Low on power, pulled the plugs...

Hey there..still pretty new to figuring things out as my 2007 GRiSO gets slowly sorted out cosmetically and mechanically with help from GuzziSteve, Youtube and this forum.

Several weeks ago, on a trip home, the bike was sputtering and massive loss of power, so I went to work. I pulled the plugs and gave them a look as I checked and adjusted the valves.
I could tell (via my TDC chopstick there was a decent amount of soot on the cylinder head and both plugs (that I have very few miles on) were pretty dark.
Valves adjusted to spec, cleaning the plugs and poured in some Seafoam with a fresh tank to trouble shoot.
Ran fine around the neighborhood...but yesterday, I went into the mountains north of me ..seemed fine but power output on the way home was strange.
The bike had no toque...I could eventually make it to the speed I needed, but it took forever to get there...and by the time I got home it was really bad, but idled just perfect.

So today I pulled the plugs again and took pics.

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Right cylinder had pretty wet threads also.
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I am not sure where to start actually and have begun searching for possible fixes to what may be a fueling rich issue?
Any advice from the GRiSO Sages?

Check your coil connections to the right cool. Power, ground, and both ends of the plug wire. Looks like weak spark, probably the plug cap.

Did you figure it out James? Spark plug wires do pullout of coils once in a while. They also short out too.
I would do normal checks, air, fuel, compression. I'm still available anytime. You could also see if anything shows up in the dash, maybe it threw a code. Just go t menu and then diagnostics put in the # on top of this site & check it out.

GuzziSteve wrote:

Did you figure it out James? Spark plug wires do pullout of coils once in a while. They also short out too.
I would do normal checks, air, fuel, compression. I'm still available anytime. You could also see if anything shows up in the dash, maybe it threw a code. Just go t menu and then diagnostics put in the # on top of this site & check it out.

Thanks Steve! I will check to see if the connections are solid at the coil and check codes when I get home. I did order a new coil and plug wires just to eliminate the chances it is that as well as put more new bits on this once neglected machine.

James, good to meet you this past Saturday at TWoS. Sorry to hear about your problem getting home. I hope the new coil and wire gets it straigtened out.

Have you checked the spark plug gaps? I might be getting fooled, but those gaps in your photos look rather large.

I would put money on coil, lead or cap tracking to earth.
Once you get this fixed you may need to check your throttle bodies are clean and change the oil as it will probably be contaminated with fuel.

cognosticator wrote:

James, good to meet you this past Saturday at TWoS.  Sorry to hear about your problem getting home.  I hope the new coil and wire gets it straigtened out.

Great meeting you too! I had a good time hanging out with you there...let me know the next time you roll up there!

Ok, had time to do some things to the bike today and run around on it a bit, including some highway time to really put some fuel through it.
I changed out the coil with a brand new unit. I replaced the out plug wire with a used spare I had.
I also replaced both outer plugs with the original spec ones, NGK BPR6ES. (Those are the ones that go outside, right?!) I have not checked the PMR8Bs that I have behind the frame.
The bike was fine for a bit (with a lot of burbling but not outright popping on deceleration) and still pulled fine...but on the way home the issues were very noticeable. A lot of hesitation and surging around the cruising area of 4k rpms and 5k rpms. No more burbling when off the throttle but it felt like it was missing any power if i wound the throttle far back...then more and more stumble..but idles just fine.
No codes are shown..and the only thing added was a new wire harness...and that was gone over pretty intensely before putting the bike back together.
I have not pulled the plugs yet (just got home) but I will later to see just how black they are.
Next steps?
Pull the injector on that side and examine?

I recently 'over cleaned' my inlet manifolds without removing the injectors, and deposited a big lump of crap across one nozzle...
remove the lead (careful with the metal spring clip, it will disappear into the garage somewhere) and allen screw and wriggle/pull the injector out -its kinda held in by an o-ring.
sometímes its the simple things....

Er...Pat, you know you only have to depress the spring clip on the injector?

I can swing over tomorrow and hook it up to the laptop! I wonder if it's something w/fuel pump or tank swap. I'll call in the morning.

it was already appeared quite sad I think Beetle, so I tickled it instead, hoping to release some tension and angst

GuzziSteve wrote:

I can swing over tomorrow and hook it up to the laptop! I wonder if it's something w/fuel pump or tank swap. I'll call in the morning.

Sounds good Steve, thanks!

This is that right side after about 15 - 20 miles on a new plug
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and this is the left
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I didn't pull the tank and check the inner plugs though.

Do you have a compression check gauge?

GuzziSteve wrote:

Do you have a compression check gauge?

I don't have one of those handy. If I went to get one, any suggestions?

Many of the parts stores will loan you one. Remove plugs, hold throttle wide open, both sides should be close to the same.

Well, I got a lot of good advice and I think I should update this thread with how things have gone.

The first thing I did was replace the coil and plug wires on the side giving an issue.
No improvement
Run some Seafoam in the tank.
No improvement
Next up, (on advice from Steve) swap the injectors to see if the issue moves with it to the other cylinder.
Oddly enough, both plugs looked great. That was confusing but I went with it.
My test drives to see if any fix has sorted it is to take 3 trips that gradually reach over 50 miles or more and check status of things between tests.
Things seemed good until the 3rd trip, my commute into Downtown Atlanta.
Service light came on,,,then went away and the bike stalled on a major highway. I was able to bump start it while I was going (in high gear) around 70 mph. Limped into the parking garage. Left it at work till the next day when I could bring some tools. Pulled the plugs...and they were looking fine.
So, now the issue is something else? Hmmm..fuel or spark...fuel or spark...
Well, time to eliminate Fuel as a possibility. The fuel pump was a gross mess of hoses that really were not fuel rated (GuzziSteve pointed that out) and not stock. The injectors looked fine..but I had no clue until I could send them off for testing.
I found a used and beautifully stock fuel pump on Ebay and ordered a set of those Chinese knock off injectors, so I can send off the stock units while I try these out.
Finished my 3 trip this morning and she passed with flying colors!
No stumble, no lurching and no stalling.
I still need to continue testing this out but I have more confidence in this bike now then I have had since I got it!

You can test the injectors yourself with GuzziDiag.

Just a caution on the knock-off injectors - your fuelling now "maybe" a bit richer. Keep an eye on it - perhaps they are not the same specs as the originals but fairly close. Manufacturing tolerances?

After more than a month with mine, I am fairly close to correct fuelling. The fuelling was way rich.

Good point! I will be getting the connection kit soon to use GuzziDiag...I am hoping the instructions make sense once I have all the stuff to do it with.