New engine chirping and running on 2 cylinders | Page 6 | GTAMotorcycle.com

New engine chirping and running on 2 cylinders

Ha! Re-flowing a single solder joint at the PCB fixed the diode, I now get a reading at the pins.

Let's see what the bike says.
 
Well... the whirring seems to be gone for good but the misfiring remains. Am airing out and cleaning plugs 3 & 4 to eliminate the risk of fouled plugs.

I notice that the FJ uses a sidestand relay whereas the Radian connects the sidestand switch directly to the igniter... should I try to remove the relay and replicate the Radian's simpler setup?




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Glad you fixed the whirring sound.

Do the plugs smell of gas when you remove them? Can you smell gas down the spark plug holes? I clean fouled/dirty plugs with electrical contact cleaner and let them dry out.

And have you tried starting it with kickstand up, neutral, with clutch pulled in?

When you have started it previously, does it only start with choke on? How about choke off?
 
Plugs 3 & 4 do smell of gas, and I do smell gas down the spark plug holes after running her on two cylinders for ~10 seconds.

And yes, I believe I've tried every combination - sidestand up with bike on centrestand, sidestand down with bike in neutral, sidestand down with bike in gear (no start), clutch pulled in, clutch not pulled in, etc. When it does start, it's always only on cylinders 1&2, and there's this chirping sound if I try to rev up.

Bike currently starts without the choke on. As in, I haven't had to try using the choke. FJ's engine behaved similarly - it only needed the choke in sub-10c temps.

I'm surprised it starts at all with only two firing cylinders.
 
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If you were to pull all the plugs and compare the strength of the spark of 1&2 compared to 3&4 (another chance to use the slow-mo feature on your phone?)...how do they compare?
 
Bear in mind that cylinders 1 and 4 are getting spark from opposite ends of the same ignition coil and there is only one 12V ignition-fire signal going to that coil, and likewise for cylinders 2 and 3.

If 4 is not firing but 1 is, the problem is not on the low voltage side of the ignition system. It could very well be bad coils, plug wires, or plug caps. If you can swap 2 and 3 (Keep the plug cap and ignition wire and coil connections intact, just swap the entire thing over) try that.
 
That's been done already Brian (look back at older posts). 2 and 3 were swapped and still only cylinder 1&2 would run.

All 4 plugs have spark.

Trying to establish now if spark strength is strong across all cylinders.

We've already established alternating spark on 3 and 4 which suggests spark timing is occurring at 0 degrees and 180 degrees.

Plugs 3&4 are wet from fuel.

So 3&4 get fuel and spark...which would then lead us back to carb setup.
 
Thanks for chiming in Brian. i've tried that already, even cut/crimped brand new spark plug wires to eliminate that variable.

Robbo - good idea, will make a vid of 1 & 2 this morning and compare.


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Hmmm, so I just took one step back, but I think I'm getting closer to the solution. Now I get one spark then ignition gets cut off. Going through the starting circuit troubleshooting in the manual, the sidestand relay tests out fine when connected directly to the battery, but when connected to the bike and with the ignition turned on and kill switch to RUN, it alternates between continuity (0 ohms) and discontinuity (∞). The wire that runs from the relay to the CDI shows continuity so it's prolly not the culprit.

Battery is on the charger for now, will resume troubleshooting once it's back to full.
 
It's looking more and more like my issues have nothing to do with the "foreign" Radian components, and everything to do with the existing, aging wiring.

Sidestand switch was iffy on the multimeter, showing hundreds of ohms at times and only intermittent continuity. I cleaned it real good and activated it several dozen times and it's behaving normally now.

If that was the cause of the misfiring, I just might ban myself from this forum. Online seppuku.


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Been busy and/or out of town a lot so haven't had much time to work on the bike, but I just realized something... both the Haynes and Clymer manuals claim that the 89-90 Radians should have 1.8 to 2.2-ohm ignition coils. The current ones are 3-ohm Dynas... Also, the previous owner was using his Seca's coils, which are around 2.5 ohms. Which might explain why he was able to run on all four cylinders but not me?

What issues would arise from using a higher resistance coil? Weak spark I assume? Could that also cause current to somehow "back up" in the system and, say, spin the starter back up a couple seconds after initial engine startup? :shock:
 
Maybe it could mess up the CDI? I know what CDIs do but I don't exactly know how they do it. Personally don't think it could hang the starter
 
Has it *ever* run correctly on the Dyna coils that you have on there now? Has *any* engine run correctly with the Dyna coils that you have on there now?
 
Has it *ever* run correctly on the Dyna coils that you have on there now? Has *any* engine run correctly with the Dyna coils that you have on there now?

Previous engine ran perfectly. This bike has been a near-daily driver for the last 4 years.

But no, never ran correctly on the new engine with the new '89 Radian TCI.
 
Finally fixed her last night - starter was misaligned which I guess made the starter gear and sprag clutch bind. One of the starter mounting holes was cracked. Anyway, I replaced it with a newer starter and all is well. Running on all four and no more smoke show at startup. :cool:
 
Sweet. Gotta love it when it all comes together.

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What a machine.
 
Nice
 

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