Uncle Norm fixin the nephews machine

[Norm]

My nephew had been talking about his motorcycle and needing to have it looked at as it quits running frequently.  Knowing he is a great artist but lousy mechanic that doesn't maintain any machine well - I picked up the bike and hauled it home yesterday. 

The bike turns out to be a Bridgestone 90 sport with 530 original miles on it!  Pretty much all original.

His complaint was that when he moved the switch to lights - the machine would stall.

Here is what I know after looking at it for a day:
* the battery was toast (when I went looking for a replacement, I ran into a guy who worked for the outfit that bought the last Bridgestone dealer  in Washington, I'm not clear if he ever sold them but he was clearly very knowledgeable).
* it likes to have a shot of starting fluid to get running - I tend to use it to differentiate if I have an ignition issue vs a fuel issue. 
*it does stall at strange times - I'm still not clear if it is an ignition stall or a fuel stall ANYONE KNOW OF ANY COMMON ISSUES THAT I SHOULD LOOK FOR??
*DOES ANYONE HAVE IDEAS ON HOW TO ADD MIRRORS WITHOUT "MESSING UP" THIS ORIGINAL EQUIPMENT BIKE?
* I did take the exhaust off and clean it and the liner as best I could I USED FIRE/HEAT ON A PREVIOUS 2 STROKE TO ACCOMPLISH THIS - WHAT IS A BETTER WAY SO I PROTECT THE CHROME?
* I checked the plug but haven't gotten to the points yet, nor have a checked the charging/ignition system

Ideas are welcome!
Thanks
"Uncle Norm"

[reed]

Norm,
Welcome to the site, on your Bridgestone 90 you will need a new battery.
Clean fuel, and i would take off the carb to be cleaned.
Check out the points and plug because once you get the Bridgestone running
You can check the charging system .The baffel at the end of your exhaust
Comes out to be cleaned with a wired brush and you can use heat etc.
If you need points i know Richard has them and check him out for mirrors.
Thanks.
Steve.

[Bikenstein]

Welcome to the site Uncle Norm. Also you might want to check your air filter.

[disc_valve]

Hi, Norm,

From my experience of machines like the BS90 that uses a flywheel magneto, if turning the lights on causes the bike to stall then it's almost certainly points and plugs. Fit a new B8HS plug, and try cleaning the points and gapping them to 0.015". If the points are pitted, then throw them in the bin and fit a new set. Richard should be able to supply new points.

While you've got the wrenches out, it's worth while taking the carb apart to clean out the float bowl and make sure the main and pilot jets are clear.

The battery on the bike is only used to power the stop lamp, neutral lamp and horn. The engine will run quite happily without a battery, and headlamp and tail lamp run directly off the magneto. It's probably a good idea to fit a new battery (otherwise the lights will dim as soon a s the stop light is activated - not good!), but a dud battery shouldn't be tha cause of your current engine problems.

Hope that helps,

Graham