Plug chop colours

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alanscottj
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Image

Uphill three quarters of a throttle

Image

On a straight half a throttle

Image

On a straight with full throttle




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alanscottj
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Following a bit of advice from you good fella's on here this is what i have ended up with (TS1-230, tuned/TMX35/Fran Race/Varitronic):

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Main jet 340
Pilot 25
Needle 56 2nd clip from top


And as you can see in the pictures the plug don't look too bad. My only gripe really is up to 1/8 - 1/4 throttle there is a bit of four stroking, am I right in thinking that this could be rectified by air mixture screw?
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holty
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i would say looking at all 3 pics it looks weak, last year when i holed a piston the plug was darker than that, may just be worth a dyno session to be sure, cheaper than a rebuild.
alanscottj
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holty wrote:i would say looking at all 3 pics it looks weak, last year when i holed a piston the plug was darker than that, may just be worth a dyno session to be sure, cheaper than a rebuild.
Will definitely still be doing a dyno Holty, I just want it to run safe until then. Can't get to dyne until at least the end of the month. Will try richening needle clip position and see how she goes :geek:
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Chris in Margate
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To me that looks a tad lean. Maybe raise the needle and try.
alanscottj
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Needle raised one clip, darker but not nice to ride, splutters like Image Image



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Scooterdude
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I'd say the first 3 pictures are not far off but it looks like your plug is to hot, try a colder plug on the original settings and see what it looks like then. Also I can't see on your pictures but we're the centre electrode and insulator meet are there any black or silver speckles? And are there any at the bottom of the insulator?
alanscottj
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Scooterdude wrote:I'd say the first 3 pictures are not far off but it looks like your plug is to hot, try a colder plug on the original settings and see what it looks like then. Also I can't see on your pictures but we're the centre electrode and insulator meet are there any black or silver speckles? And are there any at the bottom of the insulator?
I think the light in the first three pictures makes them look a lot lighter than they really are. As for the plug it is an NGK BR8ES and there looks to be a touch of white/silver on the very edge of the tip of the electrode, but only a very tiny amount :?:
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Scooterdude
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Ok those silver speckles would indicate a degree of pre-ignition which would suggest you really need to retard your ignition timing, but as your on a varitronic I really don't know how you would do that.
Try a BR9ES and see how it looks, although I don't think they have a great reputation for longevity, I guess you could try a Champion equivalent to the 9.
Ryskie
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First three look okay but If it were mine I'd aim for a bit darker. As above try an NGK 9 or a Denso W27ESU
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