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

7 Laverdas made it in glorious sunshine at the last of this years Blue Anchor Bay.




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Today I quickly checked Paul's favorite object of desire on the Eagle - the breaker contacts :).

It's that straightforward with a simple feeler gauge and a test lamp.
Checking the ignition timing is not optimal as standard. A wire bracket as a pointer is unstable, read off to the marking on the motor housing is imprecise. So that you can check the markings for the ignition timing more precisely on the starter freewheel, I built a simple auxiliary tool that fits all old 750s.

If the starter freewheel is fixed correctly and free of play on the crankshaft, this tool can be used to read the exact TDC.
With every engine, the tool is aligned exactly in the middle of the lateral (pic 2), central cast web on the cylinder.
I tested this on different engines with the dial gauge - the result is accurate.

By the way: Maybe this is due to the oil that I occasionally put on the lubricating felt for the breaker cam - the breaker distance has to be readjusted extremely rarely. The toothed V-belt runs much easier and is very durable - this may be an advantage for our racing drivers.

Thomas aus LAU

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Thomas aus LAU said:
Today I quickly checked Paul's favorite object of desire on the Eagle - the breaker contacts :).

It's that straightforward with a simple feeler gauge and a test lamp.
Checking the ignition timing is not optimal as standard. A wire bracket as a pointer is unstable, read off to the marking on the motor housing is imprecise. So that you can check the markings for the ignition timing more precisely on the starter freewheel, I built a simple auxiliary tool that fits all old 750s.

If the starter freewheel is fixed correctly and free of play on the crankshaft, this tool can be used to read the exact TDC.
With every engine, the tool is aligned exactly in the middle of the lateral (pic 2), central cast web on the cylinder.
I tested this on different engines with the dial gauge - the result is accurate.

By the way: Maybe this is due to the oil that I occasionally put on the lubricating felt for the breaker cam - the breaker distance has to be readjusted extremely rarely. The toothed V-belt runs much easier and is very durable - this may be an advantage for our racing drivers.

Thomas aus LAU

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If the starter freewheel has play on the crank, you needn't worry about the timing.
Why would racers need a dynamo belt?

Points aren't an object of desire, just a practical solution for people riding. As an aside, after 4 weeks touring on my SF2 this summer, the timing was more than 10° out on 1 cylinder due to points gap closing up.The bike was getting hard to start and would occasionally stall at idle. I'd put that down to altitude at first.
Paul
 
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Ah the blue anchor . Gee Shauan that was a great ride that day with you and Alan. Two 3c’s and my international Jota blasting through the beautiful countryside. Memories to die for😀👍
Tom
 
Paul Marx said:
If the starter freewheel has play on the crank, you needn't worry about the timing.
Why would racers need a dynamo belt?
Paul
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If the keyway of the starter freewheel on the crankshaft is not OK, the TDC marking is no longer correct. Due to the radius, 0.2 mm clearance/damage have a dramatic effect on the outside of the shaft = several degrees.

The large moving starter pinion on the crankshaft has of course nothing to do with the ignition timing.

With us, the vehicles for the racetrack are also driven on the road (with 07 license plates) - even long distances. This doesn't work for long without a V-belt and only with battery voltage. E.g. all three race bikes from "Pilot" are even driven hard on normal roads.

Thomas aus LAU
 
Thomas aus LAU said:
If the keyway of the starter freewheel on the crankshaft is not OK, the TDC marking is no longer correct. Due to the radius, 0.2 mm clearance/damage have a dramatic effect on the outside of the shaft = several degrees.

The large moving starter pinion on the crankshaft has of course nothing to do with the ignition timing.

With us, the vehicles for the racetrack are also driven on the road (with 07 license plates) - even long distances. This doesn't work for long without a V-belt and only with battery voltage. E.g. all three race bikes from "Pilot" are even driven hard on normal roads.

Thomas aus LAU
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TDC marking needs checking any how. Slop in the freewheel keyway if that's what you meant ,means crank overhaul, not TDC checking.

You're not talking about dedicated track bikes or riders then, so I understand about the belt.
Paul
 
Well I have no pictures but yesterday took my '79 Jota out for a blast did one of my favorite roads Skenes Creek Forest to the GOR bloody wet and quite mossy unfortunately one of my mates on his Hardly Davids bum lost it and ploughed up some mud, then later one of my other mates on his modern Enfield couldn't get the engine to start, the fault was a blown neutral light globe, so if the neutral light will not illuminate there is no starter motor (what a shit system), bit of a shame as the engine and gearbox on those bikes seem to be quite well made!!
So I took off on my second lap solo again with the taps well and truely open on my 42 year old Jota to empty a second tank of fuel.
Man wasn't that good for the soul!!!!!!
 
mauricejota7604 said:
Well I have no pictures but yesterday took my '79 Jota out for a blast did one of my favorite roads Skenes Creek Forest to the GOR bloody wet and quite mossy unfortunately one of my mates on his Hardly Davids bum lost it and ploughed up some mud, then later one of my other mates on his modern Enfield couldn't get the engine to start, the fault was a blown neutral light globe, so if the neutral light will not illuminate there is no starter motor (what a shit system), bit of a shame as the engine and gearbox on those bikes seem to be quite well made!!
So I took off on my second lap solo again with the taps well and truely open on my 42 year old Jota to empty a second tank of fuel.
Man wasn't that good for the soul!!!!!!
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Good as a tune up :D
 
While my sprag is in pieces waiting for parts, I gave the starter motor a once over. Cleaned out the carbon, polished the comm, yada yada. Reassembled and bolted it back on for a test. Nothing... hmmm what did I do wrong? Ahh, the battery has given up the ghost. 3.5 years out of a standard Yuasa, not bad I suppose.
Incidentally, the brushes aren't great, are replacements available? Otherwise I'll get some made up.
 
Andy said:
While my sprag is in pieces waiting for parts, I gave the starter motor a once over. Cleaned out the carbon, polished the comm, yada yada. Reassembled and bolted it back on for a test. Nothing... hmmm what did I do wrong? Ahh, the battery has given up the ghost. 3.5 years out of a standard Yuasa, not bad I suppose.
Incidentally, the brushes aren't great, are replacements available? Otherwise I'll get some made up.
Click to expand...
Replacement brushes are available from auto electric suppliers, otherwise easy enough to cut to size.

Paul
 
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