Out and About on your Laverda.No bull,Just photos

"I can perhaps understand why. Although it makes the bike wider I've always preferred the Spondon, and the swing arm pivoting in line with the gearbox sprocket, over the Harris frames et al."

I have to strongly disagree with that Manxmog, the chain line of the bike and the swing arm pivot is a critical element in the bikes handling, almost any bike you look at will have the top run of the chain kissing the swingarm when parked, lots have a plastic/rubber slipper to safeguard that swing arm, especially dirt bikes, look at the way a 630 or to a lesser extent 530 will notch the swing arm on a Lav twin or triple, this is because under hard acceleration the taught top line of the chain will tend to load the front suspension and prevent lift, the reare squat is also then controlled. Many "specials" ignore this to some degree, e.g. Gary Laurence (Jota/Norton featherbed) where not only is the chain about 50 mm clear of the top of the swing arm, but he also runs 19/47 gearing (on 18" rims), so it goes like shit of a shovel, but tops out early and must be wheelie prone (which he admits to and rates it as super performance not bad hadling/under gearing) The famous Mike Hailwood 500 Honda 4 (the Camel) didnt handle at all well in any frame (I witnessed 3 variants) because everything was correct, except the crankshaft rotated backwards to normal, that meant the rear wheel was constantly losing trcation, it made for great spectating as SMBH wrestled it without fear. when buidling a special the cranksahft centre height is also critical and again very often ignored or impossible to comply with if you dont do major frame surgery, as in NorVin. our Rotax engined Zane has precisely the correct crankshaft centre height and forward/rear positioning, plus the engine is tilted slightly to get the sprocket postion good as well, so Spondon with swing arm pivot concentric with the gearbox sprocket = CRAP. if you want constant chain tension AND correct sprocket height, take a look at Nessie, currently on sale in Italy for around £40,00, I would buy it for £15,000.
CLEM
 
A shallow swingarm downslope angle will promote squat, a steep one will lift the rear steepening the rake slightly and reducing trail. The reduced trail gives reduced front grip, but the lifting rear counteracts this by pushing the front tire into the track. If all is correct geometrically, you have the advantage of increased rear traction and reduced rake for quicker steering with no loss of front grip.
 
CLEMTOG said:
"I can perhaps understand why. Although it makes the bike wider I've always preferred the Spondon, and the swing arm pivoting in line with the gearbox sprocket, over the Harris frames et al."

I have to strongly disagree with that Manxmog, the chain line of the bike and the swing arm pivot is a critical element in the bikes handling, almost any bike you look at will have the top run of the chain kissing the swingarm when parked, lots have a plastic/rubber slipper to safeguard that swing arm, especially dirt bikes, look at the way a 630 or to a lesser extent 530 will notch the swing arm on a Lav twin or triple, this is because under hard acceleration the taught top line of the chain will tend to load the front suspension and prevent lift, the reare squat is also then controlled. Many "specials" ignore this to some degree, e.g. Gary Laurence (Jota/Norton featherbed) where not only is the chain about 50 mm clear of the top of the swing arm, but he also runs 19/47 gearing (on 18" rims), so it goes like shit of a shovel, but tops out early and must be wheelie prone (which he admits to and rates it as super performance not bad hadling/under gearing) The famous Mike Hailwood 500 Honda 4 (the Camel) didnt handle at all well in any frame (I witnessed 3 variants) because everything was correct, except the crankshaft rotated backwards to normal, that meant the rear wheel was constantly losing trcation, it made for great spectating as SMBH wrestled it without fear. when buidling a special the cranksahft centre height is also critical and again very often ignored or impossible to comply with if you dont do major frame surgery, as in NorVin. our Rotax engined Zane has precisely the correct crankshaft centre height and forward/rear positioning, plus the engine is tilted slightly to get the sprocket postion good as well, so Spondon with swing arm pivot concentric with the gearbox sprocket = CRAP. if you want constant chain tension AND correct sprocket height, take a look at Nessie, currently on sale in Italy for around £40,00, I would buy it for £15,000.
CLEM
Click to expand...
Okay Mr know-it-all. 😘
 
Alzero said:
A shallow swingarm downslope angle will promote squat, a steep one will lift the rear steepening the rake slightly and reducing trail. The reduced trail gives reduced front grip, but the lifting rear counteracts this by pushing the front tire into the track. If all is correct geometrically, you have the advantage of increased rear traction and reduced rake for quicker steering with no loss of front grip.
Click to expand...
Not quite sure I get it, Alzero??? Unless you mean under braking? I can't think of any conventionally - swingarmed bike doing anything other than squatting under power.
 
I mean under acceleration. With the appropriate angle and low speed compression damping on the rear shock the rear tire will try to run forward under the bike holding or hopefully increasing the downslope ever so slightly. You will never see this on a street bike, but look at photos of Superbikes and MotoGP bikes before active suspension and ride height control. They had steeper swingarm angles than any street bike. Some of that was to increase rake on production based machines, but it also helped with drive out of corners.
 
Not my Atlas, or Yogis. The only other one I have heard about was in South Oz, and it's not been seen for a very long time. So now there are 4 in Oz, Mmm.
 
Dear Mr Southern Pres, what's the Atlas story, Vic club member? Had it long, where did it come from? Not Geolfs bike from South Oz?
 
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