lost first gear

hi, Tippie, I've removed the neutral switch but to no avail just seen a mate today and he has one of those endoscope things that he said I can borrow so I will pick it up this week and will let you all know what I see, let's hope it's some in there that i can get out 🤞🤞
 
Looking grim acelav, well sort of, like a true Laverda rider, you will be a mechanic of much worth and skill in time. Not that the Laverda is a problem bike, basic engineering with road use outcomes. Am out of ideas here for external diagnosis.... better purchase another Laverda to ride around on, while the other is in for repairs, since your about to invest time and effort in advanced bike mechanics, a wry smile here. Good hunting, j.
 
iis_iis said:
Just watched the vid again, the down shift from 3rd to 2nd made hardly any real change on the output shaft sprocket displacement, you would think a change in ratio would see a change in sprocket net position?
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I dunno whether that's always the case Jon. If the dogs on the gears happen to be in the right spot it could just slip into the next gear with hardly any rotation of the sprocket.

I'm running out of ideas too. Let's hope the endoscope reveals something.
 
Agreed Cam, matter of what aligns as the selectors move, perhaps someone has a case open with gearbox and selectors working, is only one fork in motion as you select from N to 1st? Even with a scope for viewing the action mostly occurs on the upper half drum and slots, may be able to see more from the crank case breather cap ( removed ) with electronic viewing device.... mostly educated and uneducated guessing from here....j
 
I used to get a hard stop between lower gear changes years ago, occasionally, put down to fewer teeth in the dogs on earlier bikes compared to RGS boxes. Just a random block that would stop a change, All it needed from me was to reduce foot pressure and go again to get a complete gear change. I haven't noticed that in the recent few years. Stupid comment the outer rearset links are not hitting anything or not at 90 degrees. It happens.
 
My 79 Jota lost the ability to go into gears, randomly 2,4,3 etc. No amount of adjustments, previously mentioned above, helped and no external issues were seen.

Cases apart, to find: The previous owner had tried an oil scavenger modification internally that used a resin on the inside of the primary chain case web casting. In an attempt to flow the oil back down to the sump faster.

So after I had purchased the bike, and done many miles, a section of resin had dislodged and got crunched up into broken windscreen glass sized bits, and floated around with the oil inside jamming, and dislodged from gears at will.

Now, before you go bagging out the previous owner, he is a current forum member, and is bigger than you. Hi Phil 👋

Moral to the story, stop fucken around, split the cases and look inside. You never know what you will find.
 
chrisk said:
My 79 Jota lost the ability to go into gears, randomly 2,4,3 etc. No amount of adjustments, previously mentioned above, helped and no external issues were seen.

Cases apart, to find: The previous owner had tried an oil scavenger modification internally that used a resin on the inside of the primary chain case web casting. In an attempt to flow the oil back down to the sump faster.

So after I had purchased the bike, and done many miles, a section of resin had dislodged and got crunched up into broken windscreen glass sized bits, and floated around with the oil inside jamming, and dislodged from gears at will.

Now, before you go bagging out the previous owner, he is a current forum member, and is bigger than you. Hi Phil 👋

Moral to the story, stop fucken around, split the cases and look inside. You never know what you will find.
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Hi Chris,
Apologies.
What was I thinking?
When racing and trying this and that, brain gets a bit delirious.
Late nights, frustration, angry neighbours and occasionally a win.
Stuff worked well elsewhere but obviously not a hot oily engine.
Was from memory, to quieten primary.
Somethings were trick ,somethings not so.
I was bloody lucky.
Sorry boys
Think twice or more, act onc
I promise I have been a Good boy since.

DPO,🫣
 
Wasn't it pretty common to paint inside cases in the good old days? Porosity and all that rot, pip pip.
 
Coming in from left field I had a situation where the end of the return spring worked its way into a position where the leg moved into the gap between the quadrant and the centering pin preventing the quadrant from making its full movement and consequently not making gear selection. Thereafter I always checked the angle of the open end of the spring to make sure it was clear of the quadrant. In this particular case the coiled end of the spring was free to float from side to side altering the position of the open end. As a safety measure I shimmed the coil end to prevent end float. Problem fixed.
Could also be worth checking the cam spring, but as mentioned means splitting the cases.
Good luck.
 
There is a note in Andy Wagner's manual about bending those legs slightly Chris to clear the gap in the mount, I did that and managed to twist the orientation of the spring. I replaced it after my attempt at that bend. Didnt try that again. Those spring legs can block the gear change if they get in the way.
 
Vince said:
Wasn't it pretty common to paint inside cases in the good old days? Porosity and all that rot, pip pip.
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It was.
The crankcase of a friends Henderson 4 was painted inside.
And, repeat, Norton used to coat the inside of the Commando crankcases, at least some, with Araldite.

Paul
 
Reunited Chris said:
Coming in from left field I had a situation where the end of the return spring worked its way into a position where the leg moved into the gap between the quadrant and the centering pin preventing the quadrant from making its full movement and consequently not making gear selection. Thereafter I always checked the angle of the open end of the spring to make sure it was clear of the quadrant. In this particular case the coiled end of the spring was free to float from side to side altering the position of the open end. As a safety measure I shimmed the coil end to prevent end float. Problem fixed.
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... that has happened to me (spring interfering with the quadrant movement)
 
Vince said:
Wasn't it pretty common to paint inside cases in the good old days? Porosity and all that rot, pip pip.
Click to expand...

Loctite have a process for impregnating porositities with a sealant under vacuum. A bit more high-tech than paint.

cheers,

bazzee
 
the cam chain blade post 37, does not look good, although it is not broken, the chain has ground off metal at its lower edge, this can be prevented by giving the blade a little bend as I said earlier, what about looking at the plastic chain guide at the exhaust side as I mentioned ? not easy to see, but easy to damage when fitting the cylinders.
CLEM
still think its a bit of crap under the selector drum, go fishing/borescoping
 
Wow. This thread just saved my day - after a long time ( 1 year for reasons of being 3000K away) I took the Laverda out for a test run and it wouldn't shift up to anything north of Neutral or 1st. I had last year adjusted the shift mechanism as the eccentric locking nut had worked loose. I should also mention I changed out the Neutral selector switch under the engine with a new one at some point after that? So... today - I took off the gear selector side cover and tried to hand select gears while watching and still no success. Just seemed stuck. Then I came in here and found this thread about "Have you removed the neutral switch? The plunger might not be retracting, and stopping the selector from rotating past it.".

I went back out to the garage - removed the NEW neutral switch I had installed last year and voila - I can hand select gears through the range. The top of the neutral switch showed fragments of brass where it had been meeting some force (e.g. shift attempts). Thinking I may try the old neutral switch or space the new one lower. Next up is to adjust the gear selector eccentric w/out the Neutral switch in the picture. Get that right (using the 4th gear method of adjustment). The weird thing is I would have test ridden after the neutral switch and the gear adjustment so not sure why it didn't have a problem 1 year ago but did today. Oh well. Thanks and I'll keep you updated on progress.
 
And don't forget the rotate the rear wheel back and forth as you click through the gears during checking and adjustment with the cover off.

I cured the issue of the spring fouling the selector arm and eccentric adjusting pin by grinding a subtle groove in the eccentric that prevents the arms from moving laterally - has no effect on spring tension. prior to that i was using a thin custom-shaped 'shim' to keep the spring away from the dreaded gap.Selector eccentric customise.jpgSelector spring retainer.jpg
 
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I've been messing around with clutch, chain and gear selector adjustment on-and-off all summer, trying to resolve constant gear change issues, changes up or down often requiring two or three stabs. A replacement selector dog-leg spring has sorted it, the original had gone soft and very loose on the shaft. I now have a very sweet gearchange. This was a cheap and easy fix, so is worth eliminating if you're having issues.
I bought the dog leg selector spring from Motalia UK which seems fine. As a precaution I also bought a replacement selector hook, but it had to be returned as it was laser cut and the tips were unfortunately lopsided and jagged. The replacement also went back as it was the same, but crudely filed down. Motalia were OK about the refund and I have no beef with someone who is trying to support owners, just a suggestion to look elsewhere if you need the selector hook until their supplier sorts the issue.
 
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