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

My bike developed a speed and hill climbing limiter today. I adjusted my chain before this weekends ride for the second time in years and the rear sprocket looked okish, mid-Oxley Hwy it started jumping teeth with a fist full. So I ambled in the last 80ks. This morning it was checked and the chain was slightly loose but the sproket was much worse. Heading home I bearly made Gloster with some big hills to climb. I don't have my usual 12-inch shifter so I had to buy one. Its a beauty and at $45 it should be. 8 inches long but with a max jaw opening of 50mm, it fitted the big inner rear wheel nut a treat. Made it home on this adjustment happily. That will be my last alloy rear sprocket when you go they go fast with limited warning.
 
Vince said:
My bike developed a speed and hill climbing limiter today. I adjusted my chain before this weekends ride for the second time in years and the rear sprocket looked okish, mid-Oxley Hwy it started jumping teeth with a fist full. So I ambled in the last 80ks. This morning it was checked and the chain was slightly loose but the sproket was much worse. Heading home I bearly made Gloster with some big hills to climb. I don't have my usual 12-inch shifter so I had to buy one. Its a beauty and at $45 it should be. 8 inches long but with a max jaw opening of 50mm, it fitted the big inner rear wheel nut a treat. Made it home on this adjustment happily. That will be my last alloy rear sprocket when you go they go fast with limited warning.
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You sure you haven?t got rats in the shed Vince..... that have taken a liking to ally ?
Can?t believe it would deteriorate that quickly  :-\
 
Must have been a very worn chain Vince. And a matching sprocket. As chains lengthen with wear the sprocket goes with it. Hard to believe it was ok when you left. Also hard to believe you?ve only had to adjust it twice in years!!!
 
Paul Marx said:
I was wondering about carb springs, now I have a lighter clutch with The DAM kit.

I seem to remember you can cut a bit off the original springs?

Paul
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When springs are shortened it actually increases the spring constant i.e. stiffer, but with less preload. it actually makes majority part of the throttle pull heavier.
Dellorto make three rates of carb srings: heavy, medium and light. https://damclassicracing.com.au/50120047-dellorto-spring-carb-slide-light/
The light weight Dellorto springs available that make a big difference in throttle pull. We have never had a slide stick in the wide open position using these springs (which is the scary thing that most people first think of when using a single pull throttle cable).
On  all our triples, racers, and the Land Speed Record Laverda 500 we used these light springs but also put a second extension spring along the frame of the 500 to make the pull even lighter lighter without compromising the spring force that pushes the slide down.
 
Greg Parish said:
When springs are shortened it actually increases the spring constant i.e. stiffer, but with less preload. it actually makes majority part of the throttle pull heavier.
Dellorto make three rates of carb srings: heavy, medium and light. https://damclassicracing.com.au/50120047-dellorto-spring-carb-slide-light/
The light weight Dellorto springs available that make a big difference in throttle pull. We have never had a slide stick in the wide open position using these springs (which is the scary thing that most people first think of when using a single pull throttle cable).
On  all our triples, racers, and the Land Speed Record Laverda 500 we used these light springs but also put a second extension spring along the frame of the 500 to make the pull even lighter lighter without compromising the spring force that pushes the slide down.
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That part is correct Greg.  But with the amount of preload of the stock springs, shortened springs (by about 25-30%) don't even come near that at WOT.  So, pull is lighter throughout the entire range.

I've been using shortened springs, with the cut coil modded to form a proper base, for decades.  I've never experienced a sticking throttle.  When swapping to Mikunis on my 3C, the stiff pull bothered me to the point that I removed one of the 2 return springs.  Again, no sticking throttle, not even under track conditions.

It does help to have decent throttle cables in good condition, properly routed and well-lubed. :D  The crap that I often remove from customer bikes is simply scary...

piet
 
TodayI had a good time with my RGS, visited my Mum at the other side of the German Sauerland, made 400 k in less than 5 hrs- wonderful RGS
Andre
 
Just wondering whether anyone has set up a fly-by-wire throttle using an Ignitech ignition. Those gadgets have a TPS input that can be mapped to a servo motor output. That would get around the problem of heavy throttle action.

I have in mind a mate's Guzzi race bike. It has a QA throttle that's ridiculously heavy. But it also has an Ignitech ignition so there's the possibility of a fly-by-wire conversion. Just need to source a twistgrip potentiometer TPS and a suitable servo motor to lift the carby slides.
 
Seat of the pants, or pain in the wrist, is that cut downs are lighter throughout. I agree fully with Piet, that new, good cables and bends throughout are a big part of the equation. I have had stiction with dells, on returning to idle which happened in rain weather, it disappeared when I swapped out K&N filters for foam Unifilter ones. Also had them sticking not wanting to open, coming out of corners etc, fixed with new cables. This was all on SF.
 
Dellortoman said:
Just wondering whether anyone has set up a fly-by-wire throttle using an Ignitech ignition. Those gadgets have a TPS input that can be mapped to a servo motor output. That would get around the problem of heavy throttle action.

I have in mind a mate's Guzzi race bike. It has a QA throttle that's ridiculously heavy. But it also has an Ignitech ignition so there's the possibility of a fly-by-wire conversion. Just need to source a twistgrip potentiometer TPS and a suitable servo motor to lift the carby slides.
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Didn't Cape do that?

On my Le mans which has the QA throttle I ended up swapping to sofet springs and Del tops from a Cali which gave a better cable run. Still bloody heavy compared to the Miks on the Laverda but.
 
And apparently got 70mpg and no downside on a Jota, wish I was smart enough to try it myself. Now, who around here could try it and see.
 
Davo said:
Didn't Cape do that?
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I think he used the TPS feature to support ignition mapping.

Ride-by-wire is a lot of tech gizmos and wiring for very little gain imo, especially if retro-fitted to a carbed bike.  Certainly OK as an engineering exercise to prove that it can be done... :D

piet
 
Yep Cape did a TPS, have one on the RGS with the FCR's .

fly by wire, auto manufacturers are still working that shit out and perfecting why would you bother ?
 
Brett said:
Yep Cape did a TPS, have one on the RGS with the FCR's .

fly by wire, auto manufacturers are still working that shit out and perfecting why would you bother ?
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Have you set that up yourself, Brett? If so, is it useful? And does it alter the advance curve and how difficult is it to do on FCRs?
 
Brett said:
fly by wire, auto manufacturers are still working that shit out and perfecting why would you bother ?
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I doubt that manufacturers are still working it out. The technology has been around for years.

Why you'd bother is because it can get uncomfortable using a heavy throttle on a bike, especially if you're opening and closing it a lot and using the full throttle travel, as you do in race conditions. Look at MotoGP bikes. They all have electronic throttle control. Fly-by-wire throttle is now common on a lot of modern road bikes, especially multi-cylinder bikes where you're opening a bunch of throttle bodies. An electronic throttle is pretty useful (although not absolutely necessary) for traction control programming too. Modern bikes need a TPS to feed data to the CPU for the fuel injection map. So why not also use the TPS to drive the throttle bodies open and closed?

Dunno about cars, but I guess throttle pressure isn't such an issue in a car because you need a little bit of throttle pressure to comfortably support your foot.
 
It?s one of the benefits of riding our old bikes for me, none of the fantastic can?t live without it electronic brain steered traction wheelie modes suspension. Most modern cars you see on tow trucks these days haven?t crashed, the data has. If someone is keen, go for it, could fit the Marelli motogp spec system.
 
Dellortoman said:
I doubt that manufacturers are still working it out. The technology has been around for years.

Why you'd bother is because it can get uncomfortable using a heavy throttle on a bike, especially if you're opening and closing it a lot and using the full throttle travel, as you do in race conditions. Look at MotoGP bikes. They all have electronic throttle control. Fly-by-wire throttle is now common on a lot of modern road bikes, especially multi-cylinder bikes where you're opening a bunch of throttle bodies. An electronic throttle is pretty useful (although not absolutely necessary) for traction control programming too. Modern bikes need a TPS to feed data to the CPU for the fuel injection map. So why not also use the TPS to drive the throttle bodies open and closed?


Have electronic throttle on my Triumph Explorer - it is very easy to hold but a massive benefit is the addition of cruise control which can provide the wrist with rest over a motorway section which are sometimes necessary and have speed restrictions
Dunno about cars, but I guess throttle pressure isn't such an issue in a car because you need a little bit of throttle pressure to comfortably support your foot.
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Went to a classic and vintage show in west wales on my mirage. Some lovely stuff there and swapped bikes for a ride on the way home with a friends? Ducati Multistrada, the Ducati has a lovely, comfortable riding position and is very fast but lumpy low down and in higher gears. After my brush with modern motorcycles I think I will stick with older stuff, for everything the Ducati could do I prefer my mirage, especially how useable the engine is when not doing higher speeds.
 
Tyrone said:
Went to a classic and vintage show in west wales on my mirage. Some lovely stuff there and swapped bikes for a ride on the way home with a friends? Ducati Multistrada, the Ducati has a lovely, comfortable riding position and is very fast but lumpy low down and in higher gears. After my brush with modern motorcycles I think I will stick with older stuff, for everything the Ducati could do I prefer my mirage, especially how useable the engine is when not doing higher speeds.
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I think that's the problem with engine mapping usually set very lean at low revs to conform with emissions regulations.

Paul
 
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