Tiger Explorer 2015 Explorer Gearbox Fix

My 2015 Explorer has been suffering with missed gears going up the box in particular 4th and when coming down the box going straight to neutral from 3rd.
This was totally spoiling a great bike, as you spent the whole time trying to find ways of riding round it, though it would always change up if you had more than 4000 rpm.
After reading as much information as I could on the internet, I found it was a common complaint, and that Triumph had produced two or more modified gear change shafts, but no recall.
So having purchased the relevant parts, I thought I would post how I got on changing it to help others
Here is the patient.

 

The first thing to do is remove the cover over the expansion tank which is held by 3 torx screws, then you can take out a 2 more which hold the tank, allowing you you to swing it out on its hoses.
I found by tilting it, I could remove the hoses and tank without any spillage, though I did put a bung in the hose when it started to dribble.

 

The gear lever can now be removed, making note of the punch mark lining up with the split in the lever, I held it out of the way with a cable tigh to the foot rest hanger.
Now you have clear access to the gear change cover.

 

I put a little mark on the cover, normally tipex but it had dried out, just to make sure things looked right on reassembly.
The next thing is the starter solenoid at the top, this just pushes out of its rubber sleeve and lays on top of the engine.
Now we can start to undo the 8 mm bolts, the top 2 that hold the solenoid on mine were a little bit tight due to corrosion, so I was careful to wind them in and out as I went , tapping style.
The bottom right hand bolt is longer and has a copper washer gasket.

 

In the centre is the gear possition switch, which can be detached via its plug next to the solenoid, the plug is one where you lift the clip rather than push it down.
The switch has locating pin that spins round and locates in the end on the detent shaft, this can now be removed.

 

Next I replaced the 2 bolts that hold the gear switch in place, just more than half way in, so as not to damage the threads and used them to pull the cover off.
Note I put tape round gear shaft spline to save the seal.
It took a bit of gentle wiggling, and I thought the right hand Dowl was the issue, but actually it was the gear shaft seal, and a spot of WD40 and the cover came straight off

 

With the cover removed, the first thing to do, is recover the washer from the end of the shaft, just in case it drops into the engine, which would mean removing the sump!!!

 

The shaft also has a washer at the other end, and this is the tricky bit, removing the shaft with a steady hand, playing operations as kid will of helped.
I used an arial type magnet as back up, which works great.

 

With the shaft removed I decided to replace the detent wheel as well, as it's going to have worn with the old shaft, a bit like your chain and sprockets.
An 8mm bolt that MUST be replaced by a new one, simply undoes ,no need to lock anything up, and you can wiggle the wheel and it's holder off.

 

Now with everything on the bench, time for a cuppa and look at what we have...

 

The old shaft showing slight ware on the hooks, but the new shaft has hooks 2.5 mm longer, which will make much more positive engagement with the detent I hope.

 

The old shaft showing slight ware on the hooks, but the new shaft has hooks 2.5 mm longer, which will make much more positive engagement with the detent I hope.

 

Here is the side by side shot, and the new part number.

 

Now with my box of parts I can build up the new shaft using the old one as a pattern.
And change over the detent wheel, which needs a wiggle over the role pin to get fully home.

 

Now time to clean up the gasket faces carefully, a little bit of brake cleaner eases the stubborn bits.
Replace the oil seal in the cover, the old one looks fine, but for a couple of pounds why risk it, the same goes for the oring on the gear possition switch

 

With everything cleaned up, I replaced the detent wheel using a new bolt, everything locates on pins so you can't get it wrong, and torqued it to 12 Nm , again nothing needs locking up.
Next I made sure both cover dowls were in the engine side, and lightly coated the new gasket with multi purpose grease, just in case I had to take it off again!

 

Next will the assembled Shaft, and inner washer ON the shaft as opposed to Triumph saying hold it in place with grease.
Direct it towards the rear bearing till the detent wheel touches the front of the wheel, then ease it up on with a small screw driver, allowing the shaft to continue back into its bearing.
I used the Arial magnet again as piece of mind, and a headlamp is useful for seeing what's going on at the back while you're hands are full.
It is important that the detent spring is at vertical as the shaft goes in as it gets its tention from the right hand side of the engine case.

 

Once in the abutment sleeve can be relocated using a small Philips screwdriver up the inside.

 

Now the cover can be replaced, but first I gave all the new parts a coating of oil using clean engine oil, just they don't start off dry.
Next put some tape round the shaft spline to protect the new seal, and some oil won't hurt either.
With the cover back in place, replace the bolts to their original homes, a coating of of copper slip on all but the long bolt with NEW copper washer.
Don't forget the solenoid bracket before you put the top 2 in! Yes I did ☺️
Then it's the gear possition switch with NEW oring.

 

Now just plug in the gear switch, and replace the expansion tank, and cover.
With the gear lever reconnected, and the punch mark lined up, check the gear change while rotating the rear wheel forward.
Hopefully a lovely crisp change