lost first gear

acelav

acelav

Junior member
Location
ynys mon
clutching at straws:unsure::unsure: got the bike back on the road after a rework on the styling side and only got about 2 miles down the road when I could not get it into first gear second and the rest were ok but no further down than neutral, I've tried the selector shaft position that's ok taken out the neutral switch still no good:cautious::cautious: any other idea's before I take the engine out of the frame and pull it a part, another question could you split it upside down to get to the gear box ?????? put it to one side in the garage when it happened now I need to sort it🤨🤨🤨 thanks for any suggestions' Stuart
 
Which bike are you referring to? Laverda made quite a few different ones with differing systems.

On big twins and triples, if you think the selector indexing is ok, is the eccentric nut tight? Have you checked selection of every gear, bike on the stand and looking at the teeth on the selector relative to the pins on the end of the selector "drum"? Check spring on the selector.
Yes, twin or triple, you can remove just the lower crankcase, leaving top end in situ.

Paul
 
remove the triangular cover and take out the eccentric screw and locknut entirely, then with the rear wheel free from the ground (so it can be rocked back and forth) see if you can select the missing first gear, if you can then report back.
CLEM
 
If the excentric gear selector is misaligned the result is usually missing 1st or 5th. It's the same if the output shaft is binding on the outer gearbox cover. Do a search on this, there will be hundreds of posts as it's pretty common. It can be frustrating, guess how I know. Do this before any major work.
 
hi Clem tried your advice but still no good can get everything but first, hi Rob that time it was the selector shaft I had miss aligned the marks, but I did learn from that mistake they are ok this time so don't know :unsure: :unsure: :unsure: :unsure: :unsure:
 
OK so you know about need to carefully check alignment marks. Good!

Presumably you did manage to select 1st OK when you first moved off?
What happens now? Does the gear lever move OK? If it does, are you getting full travel? Does the pawl engage and turn the selector shaft? Can you turn the selector shaft using a pair of grips to select 1st?
 
more info. needed from acelav ... anything done to the engine / gearbox?
I'd go with Clems suggestion but substitute 'be prepared to roll the rear wheel (by hand) through the entire gear cycle' to watch the cams at work
having had a similar hiccup it should be an easy fix if you were able to select 1st in the first instance and it is likely an adjustment issue
 
Try removing the cam chain tension adjuster. Then stick your finger in the hole, or take a photo with your phone. If you can see/feel chain, that means the tensioner blade has failed and is lying on the bottom of the gearbox, preventing the quadrant from moving down enough to engage first gear. Consider yourself lucky that you've caught it, before the cam chain parts.
DAMHIKT?
 
acelav said:
Another question could you split it upside down to get to the gear box ?????? put it to one side in the garage when it happened now I need to sort it🤨🤨🤨 thanks for any suggestions' Stuart
Click to expand...
Yes.
Best to strap the crank to the upper case, because it's a whole lot easier to put the gears and selectors in the bottom case and lower the rest on when you're re-assembling.

Halved Case.JPG
 
hey thanks for all the help so far, I will take the cam box cover tomorrow and have a look at the chain tensioner blade, I did have the head rebuilt by Keith. let's hope I don't have to go as far as strip, but it can be done that way, I'll try Robs idea first :):):) another day tomorrow thanks again
 
Others may have different techniques, mostly setting the pawl and ratchet was best done at 4th gear, bit of an art sorting the optimal selector system as i recall. Never had any success adjusting the eccentric slotted adjuster in the 1 N 2 operation. Sock has a perspective i had not seen, good easy thing to check, 5 minutes removing the adjuster post mount assembly ( not the threaded adjuster only ). Did the issue happen suddenly or became worse over time? Happened here recently ie stuck in first all of a sudden. Was an adjustment, also depends on the selector parts state of wear.... as it may assist.

Notable is the scenario, all these wise old Laverda men/mechanics, standing around your bike in a considered fashion, across the planet... amuses me no end....j
 
The Sock said:
Best to strap the crank to the upper case, because it's a whole lot easier to put the gears and selectors in the bottom case and lower the rest on when you're re-assembling.
Click to expand...

Yes. I was about to say the same thing, but you beat me to it. Keep the engine right way up. Remove the primary chain and lift the top half off with lifting slings around the ends of the crankshaft. Crankshaft stays with the top half while clutch and gearbox remain in the bottom case.

2 halves.jpg
 
update!!!!! I've taken out the Cam chain tensioner as the sock suggested and the blade is there can't see the chain so it's in one piece also can select second to top with no problem with just my fingers on the shaft nice and easy, so I guess it's time to think about taking the engine out and have a look at the gear box internals, or any other things to try before that:unsure::unsure::unsure::unsure::unsure::unsure:🤞🤞🤞
 
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