No spark on #2 cyl 900cc VMAx

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Vincent Maxwell Ribaldry

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I put one of G's COPs kit on my bike never rode another VMAX other than mine but I don't think it's making full power (I don't think it ever did).

Smells rich

If this is correct orrientation

front
1 4
2 3
back

I just did a shotgun on the carbs and sync'd.

I don't beleive this is a new issue post carb cleaning and sync, I was trying to correct it by focussing on carb issues.

Pulled all the plugs before leaving for work and all good but but on 2 which was wet and fouled.

Strong smell of gas, no leaks detected.

I guess other than checking for spark in what order should I start looking at other items. I haven't tried swapping cops yet, which I will also do tomorrow.

Sean
 
Correct cylinder numbering is:

Front
2 4
1 3
Rear

You need to make sure it is firing on the LH rear cylinder which can be established by feeling the exhausts (but not literally!).

Check that it is sparking by inserting another plug into the COP and turning over with the plug earthed.

If it is sparking then investigate possible flooding of that cylinder.
 
What is a "900 cc" VMax?

.......1/4 of 1200cc not working........900cc.

...before jumping on the ignitor box possible fix (last resort), make sure #1 cylinder stuff is working correctly. Swap all your electrical stuff from #3 over to #1 (including coil) and see if problem stays at #1 or goes to #3.

Also something like your main jet could have fallen out and causing a carb prob (or something simular)
 
What is a "900 cc" VMax?

A bit of good-natured sarcasm going on here, methinks.
1200 divided by 4 = 300, 300 times 3 (number of firing cylinders) = 900
Therefore, a 900cc max!
Keep in mind....I did all these calculations in my head.
I'm a bit of a mathematical genius.
Cheers!
 
I installed a new Dyna ign box only to find it to be faulty at idle it droped #4 cyl installed the factory ign box, fixed.
 
Kathy and I were riding the Blue Ridge Parkway back in 1988, and we hit a torrential rainstorm. The Max almost instantly became a 600cc Vmax, but after we got out of the rain and things dried out a bit, it grew from 600 to 900 to 1200cc's in just a few miles..
 
I had the same symptoms a while back. Turned out to be pilot air jets. Seemed like no spark swapped things around with no change so I did the shotgun once still no change did it a second time and has been running great for 3000 miles. I had the same wet plugs so first thought was plug or coil.
 
Recap:
All stock except:
Cobra exhaust
COPs kit
Bypassed crimp and direct wired R/R to the battery.
Carbs-changed main jets to 147.5 main jets previously to try to resolve the heavy gas smell that I thought was brought on from Cobra exhaust.
Lifted rear end about an inch with zrx1200 shocks.

#1 cyl was fouled out when I pulled the plug.

#1 cyl seems to run colder than all the other cylinders. Verified with a thermal imaging camera.

Smells super rich at idle.

Pops and snaps when not under load. I.e. idle and coasting.

Verified power on both lines to COPs.
Will this rule out a TDI issue?

Cleaned the plug up and swapped to 3 cyl.
No change.

Swapped COP to cyl 3
No change.

-Fiddled with the tdi wire connections.
Sounded like it was running smoother, prob in my head. 1 cyl is still cold.

I'm going after another shotgun.
I'm leaning towards a stuck or bad float or just done garbage in the carburetor.

Will also test wires to TDI for continuity.

Try to get rid of Cobra exhaust ASAP.

Sean
 
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I think there is a constant feed to the coil or COP and it is the return that is interrupted to generate the induced current.

Have you tried to see if the plug is firing on #1? Until you do this you are guessing at the cause.
Easiest way is with another (earthed) plug in the COP. If no spark swap the rear COP's over and re-test.

What you are trying to do is base you diagnosis on fact i.e. eliminate the possibilities and move on.
 
I think I got it with another shotgun. All cylinders are running up to temp. I think I need a new exhaust ASAP though to actually be able to tune it right.

Sean
 
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