Spark plugs reading

[sky02]

I have checked my spark plugs today and I don’t like the colour on my plugs especially on the rear one.

Front:

Rear:


I run regular unleaded, non ethanol EU 95. I think that the rear is to ashy grey?? Especially on the side electrode. Plugs are Denso x24epr-u9. They were taken out in a garage after a ride with different speeds and there were installed in the spring.

[Herb]

Looking at those, it appears that you are running way too rich, even with non ethanol. At most, they should be a light gray to tan color.

[sky02]

Here is rear in colder, brighter a bit unnatural light. It looks way brighter in that light but it shows that it is dry. I dont like that there is no tan/brown colour.



I have moved this summer from city to village in the foot of the mountains. The altitude difference probably makes the air thiner.
Do you think the idle circuit or needle? I pretty sure that I have tweaked the idle mixture. Needles are at the same setting i have tuned them in my previous location. Front raised one notch, rear half a notch.
She idles pretty good, pulls excellent around 3000-4000 rpms, 80-100km/h in 3rd gear (45-65mph), but bellow 30mph in 3rd gear feels a bit boggy (about 1750 rpm) and sounds like a agro tractor.

[sgtcall]

Also the Intruders run best on 87 octane gas, this is according to the owners manual. . Don't waste your money on the good stuff.

[sky02]

We don’t have that in Europe. 95 is the cheapest 98 is premium. But the calculation method is different our 95 is yours 87-91.

[Herb]

The rear plug, in that light, looks exactly like the one that comes out of my bike. It runs great, has great power, gets 45-50 mpg and never pings.

I run ethanol 87 (US) octane. When I can get it, the bike runs even better on 85 octane (again US).

Try a high gear roll on at about 55 - 60 KPH and see if it pings. If not you are just fine.

[sky02]

Colors are better on the first pictures. In the second post light is way brighter and colder. If by high gear roll you mean 4th speed (that’s my top) full throttle on even road. At 55-60 km/h she will accelerate poorly (compered to higher rpms) with that rhythmic tractor like sound but that’s 1750-2000 RPMs. Bike will sound and pull better closer to 80-90 km/h and feel most powerfull after 100 km/h. But that’s where the max torque is according to specs (3200 rpms).
You could cruise on 4th gear at 55-60 km/h thou with small throttle. No fun but quiet.

I'm not sure if I have a engine ping as i run without a windshield and its a bit noisy and lots of things rattle on that bike


A think that we had something like 91 octane but it was 30 years ago or so. And it was like 85-87 US.

I get about 100miles before reserve. But I do like hard acceleration i belive its about 45 mpg

[sky02]

Update:
I have some free time today and the weather is nice and shiny so Ive started some tuning. After som warmup ride I have installed the digital tachometer. Idle mix was a bit to rich on rear cylinder as after 1/4 of turn in idle rised 10-20 rpms and it was at hughest point, front was pretty spot on.
I took her on some open road. Installed fresh spark plugs and kept her for few miles around 3000rpms so between 80-100. Km/h on 3-4 gear.
Here are the plugs after turning off the ignition while at that rpms:
Front:

Rear:


I think the ride was to short and i will check them later today after a longer ride in the same way. But for sure she is not runing way to rich.

Update after 20miles:

Front:


Rear:


Some engine braking pop from left side (rear) while changing gear. I have added 1/16 turn on front as the threads looked a bit fresh.

[Herb]

Looks spot on to me.