Once a Prototype always a Prototype

I shall call it a P12S. ha

I usually prototype my ideas and if they work, leave them without making them show quality. Below are some scary views of my Frankenstein special. These shots were taken before I started taking the primary apart to get at the TTi 5-speed leaking seal behind the drive sprocket. Really not going to be that much fun to replace the seal. Need a magic hook to get the seal out unless I tear out the gearbox guts, which I really don't want to do yet.

Is it a situation where you can get self-tapping screws into the seal, to pull it out with?

Self tappers do work, if the seal has a metal surround then drill a small pilot hole first, drill size equal to or preferably smaller than the root diameter of the self tapper.

Triton Thrasher said:

Is it a situation where you can get self-tapping screws into the seal, to pull it out with?

Click to expand...

kommando said:

Self tappers do work, if the seal has a metal surround then drill a small pilot hole first, drill size equal to or preferably smaller than the root diameter of the self tapper.

Click to expand...

Thanks for the thoughts. The strongest small 90 degree hook I have worked.

I don't know how many people have worked on a TTi 5-speed gearbox with a Manx mainshaft, but I'm kind of surprised they don't all leak a little given where the lip is on the seal and the use of a spacer over the sleeve gear. The spacer barely rides inside the seal and the spacer ID isn't sealed. It could have been leaking through the ID of the spacer. It wasn't a terrible leak, but it was a leak. So if it dribbles a little after installing the new seal, I'm not going to worry about it. By the way, I turned the spacer around so the seal would ride on a new surface not the old worn smooth one.

Nobody needs to ensure me that is impossible, since a leak where I had a leak is also supposed to be impossible.

Out with the old.


In with the new


I did not replace the little seal on the mainshaft. I may end up regretting that, but there was no evidence of a leak on the back of the clutch basket or around the mainshaft. Besides it's not all that messy or difficult to take the primary off with a dry clutch.

By the way, I drove that new seal in with a 1 1/2-inch PVC coupler I had for schedule 40 PVC pipe. Just the right length, OD, and ID with the spacer in place to get the job done.

Carry on

If the sleeve turns with the sleeve gear, can’t you put the sleeve on with sealant?

Triton Thrasher said:

If the sleeve turns with the sleeve gear, can’t you put the sleeve on with sealant?

Click to expand...

Interesting idea. TTi doesn't use any goop inside the spacer. The spacer is a slip fit on the sleeve gear. The spacer butts up against the inner race on the sleeve gear bearing inside fastened in place by the torque on the sprocket, and it turns with the sprocket and inner race on the bearing inside the case. I'm guessing it shouldn't leak through the inner race face against the spacer, but who knows where oil can get to when it gets hot. I'm underthinking it more than likely.

I'll be test riding it later today to see if it leaks, unless it rains. No more wet weather riding in the remainder of my lifetime.

Here are the sophisticated tools I used for removal and replacement of the seal: lol

The top side shown on the coupler is for driving the seal in without the spacer. It fits over the sleeve gear if used that way. I ended up not doing that, and used the other open end with the spacer in place.