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I've got all the parts collected to build an MB 6 plate clutch and it's high time I got around to putting it in! I tried out an external mic. How does my jetting sound? I think it sounds a little lean when I close the throttle after a fast run.

That bloke in the car park at the end of the vid came close to banging into you, probably distracted on his phone as they usually are

Yes, he did. I think the Tesla automatic brake kicked in. He was turning into a one way lane in the car park the wrong way. He was supposed to go straight, but he came right at me. He later apologised when I saw him at the store.

To my ears, it sounds as though your carburation is not spot on but that could be a product of your exhaust blowing or cracked. The exhaust sounds as though it's blowing @ the cylinder.

You seem to have a tendency to 'short shift' before getting to WOT so I suspect you are subconsciously trying to work around clutch slip.

The last engine build I did was my extensively ported TS 70 x 60 mm. I set up a six plate clutch using OEM (Innocenti) components with CamLam plates/frictions using ATF. No drag & no slip. It's not been on a dyno but the (very pleased) owner estimates comfortably in excess of 30 BHP....

Carburetion is very rich at 1/4 throttle. Yes, I have been working around that when I ride. I'm running a Mikuni TMX 35 that's been on this scooter since 2005. I have gone from 57 jet needle to 58, and if I run the 58 at its leanest position, the engine runs really well but then way too lean at 3/4 throttle. It was set like this when I holed the piston back in July. Currently the rest of the jetting is: 370 main, 22.5 pilot jet. Do you think it's possible that the carburetor has worn over time? It's done a lot of miles an there is visible wear of the slide.

I'll look at the exhaust more closely tomorrow. It's a Franspeed Race, pretty rusty and there's a dent on the down pipe where it contacted a wheel well when we took our scooters to the USA Lambretta Jamboree in July.

I had a look today and there is blowback from the exhaust I think where it slips into the exhaust manifold. It's a Franspeed Race. What can I use to seal it? I tried "exhaust sealant" and that seemed to only work for a short while. The exhaust may be bent. There's a dent in the downpipe where the scooter rested on the trailer that took it up to the Lambretta Jamboree in Northern California. I've just ordered a new Franspeed Race (Bolt-on) from JL Exhausts. And I'm buying a new Mikuni TMX 35 direct from Sudco next week.

Also Russ Shea helped me and pointed out what I had done wrong when I built my clutch. The top plate is protruding and the ears aren't catching on the spider. I hadn't done any measurements before building. So I'm going to try again.

GP Kevo wrote: Do you think it's possible that the carburetor has worn over time? It's done a lot of miles an there is visible wear of the slide.

Hiya Kev, hope you're doing well. We met at a petrol station, a few years ago on one of the Euros albeit briefly.
The problem with the Mikunis is the wear on the atomiser and needle . See link below. I was having all sorts of problems with one of my TS1 engines and bought a brand new Mikuni and this changed the behaviour of the engine for the better. I was told at the time if you're on a 58 then you need to be buying new.

viewtopic.php?f=6&t=6567

Good Luck

nickw wrote:

GP Kevo wrote: Do you think it's possible that the carburetor has worn over time? It's done a lot of miles an there is visible wear of the slide.

Hiya Kev, hope you're doing well. We met at a petrol station, a few years ago on one of the Euros albeit briefly.
The problem with the Mikunis is the wear on the atomiser and needle . See link below. I was having all sorts of problems with one of my TS1 engines and bought a brand new Mikuni and this changed the behaviour of the engine for the better. I was told at the time if you're on a 58 then you need to be buying new.

viewtopic.php?f=6&t=6567

Good Luck

Hiya Nick, we probably met in Austria in 2015
Yeah, I had heard about carb wear, too and the guys at Sudco confirmed it. I bought a new Mikuni TMX35 from them and will be putting that in sometime this weekend.
It's not as exciting here in Los Angeles. There are a lot of Lambretta owners in California but no regular event large enough to attract everyone to ride to it. Some of us are trying to change that, though. I miss the buzz of riding to a Euro Lambretta event and back.

Broady does a EN59 Mikuni needle now