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Discussion Starter · #1 ·
Has spark , getting fuel, timing is right on. Back fires through throttle body and exhaust. 150 compression both cylinders, new battery and plugs. ECM good, crank sensor good. Any ideas?
 

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The Vic shop has some good videos
 

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Any chance you have the plug wires reversed?

Did you buy it like this?
Was it running fine then all of a sudden had problems ?
Have you changed anything at all before the problems started?

I am curious as to how you checked timing, the ECM & the crank sensor?
 

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Discussion Starter · #6 ·
Any chance you have the plug wires reversed?

Did you buy it like this?
Was it running fine then all of a sudden had problems ?
Have you changed anything at all before the problems started?

I am curious as to how you checked timing, the ECM & the crank sensor?
I have a second bike same year just like it. I tried the parts from the one that doesn't run to the one that runs and bike ran fine with the swapped parts.
 

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Discussion Starter · #7 ·
Any chance you have the plug wires reversed?

Did you buy it like this?
Was it running fine then all of a sudden had problems ?
Have you changed anything at all before the problems started?

I am curious as to how you checked timing, the ECM & the crank sensor?
Yes I bought it this way. History is..... to many hands have been on it.
 

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I have a second bike same year just like it. I tried the parts from the one that doesn't run to the one that runs and bike ran fine with the swapped parts.
So which of the parts that worked, don't work when you use the old part?
 

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Yes every part I've tried works on the running bike. It acknowledge like the timing is way out. Checked timing it's right on. Checked valves and compression. Both good, com 150 both cylinders.
How are you checking timing
AND
Are you checking "mechanical" timing (cam to crank) & ignition timing?
 

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Step.1. Is it turned on?
Kidding. Any chance the spark plug cables are reversed?
 

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Ignition timing? There's only one way to set timing, mechanical. Right?
I'm not that familiar with Vic's But something has to tell the coil went to spark at the correct time.
Crank position sensor on cars plus ECM looking at "other stuff".
Gotta find out what controls spark.
 

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I'm not that familiar with Vic's But something has to tell the coil went to spark at the correct time.
Crank position sensor on cars plus ECM looking at "other stuff".
Gotta find out what controls spark.
The ECU controls the spark, but the timing wheel is the crank position sensor to let the ECU know, or believe, that the crank is at TDC. The wheel on the Vic can be re-positioned, hence altering the timing, but the ECU also changes timing, advancing or retarding, depending on the readings. It does supply signal for spark, but it needs signal to spark. Without signal, it won't spark (failsafe).
This one is already sparking and getting fuel according to the OP, which muddies the waters unless it's got an adjustable timing wheel that's slipped it's position but OP says that's been checked as well.
 
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