To Lambda or not to Lambda, that is the question.

[OneFootInTheGravy]

Unfortunately, the whole glovebox unit that houses the glovebox door is held in place not just by several screws mounted around the outside of the glovebox unit, but there is also a very large screw mounted centrally just inside the glovebox in a central position.

Yes, I had spotted that

As drastic as it sounds, as it is only the one screw I'm considering drilling a small hole in the glovebox door so that I can get to it with a screwdriver. I could then 3D print a small cover to temporarily pop in it. I have already bought some paint and filler as I need to fix some rust patches on the seam behind the front wheel so I could just filler and paint the hole in the glovebox at the same time.

[Data]

Before doing that just try to get something directly on that hooked latch. Push down & it'll open. The central screw talked about earlier is a very big cross head one. Personally, I wouldn't drill the door, tempting though it is. I'd have it open for you in a jiffy if we were closer with no damage. Dealer might pop it open easily too. Just depends on how knowledgeable their techs are.

[OneFootInTheGravy]

I'm IN!

I took it to my closest Vaspa dealer (I've had my Vespa over 4 years and I have never actually been to see them before) and they were in within 5 minutes!

It turns out that I wasn't actually doing anything wrong, a little metal clip and fallen into the latch and was stopping it from opening. They managed to get the door open by wedging some plastic in the bottom of the door, pushing it upwards helping it clear the catch when they pushed on the latch from the back, I can't believe I didn't think of that!





I can actually remember losing this back last year when I did a coolant change!

Anyway, back to the point at hand. I have now managed to have a look at the spark plug, and I'd say it's a bit on the pale side!?



I have put a new spark plug in and will run it for the next couple of weeks then take another look.

[OneFootInTheGravy]

Also, I was looking at the new facelift (RST22?) GTS Supersport while I was there. It looks really nice with all the black trim they have added. The only thing I wasn't so keen on was the chrome trim around all the switches on the handlebars, it looked a bit cheap to me compared to the rest of the bike. They had a green one and an orange one (I think that might have been the 125 though) and both looked really nice, I wouldn't know which one to choose

[roadster]

Anyway, back to the point at hand. I have now managed to have a look at the spark plug, and I'd say it's a bit on the pale side!?



I have put a new spark plug in and will run it for the next couple of weeks then take another look.

Was that irony? I would say your plug was a fairly healthy chocolate brown colour on the bit that matters but that type of plug has a non adjustable gap so as the electrodes gradually get eaten away you have no choice but to replace it. Incidentally the twin earth electrode design was never really shown to be advantageous because you only get one spark at any given time.

[OneFootInTheGravy]

Was that irony?

No, sorry. I'm not much of a mechanic (though I'm slowly learning), I was just trying to compare it to pictures on the interweb but it's kind of hard. For future reference, which bit is the 'bit that matters' then?

[Data]

I'm IN!

I took it to my closest Vaspa dealer (I've had my Vespa over 4 years and I have never actually been to see them before) and they were in within 5 minutes!

It turns out that I wasn't actually doing anything wrong, a little metal clip and fallen into the latch and was stopping it from opening. They managed to get the door open by wedging some plastic in the bottom of the door, pushing it upwards helping it clear the catch when they pushed on the latch from the back, I can't believe I didn't think of that!





I can actually remember losing this back last year when I did a coolant change!

Anyway, back to the point at hand. I have now managed to have a look at the spark plug, and I'd say it's a bit on the pale side!?



I have put a new spark plug in and will run it for the next couple of weeks then take another look.

Glad you got the door open. Actually the spark plug looks somewhat 'dark' on your photo. In 'real life' I appreciate it might look different. Generally when fitting an aftermarket exhaust such as the one you have, the motor will run either richer by some way or slightly lean. Yours looks a bit rich with its mixture.

Roadster regarding twin electrode plugs used in the Vespas, they do offer an advantage. The spark will alternate from electrode to electrode caused by changing electrode temperatures which in turn alters resistance. It thus reduces electrode/fuel shielding ensuring cleaner combustion & thus emissions & fuel economy. Indeed you can also adjust the electrode gaps by gently tapping each electrode until the correct gapping is reached. I've just done mine! But anyway, that's the reason many engines now use multiple electrode plugs. Some with as many as 4 or 6 electrodes. This causes a more radial spark effect as the revs rise. You can see this effect in many different videos on YouTube. So they do work.

[Data]

OneFoot, the proper way to do a plug reading test is to run the bike at or near full throttle over two or three miles. Then stop, let the bike cool, & then remove the plug. Check colour. If you don't run the motor at full throttle you won't get a proper reading as the lambda will interfere by doing its best the either lean or richen the mixture to that required by the engine. That's not a reading you want. What you really need is to check the full power plug reading as that is key to getting the motor to run with the proper mixture at all revs. Don't forget the lambda only operates up to 3/4 engine revs & then direct ECU fuelling takes over, ignoring lambda. This means mixture is set & won't change, just the amount/volume of fuel/air going into the motor. It's this mixture that is mostly affected by an exhaust change & needs to be right so you don't damage engine over a period of time.

[roadster]

Was that irony?

No, sorry. I'm not much of a mechanic (though I'm slowly learning), I was just trying to compare it to pictures on the interweb but it's kind of hard. For future reference, which bit is the 'bit that matters' then?

Its probably important to say that the exact colour is not necessarily very indicative except when you remove the plug immediately after a highish speed run. But its the nose of the insulator immediately next to the centre electrode that is a guide. Yours is on the dark side of brown but this could just be because the engine was recently operating at part throttle or not completely hot. If the engine were getting too hot, or if the spark plug itself was overheating, the tip would look ash white and there might even be signs of metallic deterioration of the electrodes. For many years Haynes manuals carried a picture, from Champion if I remember correctly, showing subtly different plug colours and conditions but technology has moved on and I doubt whether they have much relevance to our sophisticated single cylinder engines.

[OneFootInTheGravy]

Was that irony?

No, sorry. I'm not much of a mechanic (though I'm slowly learning), I was just trying to compare it to pictures on the interweb but it's kind of hard. For future reference, which bit is the 'bit that matters' then?

Its probably important to say that the exact colour is not necessarily very indicative except when you remove the plug immediately after a highish speed run. But its the nose of the insulator immediately next to the centre electrode that is a guide. Yours is on the dark side of brown but this could just be because the engine was recently operating at part throttle or not completely hot. If the engine were getting too hot, or if the spark plug itself was overheating, the tip would look ash white and there might even be signs of metallic deterioration of the electrodes. For many years Haynes manuals carried a picture, from Champion if I remember correctly, showing subtly different plug colours and conditions but technology has moved on and I doubt whether they have much relevance to our sophisticated single cylinder engines.

Thanks, I was looking at the wrong 'bit' then