Spark Plugs, what do you guys think?

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Triton Thrasher said:
Then the side with the hot looking plug might appreciate a bigger main jet, if you are sure there’s plenty fuel flow from the tank.

Don’t raise the needle and change the jet. Test one change at a time.
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Yes plenty of flow, both peacocks open and give good flow and about 7L in the tank.

I am just wondering why that side runs so hot? Maybe am over thinking it but...
 
gortnipper said:
Yes plenty of flow, both peacocks open and give good flow and about 7L in the tank.

I am just wondering why that side runs so hot? Maybe am over thinking it but...
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Yep, probably just a little leaner than the other side.

Just because the carbs and jets are the same size, don't assume they are going to give you the same mixture.
Even a single carb seldom [never] gives the same mixture on both cylinders.
 
comnoz said:
Yep, probably just a little leaner than the other side.

Just because the carbs and jets are the same size, don't assume they are going to give you the same mixture.
Even a single carb seldom [never] gives the same mixture on both cylinders.
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When I first started out mechanic-ing, I would laugh when I found different jets/settings on carburetors in a multi-carbed engine, thinking what an idiot the previous owner/mechanic was to have not checked to ensure the same jets/etc were in each carb. Fortunately, an experienced mech took me under his wing and informed me (and demonstrated on a dyno) that it may well have been intentional to get the best performance from the engine. Of course, it's still possible that finding different jets/settings could be a mistake by the previous owner/mech...but maybe not!
 
All runs done on a private road as I would never go over the speed limit on public roads ;)

Recap: new barrels & 880 pistons + head worked on by Jim C. running on unleaded petrol.

Did a number of 'high speed' runs today.

Pushed the revs up to 5K which works out at 100mph indicated on the speedo.

Did a plug chop, just above 5K, throttle just above 3/4 turn, here's the plugs:

Spark Plugs, what do you guys think?


Spark Plugs, what do you guys think?


Seems OK to me, heat change point on strap seems, to my eyes, to be where it should be..

Full ring of carbon, 2-3 threads with colour.

Porcelane is white, which I believe is OK for unleaded.

I'll look a bit closer later today & see if I can see a ring of black at the base of the porcelain.

Bike pulling like a train, tickover like a clock, could have gone over the 100mph but rider was getting too much wind blast! I also noticed when I snapped the throttle at 5K I got clutch slip, which is fair enough!!

What do you guys think of the plugs?

Just had a look at the plugs again, I've all manner of magnification devices but can't really see the base of the porcelain or at least I don't seem to be seeing a ring of carbon around the base of the porcelain.

Did a compression test while the engine was still warm, throttle fully open, approx. 6-7 secs on starter, 190psi both left & right. I'll take that as an indication that the rings are bedded in!
 
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Nice one Click, looks like you’re sorted !

Just gotta beef your clutch up now eh?
 
Thanks lads, setup for the summer season :)

Starting to research all things clutch related!!!
 
cliffa said:
Sit down, pour a whisky and contemplate a job well done.

Sláinte
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Thanks :) but the praise really needs to go to Jim C. and everybody on this forum. I was just the grease monkey tightening nuts & bolts!
For the likes of me this forum is a fantastic resource & support, I've had lots of 'advice' in the past from 'experts' who I've met along the way & it's taken me many years to realise that most of it was hogwash & just information they had heard & just passed it on without any 'real' life experience.

Now, where did I put that bottle of whisky:rolleyes: Sláinte ;)
 
click said:
Thanks :) but the praise really needs to go to Jim C. and everybody on this forum. I was just the grease monkey tightening nuts & bolts!
For the likes of me this forum is a fantastic resource & support, I've had lots of 'advice' in the past from 'experts' who I've met along the way & it's taken me many years to realise that most of it was hogwash & just information they had heard & just passed it on without any 'real' life experience.

Now, where did I put that bottle of whisky:rolleyes: Sláinte ;)
Click to expand...
Well, obviously have one for Jim too :rolleyes:
 
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