Different Looking Plugs
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Last time I checked the intake seals with starting fluid it was good. A few years back I had to tighten it up, and the seals didnt look so good, so I will check those out again.. this did happen right after filling up (premium always) and a fuel truck pulled in as I was pulling out, so I could have gotten some crud from the bottom of the station tanks... I dont have VOES with the Mikuni carb.. Something else I should have mentioned and should also adress is I do get some popping on decel, like if I am all the way off the throttle and going down a hill. .. As far as oil consumption, by the time its down enoughto add even half a quart, its due for, and gets new oil. I do however leak from the rear base gasket a little.. I will post with my findings.. Thanks for the input.
Cruiser
Joined: Nov 2006
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Funny thing is, after getting home and on the PC, your pics are not nearly as large as they were on my phone with my original post followup to the pics. In my phone, I will reiterate what I said earlier. I believe the plug on the rear is overheated. Additionally, when you blow the pic up you can see that the front plug, although it looks "wet", has the same deposits (at least it SEEMS to) as the rear plug, but underneath the wet oil deposit. What I'm saying, and again you mention Popping on decel, is that the plugs look overheated. What were the conditions on the day this happened... i/e temps, type of riding, etc.. Have you done any mods to the bike that would change the fuel/air ratio? Please post those pics of the new plugs when you can.
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From: Near Frankenmuth, MI
Front plugs shows oil and carbon, bad rings or valve seats. Rear plug is the perfect shade.
You could possibly be looking at a failing lifter too.
Intake seal would give you carboned plugs, most likely both would appear identical but would not cut out and back on.
Sticky lifter is my best guess.
You could possibly be looking at a failing lifter too.
Intake seal would give you carboned plugs, most likely both would appear identical but would not cut out and back on.
Sticky lifter is my best guess.
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while i had it apart, i found one of the throttle cables to be very frayed, so, wait for new cables ... wait, wait, wait... but i i did go ahead and put the intake and carb all back together, and i can already tell the difference just by how it idles, great improvement.. at least im goin in the right direction, and i found that frayed cable in the garage and not on the other side of the pass!
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with new intake seals, i have smoother, quicker acceleration, and no popping on decel.. Odd thing happened on my way home from work yesterday.. it started to run like it did before i started... pulled over, checked my plugs, they looked fine, i think, let her cool, rode home like a champ. Temp on the dipstick was about 180, nothing odd, but i gotta wonder if i was just over heating? it was like 09 or so outside, but i havn't had it miss and be so tired like that before on this ride..
eitherway, back to the plugs, now that i have a few hundred miles, here they are
eitherway, back to the plugs, now that i have a few hundred miles, here they are
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From: Near Frankenmuth, MI
A little odd.
The cleanest one has greasy looking threads top to bottom like it wasn't tightened down correctly and exhaust coated the threads. Is the threaded area oily? Also it's "reading" that there is a lean condition in that chamber.
The other plug looks just right for normal use.
Were these put in fresh after you fixed the seals on the intake?
Here's a chart on plugs. It's bigger and you can zoom in on this link
The cleanest one has greasy looking threads top to bottom like it wasn't tightened down correctly and exhaust coated the threads. Is the threaded area oily? Also it's "reading" that there is a lean condition in that chamber.
The other plug looks just right for normal use.
Were these put in fresh after you fixed the seals on the intake?
Here's a chart on plugs. It's bigger and you can zoom in on this link
Last edited by JohnnyC; Sep 16, 2012 at 07:25 AM.
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From: SoCal hi desert
I have a very similar situation. My plugs don't match just like your first pic. had the same momentary cutting out thing too like it was dropping a cylinder. I have somewhat low compression in the rear though so that needs to be dealt with someday.
That said it when it happened the last time I bought a new coil and added a fuel filter from the tank. So far so good. The inside of my tank is pretty screwed up from what I can see so it may have been letting some crap hit the carb. There was a small amount of black stuff in the float bowl. Haven't had it off since I added the filter and new main jet.
That said it when it happened the last time I bought a new coil and added a fuel filter from the tank. So far so good. The inside of my tank is pretty screwed up from what I can see so it may have been letting some crap hit the carb. There was a small amount of black stuff in the float bowl. Haven't had it off since I added the filter and new main jet.
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Road Master
Joined: Apr 2009
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From: NJ
Did you recheck the intake seals affter you installed them, they don;t always seat well and people often assume they are good just because they are new.
The white plug looks ok except for the threads, not sure whats up with that unless it was loose, saw that on my truck once. The other one does not look all that good and they are obviously not close to being identical.
Check the seals, check the voes vacume line, and replace the donut where the carb fits if you have not already.
Ds
The white plug looks ok except for the threads, not sure whats up with that unless it was loose, saw that on my truck once. The other one does not look all that good and they are obviously not close to being identical.
Check the seals, check the voes vacume line, and replace the donut where the carb fits if you have not already.
Ds
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i didn't change the card to intake seal - BTW, i don't have the idle cable on anymore, not that it does anything with the Mikuni. - changed the oil and filter yesterday morning, just in case i cooked the oil friday... Rode today, ran great - I think i need to change out my spark cables, they take a hard kink up against the tank, and that cant be good