I know what you’re thinking; why doesn’t this clown finish the timing chain replacement tutorial? I would if I could, but I have run out of good photos so I can’t finish it. I am in a life-limbo situation at the moment, to the point that I don’t own any bikes!(*gasp*) Yep, no AG200s – therefore no pics! Before I had a clean-up though, I did take some snaps of some other projects so I will move on to what I can until I get my AG mojo back! Yes, it will be back…
If you follow the comments closely, you will know that I think the AG200’s clutch is a weak point of the bike. I suspect Yamaha knew it too, that’s why they upgraded it on the TW, TTR & XT. Luckily the AGs gearing is pretty low so there isn’t much strain on it, but if you up the gearing or strap on a load you may feel the clutch struggle, especially if its already had its share of usage. It’s not hard to service or repair so lets take a look…
We probably should look at symptoms first. They’re pretty obvious; if you give your AG the berries and the revs rise and you don’t accelerate at the neck-snapping pace you are used too, then there’s a good chance your clutch needs looking at! Is the clutch cable and lever adjusted properly as per the manual? Look at that first. They are prone to shudder too, and gearing them up for a better road speed will amplify it if you didn’t notice beforehand.
What you have to remember with the AG is that there are five friction plates, four steel plates and four miserable springs holding the whole show together. Not a lot of surface area or spring tension when things get tough. So if it gets abused, heat builds up quickly and your steel plates warp. This is especially true if you have been riding it around for a while with the clutch slipping.
This tutorial is about servicing the standard clutch with factory Yamaha parts. They are relatively cheap, easy to get and will last OK in standard form if the bike is not flogged or ridden by a teenager (same thing really!) who thinks they’re Jeffrey Herlings! If you want to upgrade it then that’s a bit more difficult. Yes you can put better plates and springs in it from another model but you still have the limited amount of plates. I will cover a more serious upgrade in a future post.
So, what do we need for the job? That depends. If your clutch is slipping then you will at least need the five friction plates and springs. If you noticed shudder before slippage then replace the four metal plates as well. You can of course measure the warp of the four metal plates like they say in the manual but a bit of advice? Do the lot or you will have unsatisfactory results. Yes, it might not slip any more but shudder sucks…four metal plates dude…like I said it depends…on how tight you are!
Take a good look at the parts breakdown posted here. There is a bit of a trap here for the unwary. The unwary parts guy I should add! Four of the friction plates are the same but you will notice that the third or “middle” friction plate is different. Make sure you get this plate, you will notice it has a different part number. I have seen casual parts guys just order five of the first friction plate labelled “8” which wont work. This middle friction plate is modified to accommodate the Boss Spring (19).
If you’re doing a budget repair then the friction plates and the four compression springs will get the whole thing working again. I strongly recommend you do the whole thing or you will be disappointed. Four of number 8, one of number 18, one of 19 and four of 9. Four pressure springs (11) will also be needed as well as a case gasket. I know it sounds like a lot but it responds well to all these parts and they are not that expensive from Yamaha. Get a price on a WR or YZ clutch rebuild while you are at the dealer if you want to make yourself feel better about it!
When you know the new parts are going in, it pays to let the new friction plates soak in the same oil as you use in the engine. Overnight is good. As always with engine related work, its a good excuse to do an oil change, especially if the clutch has been slipping as it would of been dumping the fibrous friction material into the oil. Remove the filter and the cover from the cases.
When you have the oil out, there are a few bits we need to sort out before we can get the clutch cover off. Undo the two bolts holding the foot peg bracket. You can remove the top one and let the whole assembly swing down if you want. Once we have this bracket out of the way you can slide the rear brake lever off its shaft and out of the way. You will have to remove the return spring first to achieve this. If the rear brake light switch is still around you will need to disconnect this as well.
Once all this stuff is out of the way we can remove the kick starter. Add a kick starter shaft seal to your list of parts if it looks like it’s been weeping oil. Once the bolt has been removed from the kick starter, you can slide it off. If it’s a bit tight you can lightly tap a screwdriver into the split section of the spline to separate it and help it move.
Now that everything is out of the way, we can remove the ten screws holding the case on to the engine proper. Take note of the different lengths and you may need a few gentle taps from a soft faced hammer to break an old gasket. Take note in the photo at left that the o’ring from the filter housing is still in place, it would be a good idea to remove this and keep it with the filter and cover to save it getting misplaced.
Now we can remove the cover, slowly pull it away from the engine keeping an eye out for anything that drops out. What can drop out? Hopefully only the locating dowels! You are in trouble if anything else falls on the floor! It’s probably a good a time as any to take a look at both gasket surfaces and clean them up with a gasket scraper. Note the locations of the dowels at the front and rear of the engine. Remove them if they will come out and stick them in the recesses in the cover once you have cleaned it up and put it aside.
OK, now it’s time to have a look at the clutch. Undo the four 8mm bolts holding the compression springs in. Move across diagonally and remove them a bit at a time to spread the load across the pressure plate. Not really a critical process on the AG but it makes good practice if you ever work on more exotic stuff in the future.
Now that the compression springs are removed, it’s time to release the pressure plate. Take a look at my pic at the right and keep an eye on two things; make sure the o’ring on the push-rod is OK, and watch the push-rod ball does not come out and get lost. If you’re paranoid like me (watch for my upcoming blogs on bug-out preparation 🙂 ), use a magnetic screwdriver or other device to remove it and put it aside so it doesn’t get lost.
Now we can remove the plates. One should probably be careful here and keep the plates in order but what the hay, you’re replacing all of them right? Right?! If not, feel free to go and check the clutch section in the service manual. Three things are critical for normal operation; compression spring free length, friction plate thickness and steel plate warp limit. It’s all there in the manual which you can download here or you can buy your very own exclusive copy from eBay here! All that info in one place for 10 bucks, how did this Polish guy pull that off? What a legend! 🙂
Just out of interest, I thought I’d post up a photo of the springs out of the bike I was working on at the time. This AG’s clutch was slipping in all gears and was useless. Check the difference between new and old springs. Not much difference eh? But it was a enough, together with under-spec friction plates to make the bike unusable. The AG200 clutch is a bit like my advice on the carburetor series I did a while back; cut corners in maintaining it at your own risk. Same with the clutch, if you cut corners by replacing one thing like the springs and you will soon have more issues and you will be pulling it apart again. But anyway, you get it…that’s enough on that issue.
Right, back to the grind; the reassembly. Only a few things to watch out for here. Check out the manual or the exploded diagram above, it’s pretty straightforward. Friction plate in first, then a steel plate, another friction plate and another steel plate. The middle, friction plate goes in next, then the boss spring and another steel plate and so on until you have run out of plates to install and there is a friction plate looking at you ready to put the pressure plate back on.
Before we can do that though, don’t forget about the push-rod ball. Once that’s located we can slide the push-rod on the pressure plate into place and line the plate with the spring posts and we are ready to install the new springs. I like to bring the tension up on the springs as evenly as I can in a cross pattern. A few turns on each spring and then move across to an apposing spring. The torque on the compression spring bolts is low at 6Nm, so don’t get heavy handed with them or you will break a post or strip out a thread – scrap one clutch!
The last thing we need to do before taking sunshine away from the clutch assembly is adjust it. The service manual explains it well but the rough and ready version is to take the slack up on the push-rod (move the tip of the arm towards the front of the bike) and make sure the sharp end of the push arm assembly aligns with the post/mark cast into the engine case. If it doesn’t, loosen the 10mm nut in the middle of the clutch pressure plate and adjust the screw in the middle until it aligns. Nip up the lock nut when you’re done.
Not far to go now folks! Grab the front and rear dowel pins and install them in the engine side of the cases. Install your gasket in the same place so it hangs on the dowels and you are ready to place the clutch cover case back on the engine. Keep an eye out for the earth wire and the starter motor cable locating tabs shown at left. The rest is pretty much the reverse of the disasembly. 8Nm on the engine case bolts, make sure your rear brake is adjusted when you put it back together and don’t forget to put some nice, fresh oil back in the cases!
That’s it, we are done. Now you can go out and at least be confidant that under standard conditions, your clutch will do the job. Keep Jeffrey Herlings off the thing though!