed a personal bet in a bookies, so wouldn't be inclined to take a punt on a stator from a breaker. At least a professionally sorted one will work, and for a reasonable time. Quote Link to comment Share on other sites More sharing options...
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