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

piranha-bro2 said:
Never seen a twin running on 10s. But if they're working, no big deal. Definitely agree with Lee about isolating your circuit for coils. I also run a relay, so the ignition switch simply connects a heavy power supply wire to my fuse box and then direct wiring to various components. Earthing is also important - often disregarded. Give everything as much juice as you can.
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You mean like this, Quentin?

Unashamedly stolen from Grants FB page, I do hope he can forgive me!

piet

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Even drawing constant milliamps will drain the battery over time. A tenth of an amp draw is one amp after ten hours, and they add up on a bike not frequently in use. Run the Zumo on switched power unless it says that it needs constant power, in which case get a maintenance charger.
 
Removed the original battery tray with the huge 34Ah battery. New tray with 18Ah battery of a 750 test fitted. I took out all the electrical mess from the frame. Good question who made the wiring harness. Literally every wire was loped around the frame so it required some cutting to only get it out of the center of the frame.

Now is a good moment to find out where to install everything. The bike will be updated with a full Motogadget wiring harness.

Fuel tank fits nicely, maybe a bit high on the back but I have to admit the in the front is sitting very low. To fit the seat I need to cut hinges and lock from the original seat. So not everything is in the exact right and straight position. I’ll do my best😄

Herman
 

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Doing a bit of work on my bike shed, it's an ex-building site shed with a small 800mm wide door that didnt allow my bike to get through with its new panniers fitted. What I have been doing is mounting the panniers in the back lane, coming and going. So that takes a good 45 minutes to do, not so much fun at 6am in the dark with winter's short days or all the prying eyes of possible bike borrowers. So by cutting the door down the middle and bolting it to a 1220mm sheet of Marine Ply, that's the fix. I knew it wouldn't be easy, but I hadn't noticed the Door was made out of 2mm steel, really not fun. Luckily, a demo blade in a Sabre Saw managed, my back, not so much. So 3 Days ago I was cutting a 10 Gauge Gal Tech head out and it caught on the grinder and disappeared into the grass right where the bikes leave. FUCK, I expect it will end up in a tyre. Just found it by pure luck. Talk about a can of worms. Happily, nearly finished.
 
piranha-bro2 said:
Never seen a twin running on 10s. But if they're working, no big deal. Definitely agree with Lee about isolating your circuit for coils. I also run a relay, so the ignition switch simply connects a heavy power supply wire to my fuse box and then direct wiring to various components. Earthing is also important - often disregarded. Give everything as much juice as you can.
Click to expand...
Visited my father a few days ago, long story to the bike of course, but the somewhat condensed one is that as this engine is a much later number than the original, it was swapped with the worn-out original. (back then a lot cheaper to buy a running Laverda than rebuilding an engine). Turned out however it had been opened before and the head had so much taken off (either by necessity or shoddy work, it was like that when my father put in the bike) which my father did not know. Gave it a full service then after a few weeks had holed pistons... It still had the sidecar back then.
Only then it appeared the head had so much taken off, after fixing it all up and consulting Gijs van Dijk he then special-orderd the 10s for this compression + side car & that has been like it ever since. It also has dual foot cilinder gaskets. My father agreed w/o the sidecar it would probably run well on 8 or 9s now. I wonder how old those plugs are -the sidecar has been sold ages ago!

My father+bike were featured in Moto'73 magazine a few years ago, they did a technical check and it turned out, after a lot of kilometers, the compression ratio was still 9:1. After a quick internet search, that appears to be more like my R90S, and an SF, than a GT.

Caveat is this is mostly parroting my dad though, as I was a little guy back then & work in healthcare IT, not a bike shop :D Glad I can still ask him about it, brings up some nice memories for the both of us too.

for my own comprehension: I assume the compression ratio gets higher, because the head had so much taken off, it makes the combustion chamber smaller? Probably a lot more to it (shapes of head, pistons and what not?) though.
 
jko_78 said:
Only then it appeared the head had so much taken off, after fixing it all up and consulting Gijs van Dijk he then special-orderd the 10s for this compression + side car & that has been like it ever since. It also has dual foot cilinder gaskets. My father agreed w/o the sidecar it would probably run well on 8 or 9s now. I wonder how old those plugs are -the sidecar has been sold ages ago!

Caveat is this is mostly parroting my dad though, as I was a little guy back then & work in healthcare IT, not a bike shop :D Glad I can still ask him about it, brings up some nice memories for the both of us too.

for my own comprehension: I assume the compression ratio gets higher, because the head had so much taken off, it makes the combustion chamber smaller? Probably a lot more to it (shapes of head, pistons and what not?) though.
Click to expand...
Shaving the head or fitting a smaller base gasket will raise the compression (yes, by reducing the combustion chamber volume) but won't alter the shape. I shaved 1mm from my SF head and ran a 0.15mm base gasket to get 10:25 CR - I'd buretted the chamber and it only had an actual CR of about 8.5:1. Simple way to reduce CR is to fit thicker or two base gaskets. Raising CR and not rejetting raises the risk of holed pistons. I wouldn't have thought 10s in plugs was necessary, but whatever works. I still wouldn't run 8s in an SF unless it was going to be dawdled.
 
jko_78 said:
Visited my father a few days ago, long story to the bike of course, but the somewhat condensed one is that as this engine is a much later number than the original, it was swapped with the worn-out original. (back then a lot cheaper to buy a running Laverda than rebuilding an engine). Turned out however it had been opened before and the head had so much taken off (either by necessity or shoddy work, it was like that when my father put in the bike) which my father did not know. Gave it a full service then after a few weeks had holed pistons... It still had the sidecar back then.
Only then it appeared the head had so much taken off, after fixing it all up and consulting Gijs van Dijk he then special-orderd the 10s for this compression + side car & that has been like it ever since. It also has dual foot cilinder gaskets. My father agreed w/o the sidecar it would probably run well on 8 or 9s now. I wonder how old those plugs are -the sidecar has been sold ages ago!

My father+bike were featured in Moto'73 magazine a few years ago, they did a technical check and it turned out, after a lot of kilometers, the compression ratio was still 9:1. After a quick internet search, that appears to be more like my R90S, and an SF, than a GT.

Caveat is this is mostly parroting my dad though, as I was a little guy back then & work in healthcare IT, not a bike shop :D Glad I can still ask him about it, brings up some nice memories for the both of us too.

for my own comprehension: I assume the compression ratio gets higher, because the head had so much taken off, it makes the combustion chamber smaller? Probably a lot more to it (shapes of head, pistons and what not?) though.
Click to expand...
There are many factors to count in when shaving heads or otherwise modifying the top end of an SF. You will have to be very careful if and when you freshen it up. Shaving the head more than a small amount can bring the top lip of the cylinder sleeves in contact with the head surface, which can cause gasket problems. It can also bring the squish band, the flat part around the outside of the piston crown with the corresponding flat in the combustion chamber, under the vital 1mm minimum clearance needed on these motors. It also brings the valves closer to the piston, sometimes causing contact, depending on cam type or timing. Adding more base gasket material helps in some ways but is not the ideal solution. Then the motor needs carburation, ignition timing and advance that suits. There are many things to be measured and checked, it can't just be thrown together with bought parts (your dad had advice from Gijs), but hopefully you will never need to go there. As it is going great and does not appear to have any problems, just enjoy it.
 
Years back, I added gators and liked the idea of protecting fork seals, BUT you lose the ability to add a cable tie to get measurable fork travel used. Yes, you might wiggle the gatter up, but you will move that cable tie doing that.
 
Vince said:
Years back, I added gators and liked the idea of protecting fork seals, BUT you lose the ability to add a cable tie to get measurable fork travel used. Yes, you might wiggle the gatter up, but you will move that cable tie doing that.
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Set your sag once, Vince - get it right, then fit the gaitors ... job done.
 
I once saw an SFC750 which had had flat top Mondial low comp pistons fitted to it, for a bit more tractability and ease of usage, it was an elletronnica and the inlet valves hit the pistons.

I did at one time run TOG with 2 base gaskets for low comp, (flat top Mondials) no fuel woirries and ease of use, which worked very well, it was not the fastest (top end) triple by any means but it could certainly get up and go at lower RPM's. on a 1200 there is no raised up spigot on the liners, so head clash does not apply, TOG's head had been shaved at least twice (cant remember the thickness) but even then the timing chain would only just go on, any tighter and it would have been a no go state. shaving the head makes the chain loose, 2 gaskets makes it VERY tight and would not work on an unshaved head.
CLEM
 
Vince said:
Years back, I added gators and liked the idea of protecting fork seals, BUT you lose the ability to add a cable tie to get measurable fork travel used. Yes, you might wiggle the gatter up, but you will move that cable tie doing that.
Click to expand...
I don't do that.
If the fork doesn't go clunk on bumps or rattle my fillings out, then it's okay.
Paul
 
CLEMTOG said:
I once saw an SFC750 which had had flat top Mondial low comp pistons fitted to it, for a bit more tractability and ease of usage, it was an elletronnica and the inlet valves hit the pistons.
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Suppose they had used 1200 Mondials, in which case the pockets were not suitable for the elettronica’s bigger valves and different valve angle.

Marnix
 
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