Starting issue. Please look.

I would check the connections on battery are tight first and no corrosion, clean everything. The battery voltage at rest should be 12 and a half or above volts I believe and even then it may not have enough to start the bike if a cell is going down,it may be failing under load. What voltage do you get without engine running with lights on,this can tell you a lot? What is the voltage with engine running? I would try borrowing a good battery off a mate and see how that goes. You may have a charging issue too if it fails to charge after a good run but as it runs ok on a run maybe not. You dont wanna be turning the engine over too often with a low battery or you will do your sprag clutch in

just found this thread,it may be useful to you

http://www.triumphrat.net/speed-tri...-diagnostics-rectifier-regulator-upgrade.html

 

also agree with you about the fail rate of gel batteries, when they are good they are great, when they fail they give very little warning.

 

Battery does sound like main suspect. Get a load test done, friendly dealer should do this free especially if yer looking for new battery. Needle needs to go into green on tester. If not tester, suspect rectifier (won't push required volts out to battery to charge) I've had green on optimate BUT when load test done, not got above 8 volts. With engine running multimeter should show 12/13 even 14 volts depending on battery need. Good luck

 

Agree with Recycled Rocker - had same problem with the Bonnie - always showed the green light on my charger, but not enough juice there to fire the motor up. Probably looking at a new battery - mine was supposedly only 16 months old. Not an issue with the Bonnie but watch out the sprag clutch on yours.

 

I agree with the above but also check the starter earth connection.
Keith