No spark 1970 Triumph Bonneville

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captainc2

Member
I purchased this bike not running, the guy I bought it from said he couldn’t get fire from one cylinder. So I am in the process of tracking down the problem, left side plug has no fire all Lucas components. I’ve checked and cleaned points, with test light on points no current on that side. I have swapped coils and it tested fine, plugs and plug wires test good. Any Ideas???
Thanks
 
I’m New to Triumph.
Guys what am I missing? I now have fire at both plugs, tickle carbs have fuel, bike backfires from both sides exhaust. Can not get it to start.
HELP!!!
 
I’m New to Triumph.
Guys what am I missing? I now have fire at both plugs, tickle carbs have fuel, bike backfires from both sides exhaust. Can not get it to start.
HELP!!!
There is a lot of missed history here, .
Triumphs at that time simple had twin points setup.
It could simply be some one has had the timing cover off and not set it it up again.
To find out how it is set up.
Remove the cover from the right hand side , its a small round plate.
In there there's these things called points, one per cylinder.
Your going have to learn about these electrical devices , but a quick check that there opening and closing is good enough for now.
Utube or internet can explain about points and spark systems.
Take the spark plugs out and set the pistons at Top Dead .Centre.
Look down the spark plug hole, you should see on one cylinder the valves open. The other cylinder is the one that has gone bang at this point. So that's the one that should have the points open. If not the plug leads need swapping over.
But then everything could MBE just fine in the electrical. department.
petrol now!a days is so bad , it might need a carburetor clean.
Let others tell you about that.
I believe an American said " if all else fails , read the instructions "
Try the Library.
Chris
 
Thanks Chris for the reply! Here’s where I’m at, new plugs, New points set at 15 thou, new condensers, adjusted valves, I rebuilt both Amal 930 carbs, just set static timing. At TDC the points are open on the opposite side. ???
 
Thanks Chris for the reply! Here’s where I’m at, new plugs, New points set at 15 thou, new condensers, adjusted valves, I rebuilt both Amal 930 carbs, just set static timing. At TDC the points are open on the opposite side. ???
Make sure you cleaned the tank and didn't fill them rebuilt fuel with old fuel / water.
Never use " start you bastard " Aerosols or equivalent.
Bike s catch fire !
You can hand spray a little bit of fuel , with a plastic bottle , but only once.
If opposite points is open , then switch ht leads.
Remember FUEL. , AIR. , SPARK. that's all there is to it.
Make sure that SPARK IS GOOD.
Don't work late at night.
 
Make sure you cleaned the tank and didn't fill them rebuilt fuel with old fuel / water.
Never use " start you bastard " Aerosols or equivalent.
Bike s catch fire !
You can hand spray a little bit of fuel , with a plastic bottle , but only once.
If opposite points is open , then switch ht leads.
Remember FUEL. , AIR. , SPARK. that's all there is to it.
Make sure that SPARK IS GOOD.
Don't work late at night.

Thank you Sir!
Switched plug wires and she started the first crank.
 
The gas we now have is not user friendly. I use non ethanol in all my vehicles that are not run daily. That includes generator, motorcycles (even though I drive them daily), lawn mowers, pressure washers, chain saws, wood splitter, wood chipper, leaf blowers, weed whackers, tiller, 1953 Chevy Hot Rod Show truck, etc. That just about does it. I also use Seafoam and Star Tron in all my vehicles. During the winters I lower the gas levels in the equipment that I do not use during those months to almost empty and add Star Tron to that mixture and run each piece of equipment for 10 minutes to get the gas down into the carbs. I use to run them all dry but then found out that they are better off having gas in them. That is also another reason I use non ETOH gas. The alcohol will leave a green film inside the carbs and will stop up all the very small holes. What I do may be overkill but I have yet to have one of my engines not fire up and run.
 
The gas we now have is not user friendly. I use non ethanol in all my vehicles that are not run daily. That includes generator, motorcycles (even though I drive them daily), lawn mowers, pressure washers, chain saws, wood splitter, wood chipper, leaf blowers, weed whackers, tiller, 1953 Chevy Hot Rod Show truck, etc. That just about does it. I also use Seafoam and Star Tron in all my vehicles. During the winters I lower the gas levels in the equipment that I do not use during those months to almost empty and add Star Tron to that mixture and run each piece of equipment for 10 minutes to get the gas down into the carbs. I use to run them all dry but then found out that they are better off having gas in them. That is also another reason I use non ETOH gas. The alcohol will leave a green film inside the carbs and will stop up all the very small holes. What I do may be overkill but I have yet to have one of my engines not fire up and run.
Glenn, I agree with you 100%. I, too, run non-ethanol gasoline in all of my small engines and run it in my 68 Trophy. Most of the time, I use it in my Tiger which I ride nearly everyday.
 

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