P11 AMC gearbox out, TTi 5 speed going in

It's a work in progress... not done yet.

Step 1: Get the AMC gearbox out of the mounting plates.

Really hoping I can do any modifications needed without taking the plates out of the frame. Could be a little too optimistic.

Step 1 is as far as I've gotten.

Hole where the TTi gearbox will go. More later

Note for the few that are interested in TTi gearboxes:

Andy Molnar (sales@Manx.co.uk) does have the TTi gearboxes in for those that ordered and put down a deposit for one or more last year. He may have some extras in stock for sale. I don't know, I did not ask.

Since I sort of jumped the gun because my gearbox won't be on my doorstep until next week, here are some useless images of the mayhem in my garage.

The larger parts I removed to make gearbox removal easier.



P11 gearbox on the bench. Note the unique shell lug with cutout up top. Position adjuster butts against the upper stud and works really well to prevent the gearbox from moving backward. Doesn't do squat to keep it from moving forward. Usually not an issue though.

Schwany said:

Note for the few that are interested in TTi gearboxes:

Andy Molnar (sales@Manx.co.uk) does have the TTi gearboxes in for those that ordered and put down a deposit for one or more last year. He may have some extras in stock for sale. I don't know, I did not ask.

Since I sort of jumped the gun because my gearbox won't be on my doorstep until next week, here are some useless images of the mayhem in my garage.

The larger parts I removed to make gearbox removal easier.

P11 gearbox on the bench. Note the unique shell lug with cutout up top. Position adjuster butts against the upper stud and works really well to prevent the gearbox from moving backward. Doesn't do squat to keep it from moving forward. Usually not an issue though.

Click to expand...

As that is the Matchless/AJS version of gearbox shell rather than Norton, will the TTi box fit?

Matchless said:

As that is the Matchless/AJS version of gearbox shell rather than Norton, will the TTi box fit?

Click to expand...

It won't be a direct bolt in. Of that I am certain.

On paper the TTI mounting lugs are narrower, so thicker spacers will need to be made to get proper alignment. I also forgot to check on the mounting stud hole sizes before sending off my deposit. That will add to the fun if the holes in the TTI lugs are smaller. Where I might hit a big snag is at the bottom mount. A cross member brace is very close to the shell at the bottom lug. The gearbox may have to go in at a funny angle, or I may have to modify the shape of the plates or add to them depending on what I can get away with. I don't know what the size differences are between the Matchless gearbox and that of an early Commando shell. They do share the same guts, so I figure they must be very similar in size.

Both Andy and I are going on the theory that anything can be made to fit.

Worst case scenario is I'll end up putting the P11 gearbox back in, and I'll have a very expensive TTI paper weight. I'm good with whatever happens.

What other frames do you suppose the box could fit? Asking just in case.

Thomasa said:

What other frames do you suppose the box could fit? Asking just in case.

Click to expand...

Wrong person to ask I am. My knowledge of Norton models would fit on the head of a stick pin.

Based on the few posts I've read here that mention the TTI gearbox, they don't fit into any frame without making at the very least some minor changes, such as some grinding or new mounting plates.

A new TTI standard gearset 5 speed with a kick start is a penny or two short of $4700US shipped to the US from TGA. It is a pricey just in case. An intelligent man would have done more research than I did. I'm not too smart though. I'm one of those I think I can do it types. I have a hacksaw, some big hammers, and delusions of grandeur.

Schwany said:

Wrong person to ask I am. My knowledge of Norton models would fit on the head of a stick pin.

Based on the few posts I've read here that mention the TTI gearbox, they don't fit into any frame without making at the very least some minor changes, such as some grinding or new mounting plates.

A new TTI standard gearset 5 speed with a kick start is a penny or two short of $4700US shipped to the US from TGA. It is a pricey just in case. An intelligent man would have done more research than I did. I'm not too smart though. I'm one of those I think I can do it types. I have a hacksaw, some big hammers, and delusions of grandeur.

Click to expand...

If it comes down to needing some custom spacers made to make things work, I could probably make them for you. I have a lathe but not a mill... just send me a message if that's the case.

I just ordered some 1-1/8" aluminum bar stock (that arrives Monday UPS) for a part I accidentally destroyed in my lathe a few days ago. You're not the only one who makes mistakes,... In this case, I think I just forgot to tighten the chuck on a piece that I was simply trimming to proper height. I got distracted, and in a flash the nearly finished piece was mangled beyond repair.

You can add me to your and Andy's belief that anything can be made to fit, except add the qualification "If you throw enough money at it!"

Schwany said:

Wrong person to ask I am. My knowledge of Norton models would fit on the head of a stick pin.

Based on the few posts I've read here that mention the TTI gearbox, they don't fit into any frame without making at the very least some minor changes, such as some grinding or new mounting plates.

A new TTI standard gearset 5 speed with a kick start is a penny or two short of $4700US shipped to the US from TGA. It is a pricey just in case. An intelligent man would have done more research than I did. I'm not too smart though. I'm one of those I think I can do it types. I have a hacksaw, some big hammers, and delusions of grandeur.

Click to expand...

Are they not cheaper directly from Bruce in Nelson?

johnm said:

Are they not cheaper directly from Bruce in Nelson?

Bike Gearboxes

Like this:Like Loading...

www.ttindustries.com

Click to expand...

Probably, but you have to calculate freight and customs cost to know.
The one I have in the Manx was ordered from Bruce with the low first option and reverse gear pattern for rear facing lever.
It needed some machining to fit. Easier for me than making new engine plates. To prevent box from colliding with frame.

johnm said:

Are they not cheaper directly from Bruce in Nelson?

Bike Gearboxes

Like this:Like Loading...

www.ttindustries.com

Click to expand...

Could be cheaper now days. I did not check. Have to email them to get current pricing. However, TTI was not cheaper when I started thinking about getting the TTI gearbox a couple of years ago. The shipping was very high from down under for the general public buying one gearbox and the difference was a couple hundred lower shipped to my doorstep from TGA. Besides I like dealing with Andy.

Well, that was fun right up until the TTi box showed up. Not even close to fitting for a quick install.

My advice is don't try putting a TTi gearbox in a P11 frame unless you are ready to make a lot of changes. By the way, making a lot of changes is slightly less appealing as one ages. Not sure if I'm ready for it now that it is a reality. Just saying...

Below is what it looks like without doing anything. Looks easier to make it fit than it will be. The plunger spring housing nut is in the way. Couldn't be in a worse location. And the plates don't just unbolt and come out. Engine has to be unbolted and supported with magic to get them out. I do have some ideas for mounting the gearbox that would make the engineering types roll their eyes. More shenanigans later...

I'd think only new engine plates is a best case scenario. And... you get to relive your belt length excitement.

With what I've seen you do with a hacksaw and some creativity, this should be no problem.

Schwany said:

Well, that was fun right up until the TTi box showed up. Not even close to fitting for a quick install.

My advice is don't try putting a TTi gearbox in a P11 frame unless you are ready to make a lot of changes. By the way, making a lot of changes is slightly less appealing as one ages. Not sure if I'm ready for it now that it is a reality. Just saying...

Below is what it looks like without doing anything. Looks easier to make it fit than it will be. The plunger spring housing nut is in the way. Couldn't be in a worse location. And the plates don't just unbolt and come out. Engine has to be unbolted and supported with magic to get them out. I do have some ideas for mounting the gearbox that would make the engineering types roll their eyes. More shenanigans later...

Click to expand...

The plunger spring nut is a dummy. It's only there to make it look like the original box if I remember correctly, & can be removed.

Matchless said:

The plunger spring nut is a dummy. It's only there to make it look like the original box if I remember correctly, & can be removed.

Click to expand...

If that is true, I may actually be in heaven because it would move forward enough to get the clutch in the primary.

Thanks much I'll check into that and see how it looks.

I will probably have to run my oil tubes underneath to aid in getting it closer to fitting in the short P11 primary cover.

t ingermanson said:

I'd think only new engine plates is a best case scenario. And... you get to relive your belt length excitement.

With what I've seen you do with a hacksaw and some creativity, this should be no problem.

Click to expand...

I definitely should make new plates. I'm currently arguing with myself about it.

Yep, the belt length. I should have one heck of a collection of them by the time I get done.

If it was me, I would check on the plunger spring nut situation, then mock up the gearbox in the plates so I could measure the crankshaft center to gearbox shaft center distances to see if you are in the ball park..... then after I found it was going to fit, I'd go out and celebrate prematurely...

Schwany said:

I definitely should make new plates. I'm currently arguing with myself about it.

Click to expand...

For me, by the time I'm done arguing, I could have made the part and moved on with my life.

Schwany said:

Well, that was fun right up until the TTi box showed up. Not even close to fitting for a quick install.

My advice is don't try putting a TTi gearbox in a P11 frame unless you are ready to make a lot of changes. By the way, making a lot of changes is slightly less appealing as one ages. Not sure if I'm ready for it now that it is a reality. Just saying...

Below is what it looks like without doing anything. Looks easier to make it fit than it will be. The plunger spring housing nut is in the way. Couldn't be in a worse location. And the plates don't just unbolt and come out. Engine has to be unbolted and supported with magic to get them out. I do have some ideas for mounting the gearbox that would make the engineering types roll their eyes. More shenanigans later...

Click to expand...

it looks like new plates and machine the gearbox bottom mount would be favourite
Or maybe laminate a plate to the outside of the gearbox bottom mount
Picking up on the mounts in front and above behind the gearbox making the plates a full circle

Schwany, there are several variables here. Gearbox location is determined by primary cover (envelope dictated by sliding disc) and of course, length of belt. Frame, rear of crankcase, and gearbox geometry are the other constraints. If I were you, I'd hire a CAD operator (if you can't do it yourself), otherwise you will have an exhausting run of trials and errors in front of you. Machining of the gearbox casing should be the last resort.

- Knut

mdt-son said:

Schwany, there are several variables here. Gearbox location is determined by primary cover (envelope dictated by sliding disc) and of course, length of belt. Frame, rear of crankcase, and gearbox geometry are the other constraints. If I were you, I'd hire a CAD operator (if you can't do it yourself), otherwise you will have an exhausting run of trials and errors in front of you. Machining of the gearbox casing should be the last resort.

- Knut

Click to expand...

I'm more of a "Cardboard Aided Design" kinda bloke
I chain drilled 1/4" stainless steel engine plates when I built my comdom

I have a handle on how I'm going to do it. I won't be making new plates initially. Maybe sometime in the future if I get a bug up my arse to pull plates off the engine and do it.

The add on 1/4" plates for the lower lug idea has been on table as an option from the beginning. Plenty of large fasteners to make add-on plates strong. I do have to get the gearbox mainshaft positioned where I had the OEM box before I attach a set of add on plates. I'm close now, with only another 1/4" to go forward with the mainshaft location, but it is definitely time consuming doing most of the fit work with files putting the gearbox in and taking it out over and over again. Trial and error is part of life. Thanks for the thoughts though.

Currently wasting my time trying to work around the stock oil pipes. They are in the way no matter the orientation. Shit canning that idea and going to get one of the oil blocks that takes AN fittings.

Notes about the TTi gearbox: There are 3 fake parts screwed on the outside of the TTi gearbox. The camplate detent spring plunger housing, and the 2 camplate spindle screws with washers. The plunger housing is just a big crown nut screwed down on a stud screwed in the case. The two camplate spindle screws are also screwed into the case. None of those parts are functional. Frankly I think TTi adding them to the design is a ridiculous waste. That's just me though.