T3 Gearbox action

Having acquired my T3 in November after my contretemps with an oil tanker which has kept me off the road for nearly 3 months, I felt able to get it (and myself) on the road for the first time and run the 40 miles over to Llanbister to the Borders and Mid-Wales monthly meet.

Now I know that the T3 gearbox is not the snickiest in the bike world but changing up and finding neutral was a real trial. Changing down was no problem. Allowing the bike to warm fully (it was a pretty cold day) and developing a bit of technique (not hurrying the change, allowing revs to drop to just above tick-over before changing up) seemed to improve matters and eventually I got a 60% success rate changing up first time (otherwise false neutral), but I’m sure it’s far from as good as it could be. The bike has 68K km (42.5K mi) on it.

Prior experience on other bikes suggested to me clutch drag and/or a misaligned/worn selector were the most likely culprits. The clutch doesn’t seem to be dragging at all, so I suspect the latter. Reading Guzziology later backed this up.

My question is: how far off optimum is this behaviour, what’s the best improvement I could realistically get? Or is it really as good as it gets? :frowning:

I think that you have worked out the technique, let the revs drop and don’t rush the gear change. The mileage on these bikes can be considered as unconfirmed as the speedo cables are known to break if not maintained and then who knows how far a bike has traveled before the cable is replaced before its next MOT?

I have not used Nigel at NBS but he comes highly recommended by folk on here for gearbox rebuilds if you live up North, if you are nearer London, Baldrick is your man.

I have not used Nigel at NBS but he comes highly recommended by folk on here for gearbox rebuilds if you live up North

Yes, I used him to replace the clutch on my ill-fated v50 II. I was planning to give him a call but wanted to make sure I wasn’t going to get “they all do that, Sir” first! Good to know the technique is the approved one but I think the change is probably not nearly as good as it could be so I’ll call him. Thanks.

And yes, I accept the mileage could well be fictitious for the reasons you give - my V11 Sport broke several speedo angled drives and ran nearly 5000 mi overall before I managed to clear that issue up (cable routing, what else?). Seems to be a ‘thing’ then…

There is a knack to it, but it should be better than you describe Check the linkages on the back of the gearbox are all operating at about 90 degree angles or you will get different movement with up and down changes, Also see how much slop there is in the rose joints etc.
The next bit is to try the adjuster on the back of the gearbox, read the relevant bit in Guzziology before trying it.

Hi Andy, Met you at The Lion on Sunday.

Gearchanges on big block 5-speeds are generally slow. I find that the best way is, when you change gear, don’t release pressure on the gearchange pedal until after you’ve let the clutch back out. This avoids the false neutrals and stops it jumping out of gear if the box is a bit tired. As for finding (the proper) neutral, that can be a bit awkward but usually comes with practice.

Thanks v7John and DonSpada,

So I should check the linkages and improve my technique before we contemplate surgery…
Roll on warmer weather - I’m no softy but it’s sheet ice outside my house at the mo’ and practice is deferred!
So I’ll do battle with the linkages first: judging by the general quality of work I inherited from the P.O. though, I don’t expect to find too much amiss there.

I did see that comment in Guzziology about not loosening the Detent Centering bolt more than 1/2 turn, or risk the need to disassemble: so I am suitably advised. As down-shifts are noticeably better than up this may be the way to go.

A small voice asks, “But what if the P.O. already adjusted it out 1/2 turn leaving me with no more adjustment?” :unamused: .

Gear changing - one of main reasons why Moto Guzzis have been described as “agricultural” :laughing:

If memory serves, because it’s used to centre the gear shift return spring. Unscrew the bolt too much, the spring pops off. That’s a gearbox open-up job to put it back on. I wouldn’t mess with it unless really really REALLY must.

As down-shifts are noticeably better than up this may be the way to go.

Look to the pedal height. May just need readjusting to your particular boot size. (?) But I typically found the change ups more awkward too.

I checked all the linkages and they are tight and almost like new: I did mention that the previous owner had left me a pretty good legacy mechanically and cosmetically so not surprised really.

Look to the pedal height.

My next step precisely: especially as the left is my bad leg (courtesy of the tanker) and still doesn’t have the full range of movement - need all the help I can get!

Thanks.

I’ve been there. A damaged ankle was one reason I ended up with a V7Sport in the 70s when I went looking for a bike with a right hand gearchange. I did manage to get round it on other bikes by having heel and toe levers made. I even had one on a trail bike! These days all my bikes have a right hand change with 1 up and 3 or 4 down.

Also check that the angles of the connections are set at 90 degrees so the push and pull action gives equal and maximum movement

Does the big block gearbox have the eccentric adjuster for the mid-point of the shift action like the V50 series does? If the shift is good one way but not the other adjusting that might improve it.

NOTE - If it does have one and you’re going to have a fiddle, never turn more than a half in either direction. If you wind it out past the spring there is no way back without stripping the box.

It certainly does Stanley. :smiley:


NOTE - If it does have one and you’re going to have a fiddle, never turn more than a half in either direction. If you wind it out past the spring there is no way back without stripping the box.

Absolute last resort, it’s only to centre the claws relative to the selector drum.