Triumph Rat Motorcycle Forums banner

1 - 9 of 9 Posts

·
Registered
Joined
·
6 Posts
Discussion Starter #1
Hey all.

Well this has stumped us, we've had the magneto out in the vice (fitted with a easycap C01) and it has a brilliant spark on both sides of the points, also tested the spark plugs whilst magneto was in the vice and getting a spark from them both sides. So we when install the magneto back into the bike we get the same spark from the points, but none in the plugs, even put my finger in the leads without being shocked.

We're stumped by this, magneto seems to working fine, we've tried leads and plugs from a different bike (T100 pre unit) that we know work and still nothing. We've also tried a different set of points with another easycap C01 installed, get an even brighter spark but nothing at the plugs again, something being ground out?

I've heard these pre-units can be the masters of disguise for problems like this....living up to its name, any thoughts on what could be the issue?

I'll provide a video of the sparks in the points and plugs to show whats going on tomorrow.

Cheers
 

·
Registered
Joined
·
1,222 Posts
1.When you turn it in the vice and it sparks, are you turning it in the same direction as it does on the bike? I know it’s a bit simplistic but we all make obvious mistakes sometimes.

2. If you have the mag fitted to the bike with no drive pinion, does it spark when you turn the armature shaft? I’m just wondering if a bad slipring or something is letting the HT leak to the armature (or something!) and the path is then through the mag drive pinion and camshaft gear.
 

·
Registered
Joined
·
6 Posts
Discussion Starter #3 (Edited)
Hey Thrashr, yeah double checked that and we are turning it the same direction as it would in the bike.

Haven't tried it without the drive gear on the armature, good shout! Will give that a try tomorrow and post an update. I've also swapped out a mag that I know works into the T110 so will also give that a try tomorrow once I've timed it again.

Video of the points and spark plugs on the bench

 

·
Registered
Joined
·
1,222 Posts
I may not be seeing the video all that clearly, but I think you should see sparks at lower rpm than that. That doesn’t look like kickstarting rpm.

Also, the sparks at the plugs don’t look all that regular.

The spark should jump 1/4” from the end of the wire to the case.
 

·
Registered
Joined
·
6 Posts
Discussion Starter #5
Quite hard recording one handed and camera's not the best but the points do spark at lower rpms consistently, spark plugs seem to be sparking randomly, no consistency but at least there's something there compared to when on the bike. Tried out different leads, pickups and spark plugs but still create very erratic sparking, could be my bench setup is a bit ragged as they seem to be sparking bright and consistently on the T100
 

·
Registered
Joined
·
6 Posts
Discussion Starter #9
Eyy so tried out the other magneto in the T110 and it works! Spark at the plugs, must be something wrong with the first mag we tried, will be stripping it, cleaning it and giving it a go again.

Next issue is fuel pissing from every possible place on the carb, will be having a go at that, then timing and seeing if it'll start. Will keep you all updated

Edit: bit more info, the mag that work has a condenser that works and no easycap installed. Good old electronics
 
1 - 9 of 9 Posts
Top