Triumphrat

RexxyPup · 06-05-2009, 01:04 PM

So I thought I would write another ‘how I did it’ pictorial following my investigations into a ‘tonk’ noise in the transmission. This didn’t solve it (solving that will hopefully be followed by another on these on repairing a gearbox!), but I did have fun doing it, and hopefully can make life easier for others out there that need to do this.

First off, the tools

¼” drive socket set for the cover bolts
½” drive socket and Torque wrench (can’t remember the exact size but will update this after the gearbox repairs) for the clutch basket nut
Impact Driver for clutch basket nut
Stanley blade to scrape gasket surfaces clean
Partner (use your own!) to stand on brake pedal
Calliper for measuring friction plate thickness
Feeler Gauges and glass sheet for checking plate warp
Special Triumph Clutch Basket locking tool (borrowed from Performance Triumph – Swindon – Thank you!)

Getting Started

Okay, so the first basic is to get the bike secured and ready, with side and bottom panels off and oil drained. I worked on mine on a lift, with the front wheel secured, but I didn’t disconnect the battery. Some may say this is wrong, but as nothing electrical was disturbed during the job, I wasn’t worried.

I should say here that from the outset I followed the manual, and that at a couple of points I did wonder why I was removing one or other of the engine covers as it seemed possible to only separate two, however, it’s no big deal and does make the job easier.

There are three types of M8 bolt used around the engine covers, and it is important to make sure that you note where each comes from

As you can see, the majority are all the same, there is one with an additional washer flange and the location of this is marked in the relevant picture below. I didn’t realise until midway through removing the covers, that mixed in with all the standard bolts were three longer bolts with unthreaded shanks. I was able to work out the location of two of them during reassembly. So if you do this job, and make a note of where they actually came from, please let me know

One final comment before getting on with the job; all the casings have little tabs cast into them around their periphery that correspond with similar tabs on the engine itself. If you have to use a bit of leverage to ease the covers off, please use an appropriate pry between these, NOT between the actual mating surfaces, otherwise at the very least you will have a 70’s Triumph that needs a drip tray.

RexxyPup · 06-05-2009, 01:04 PM

The first task is to release the clutch cable from the release arm on the top of the clutch cover. I marked both adjusters with a dab of paint and recorded the number of turns on each so that I could get straight back to the setting when rebuilding, before slackening off the adjustment at the lever and clutch housing to free the cable. Put pressure towards the front of the bike on the clutch release arm, ease the cable nipple out of the arm and let the arm swing back to its resting place.

Now remove the starter motor gear casing by undoing the M8 bolts around its periphery, leaving two locating dowels in the engine. The picture below shows the gears in the engine, but the big one came out with the cover and I stored it like that until reassembly. I’ve shown it back on the bike to show the yellow painted (one side only with the colour faces the casing) wavy washer there to preload the shaft.

The next step is to remove the crank casing cover. The first oddity to note here is that there is a bolt totally unlike any other in this casing, and I have marked it with a red ring on the photo. It has a large shoulder washer integral with the normal shaped head that Triumph use. Why it is there, I have no idea.

Remove all the bolts round the crank cover, keeping an eye out for those three odd ones I mentioned earlier. When I removed this cover, the small gear shown top right stayed in the engine, but its blue painted (again coloured side towards the cover) stayed stuck to the cover, so make sure you recover it!

With the crank cover removed you can get at all the bolts holding the clutch cover down. Remove all the bolts noting where the odd length ones (with an unthreaded shoulder) came from. I’m sure about the lower left location, and reasonably comfortable with the mid right location, but the top was a pure guess. Let me know!

And here’s what we are trying to get to; the Clutch Assembly

RexxyPup · 06-05-2009, 01:05 PM

So the next step is to remove the pressure plate by undoing the 5 bolts with springs under them, and sliding it off. At this point you can remove the clutch pull rod (or lifter piece as the parts fiche lists it), remembering which way round it went. This should give you access to the clutch plate pack as seen in the next picture. Note that the last plate in the pack sits between a different set of fingers on the basket to all the other plates.

You can now ease the pack of clutch plates out from the basket, but you need to be careful to maintain the order and orientation of all the plates. I was lucky. On the plates with the friction patches there is one tab on each plate with some manufacturer’s markings, and all mine faced the same way. With the all metal plates, you can see that they are stamped out of sheet, and so one surface has edges that are slightly rounded, while the back face has razor sharp edges. Again mine were all the same direction. So here are 3 pictures for reference …

My stack of plates as I removed them from the basket

This next picture shows the 3 types of plate in the pack so you can tell them apart. From left to right, there are two of these that start and end the clutch plate pack. The main visual differences from the mid pack friction plates are that the ring carrying the pads is not as wide as the mid plates, making the material pads look quite squat and square, the plates themselves are thicker and slightly darker in colour than the other friction plates, while the next plate is the all metal ones, which alternate with the material coated ones. Lastly, the mid-pack material coated ones that alternate with the metal ones. Note the material pads on these look tall and thin compared to the first plate type in the picture.

Here I have fanned the stack out like a deck of cards so you can check the correct order, which starts with an end plate, then alternating metal and friction plates, and finally the other end plate. Bringing up the rear are two thin washers, one an anti judder spring washer and the other the anti judder seat washer. These sit inside the diameter of the end plate

RexxyPup · 06-05-2009, 01:06 PM

With all the plates out, you are left with the clutch inner and outer basket, fastened to the end of the gearbox input shaft with a collared nut. It is worth reassuring you that at this point I noticed that I could move the outer basket up an down by about 0.5mm. This apparently PERFECTLY NORMAL – DON’T WORRY!

You can just make out the collar on the nut as a thin silver ring around the end of the shaft. In other bikes there would be a sort of key way in the side of the shaft that this thin collar could be punched into to prevent the nut turning, but Triumph doesn’t do this. The collar always faces away from the shaft (mine didn’t). I used an impact wrench to undo this nut as it is pretty tight, but it is possible with the bike in gear and someone standing on the rear brake, to use a large breaker bar to undo this.

Behind the nut is a belleville (yup that’s what it’s called in the manual) washer stamped ‘out’ (for correct orientation). Remove the washer, and the clutch inner basket can be removed to reveal a thick spacer/thrust washer.

With that removed you can now see the slightly complex looking arrangement of locking rings and sleeve, but a gentle pull on the basket will show which is the sleeve. The sleeve needs to be removed before the basket can be completely removed. I found this easiest using a magnet and a gentle slide back and forth action with the basket. The sleeve slides out.

RexxyPup · 06-05-2009, 01:06 PM

With the sleeve off, there is enough free play to ease the two parts of the basket out from behind the crank casing. Here is the side of the bike stripped down, with the oil pump drive driven from the back of the outer clutch basket by six steel pegs.

Here are the basket assembly parts in the order they go on (or come off).

So there we have it, a completely stripped down clutch.

RexxyPup · 06-05-2009, 01:07 PM

There are some things to check before reassembling. First, there are some springs embedded in the back surface of the outer clutch basket. There are three types

4 Green marked springs of a thin-ish diameter wire that fit the full length of their slots
1 Blue marked spring of slightly thicker wire that is slightly short of its slot length
1 Red marked spring of thick wire that is significantly short of the slot length.

These are there to absorb the drive take-up, and irregularities in the power pulses. Under normal load the four green springs do the work. Crack open a good proportion of throttle suddenly and the blue one adds its strength, and for a more fierce throttle opening, the red one also comes in to play.

Check that these springs are all complete and none cracked or broken (it has been known) as when they do break the pieces can fall into the gearbox!

Check that the outer basket is firmly attached to the plate with the springs in. Again it has been known for them to become loose.

Now you can check each of the plates in the clutch pack. Here are the guidelines from the workshop manual, first checking the friction plates for thickness with callipers…

Friction plate thickness: Outer and inner
Standard: 3.80mm 0.00 + 0.08mm
Service Limit: 3.60mm

Friction plate thickness: All other friction plates
Outer and inner Standard: 3.30mm 0.00 + 0.08mm
Service Limit: 3.10mm

Then checking all plates for warping by placing each plate individually on a flat surface (I used a sheet of glass) and try to push a feeler gauge between the plate and glass at various points around the plate. The standard gap is up to 0.15mm and the service limit is 0.2mm. If you can get a feeler of this size under any plate, replace the whole pack.

Finally, give the fingers of the clutch basket a good check over. They will show little square pits of wear where each of the plate tabs sit and move, but you are looking for areas where there are ridges that could stop the movement of the plates. Find any of those and you are looking at a replacement basket (megabucks) or a very light touch with wet and dry (not recommended)

RexxyPup · 06-05-2009, 01:08 PM

So time to reassemble. It goes back together pretty much as it came apart. There are a few handy tips to make it easier, and one specialist took needed – Triumph’s clutch alignment tool

I have a theory that if you are going to throw a clutch away that you could take 4 or 5 pairs of plates, rivet them together and make your own, but I’ve not had the chance to find out yet, and the folks at Performance Triumph in Swindon have been kind enough to lend me theirs (and it’s not the first special piece of kit they’ve kindly lent me either).

Before we start, get that neat stack of correctly ordered and aligned clutch plates you have on the bench and put them in clean oil to soak before being fitted!

So put the outer basket back on the shaft and ease the sleeve back into the gap. Rotate the basket gently to get the toothed edge to mate with the crank flywheel. Now you should have the basket meshed, and centered on the shaft with the sleeve, but the sleeve isn’t home yet, and we need to get the oil pump drive lined up first. With gentle pressure on the basket, reach below and behind it to grasp the oil pump chain and lower sprocket. Gently rotate it and with the light pressure on the basket it should, when the drive pins for the pump line up with the holes in the back of the basket, snick smoothly into place.

The sleeve should also now slide smoothly back with little or no additional force. You can tell when the sleeve is correctly fitted as it should look flush with the locking rings in the basket, and you should be able to see a small groove in the output just inboard of the splines

Now it’s on with the thick spacer washer, slide the inner basket onto the splines, put the belleville washer on with the stamped word ‘out’ facing towards you and put the nut on with the thin collar facing you. The workshop manual says to replace the Belleville washer, but the Gerry at the dealership said not to bother. You choose.

Now insert the Triumph Tool into the space between the two clutch baskets to lock them together, put the bike into second gear and have someone pressing the rear brake pedal, and tighten the centre nut to 105Nm. Take the bike out of gear, remove the Triumph Tool and check that the inner basket rotates freely (and with it the rear wheel).

Now you can refit the clutch pack in the order and orientation that they came off (last time I’ll mention that – promise) starting with the anti judder seat washer and spring washer, until you reach the last plate which doesn’t go in the deep slots between the fingers, but sits in the slots in the top of the fingers (see earlier picture)

The next step is to replace the clutch pull rod, and reattach the pressure plate with the 5 bolts and springs tightened to 10Nm according to the book. This is a very low figure, and I have yet to find a reliable wrench (that doesn’t cost the earth) to do this, so using some common sense, and recognising that the screw into aluminium, I equate this to gently pinched down.

Okay, so that’s the clutch reassembled, and it is on to the covers, making sure that you have cleaned all mating surfaces of any old gasket or crud and are using new gaskets all round (no sense in skimping here they are about £25 all told, and you don’t an old timer coming up to you and saying, “yup my old Trumpy used to leak just like that!”, do you!) and that the locating dowels are all in the correct holes,

So covers in reverse order, starting with the clutch cover. You may need to ease the clutch arm around to engage the lift pin as you offer up the cover, remembering to put the spring washers back where they came from, as described above in the taking apart section, and making sure you put the different sized bolts back where you noted they came from also and tighten them down the same amount as you did the pressure plate bolts (10Nm). Not forgetting of course, to fit the clutch cable bracket back under the bolts it came from.

So now you should have a buttoned up engine, so fill it up with fresh oil, and then get on with the last job…attaching and adjusting the clutch cable. Swing the clutch actuating arm around and insert the cable end, and then return the adjusters at both ends to the position you recorded when you started all this. You should have 0.4-0.8mm of free play at the clutch lever when done. Operate the clutch several times, and go test it!

There… was that as bad as you thought it was going to be?

Triple Ripple · 06-05-2009, 03:20 PM

Excellent write up. Well written, easy to follow with great photos

: You've made a daunting job look almost easy. My vote is that this be put into the maintenance tips & tricks.

My complaints of clunky shifts have gone away with my engine rebuild. Some of the clutch plates had dry spots (hard to believe for wet clutch). They were well soaked before reassembly and now the shifts are ultra smooth and quiet. Whether that is the marginally increased mileage or the soaking or both, I do not know.

Thanks Rexx

DaveM · 06-05-2009, 04:29 PM

Hi Rexxypup

once again you have done a brilliant post and thank you because I know you have put a lot of time and effort into it.

:

:

I was thinking the same as Triple Ripple.

We will leave this for a few days out here and then I think Don or I will move it into the "maintenance tips & tricks" subforum which is where we will keep it.

thanks sport
DaveM

redmosquito1 · 06-05-2009, 05:17 PM

excellent write up rex. I will have to book mark this as I'm due for a new clutch pretty soon.