What did you do to or for or with your Laverda today?

That looks like the cupboard I added caster wheels to and chopped about for Martys shed, we bought a massive alloy plank to wheel the bike up as well. That's bloody funny.
 
chrisk said:
Me too, I'm like the old bull.

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My dad had a farm, mixed arable, dairy and beef.
Once, when I was about eight, I was leading our Aberdeen Angus bull, one ton of muscle and bone, down to the bottom pasture to work.
On the way, I passed some tourists walking on the road. They asked "Where are you going with that huge animal, Sonny, and why?"
"Taking him down to the bottom pasture to service the cows."
"Can't your father do that?"
"No, it's got to be a bull."
 
Started up my 3C which hasn't run since June. It's done all of 66 km since I finished restoring it. It started up easily despite 8 months old fuel and when warm, with a bit of fiddling of the idle screw, settled down to a nice stable idle around 1000 revs.
It seemed to be running very rich when I ran it last, but since then, I've come down to 125 mains from 130 and balanced the carbs.

I'm itching to get it out, if only the rain would stop.

Paul
 
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Paul Marx said:
I've come down to 125 mains from 130 and balanced the carbs.
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Might still be a bit rich. Only way to be sure is to put it on a dyno.

When I got my Jota it was way over-jetted. I think it had 140s or maybe 145s in it. Memory is a bit hazy on the exact number, but apparently the previous owner must have thought bigger jets would make it go better. After a few dyno pulls we came down to 120 mains and it was still a wee bit on the rich side. Factory jetting was 118 but we didn't have any of those available and 115 was too lean. Since then I've swapped to Mikunis. Doesn't go any better but isn't as thirsty.

Funny thing - when the dyno bloke saw how rich it was on the first run with the 140+ mains, he said it may as well not have main jets at all. So just for fun we gave it a run without any mains and he was dead right. It ran the same mixture at WOT as it did with the 140. The needle valve was doing all the fuel metering. It didn't start to lean out until we got down to about 130.

There's a lesson there. If you have 32mm Dellortos with (Laverda factory original) AB265 needle jet + K1 needle, don't bother going any bigger than 130 mains. If you think it needs bigger mains, save your money and run it without main jets.
 
Lee and I discovered that same thing with his SFC'd SF2 when we dyno'd it in Perth - K2 needle limited mains to probably 160 - we fitted K4s from memory and were able to set the main jet correctly.
 
Dellortoman said:
Might still be a bit rich. Only way to be sure is to put it on a dyno.

When I got my Jota it was way over-jetted. I think it had 140s or maybe 145s in it. Memory is a bit hazy on the exact number, but apparently the previous owner must have thought bigger jets would make it go better. After a few dyno pulls we came down to 120 mains and it was still a wee bit on the rich side. Factory jetting was 118 but we didn't have any of those available and 115 was too lean. Since then I've swapped to Mikunis. Doesn't go any better but isn't as thirsty.

Funny thing - when the dyno bloke saw how rich it was on the first run with the 140+ mains, he said it may as well not have main jets at all. So just for fun we gave it a run without any mains and he was dead right. It ran the same mixture at WOT as it did with the 140. The needle valve was doing all the fuel metering. It didn't start to lean out until we got down to about 130.

There's a lesson there. If you have 32mm Dellortos with (Laverda factory original) AB265 needle jet + K1 needle, don't bother going any bigger than 130 mains. If you think it needs bigger mains, save your money and run it without main jets.
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This one has 78mm pistons, so might need a bit more. Time for some dynamic testing.
Keith Nairn gave between 125 and 130 as the plausible range.
Paul
 
Don’t cry Scrumpy, it’s not as though it’s the last 750 you will own. And as it now has a new owner, who will hopefully ride it, you have done a good deed.
In fact the non-running 668 Diamanté I acquired a couple of years ago is now well on its way to recovery, I even had it running on the bench for a short while today, and should be available for someone to use very shortly.
 
Dropped in on Merlin today. He has done a nice job on my old Sprint.
 

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