Gearbox selection changing down - LM.

I have now fitted a second (spare) gearbox on my Le Mans, and they were both built by Nigel at NBS, so I would believe that they are built correctly.

I understand that the gearbox on these Tonti framed bikes was not made or designed in a Swiss watch factory, but coming down the gears, I am hitting either false neutrals or finding that I am having to stamp on the gear change lever to get the gear engaged. Is this normal?

Does anybody have any experience of adjusting the pawls via the nut on the back of the gearbox that they can share?

I have rear-sets on my Guzzi, I was wondering if the ratios had been altered by the re-design of the linkage? Has anybody ever heard of this as a problem?

Or should I just shut up, practise more and live with it?

Awaiting experienced advice.

Never tried it (never needed to) but the adjustor on the rear of the box is for just that purpose.Re the rear sets. The lever on the end of the gearbox should be at 90 degrees to the rose joint bit that pushes on it so as to give equal up and down movement. I gues the same applies for all the junctions.From what I have read about the adjuster, Move it no more than 1/6th of a turn at a time. Write down which way you moved it, then go take the bike out to see if it is better or worse. If worse then go the other way. Write it down again and go try the bike. If better, try another 1/6th of a turn etc.And never turn it more than 1/2 a turn in any one direction or the spring will come off.

A. is pedal going down far enough (something stopping it going all the way?) B. are you simply trying to change gear too fast? C. must be correct amount of free play in the clutch cable. In the past I’ve made the mistake of overtightening the h/bar clutch cable adjuster while on the move, I. to make getting neutral easier once clutch is hot, only it doesn’t help at all actually; and furthermore, II. it makes gear changes more difficult with more off or more pronnounced false neutrals.

Don, the gearbox lever on mine coming off the splined shaft points down by about 30*. I’ll see if I have enough adjustment to get it to 90* to the rod. Good point!
Thanks for the advice re the adjustment. I’ll go carefully.

A. Pedal is not obstructed.
B. Possibly
C. I’ll look at all of this again, but I think it’s ok.

That could be it


I’ve changed the lever from the gearbox shaft to be at 90* to the linkage and…it’s a different gearbox! It’s gone from a clunky, false neutral ridden, needing a big boot to go down the box, to a slick, yes I said slick gearbox which is a pleasure to use. (Maybe not Japanese slick!).
When I was riding it the other day I thought, “I know that they’re not supposed to be good, but this is appalling.” I couldn’t understand why it was so bad, especially after Nigel had built it for me.

So a big thank you from me for highlighting this. I am, as you can probably tell, a very happy man.

If we ever meet, I owe you another beer.


Good job, Guzzis are simple BUT have to be correct, it is the same with the clutch arm and free play as well as the brake levers. The gearbox selector arm is even MORE critical on rear sets OR the heel toe gearchange.


I was going to suggest having a ride on the Spada to see what the Guzzi box should be like. Glad you got it sorted.

Following this thread I have reset the linkage on my 850-T3 Cali. I could not get it to have enough movement with the gear selector lever at 90 degrees but by moving it down by about 10 degrees she is selecting all gears and neutral nice and cleanly now. Previously the lever was at about 30 degrees so there is a significant change. I also noticed that the journal for the rose- joint to attach to is not made square to the lever so there must be some special Guzzi magic going on here. Anyway, thanks for all the info and I am looking forward to taking her on a run to see what the difference is like on the move.
All the best,
David.CylvaBirch2013-07-07 18:58:51

I concur, Don and the rest of the the Guzzi experts that contribute to these threads really are the men! I decided to completely dismantle the linkage and remove it from the bike for overhaul (OK I admit I polished it all up as well) whilst waiting for a replacement ball joint. When I re-assembled it I followed the 90 degree advice with the same spectacular results. I gear change that I used to have to stomp on now snicks into place with just light pressure from the toe or heel. Absolutely fantastic! By the way I eventually binned all of the ball joints and replaced them with these: -

ball joints on EBAY

nylon lined, rubber gaiter pre-lubricated - very nice!
Richard632013-10-20 20:24:51

That’s very like the standard one on mine, as for T3, but same as Spada, there’s then just a ‘U’ joint and clevis pin (I think it’s called) at the pedal end; never been a problem.

Those joints look good, shame they are not available in Stainless. I should probably add the same job to my winter list.How about a picture of the new set up.

Rose joints are better, and come in stainless.

Got mine from McGill motorsport made a huge difference to the heel toe however over the years I find that a fair bit of free play on the heel toe works better, mebbe tis my big feets. BUT I get 1st with hardly a sound, so much so that I often hit the lever 3-4 times I have NO massive BANG as it goes into gear.

If I get a chance at the weekend I will take a picture and post it (may as well put all that polishing to some use!) Agree with the comments about stainless. I am hoping the zinc coating will stand the test of time. OEM joints did not appear to be stainless but I could be mistaken.

Hi everyone,

Here are some photos of the linkage with the new ball joints in place. Note the rubber gaiters that prevent ingress of road dirt into the joint. You can see that I have followed the advice given in this forum and set each joint to as close to 90 degrees as possible. You can’t see it in the pictures but I have also replaced the allen key headed pinch bolt with an ordinary hex headed bolt as it is easier to tighten it with a spanner rather than an allen key. (The word “easier” in the previous sentence is relative - it is still an absolute b!gg*r to get to!). The brown stuff on the exposed threads is copper ease not corrosion before you ask!

Richard632013-10-26 20:08:35

Looks good