1981 GS450E Rebuild

[pete]

Hahaha awesome Ken, that's gold! Yet so true...

[pete]

Several beers, some champagne, and some scotch (not all at the same time) means it's not wise for me to be working on the bike tonight. Celebrating my wife's car purchase today, a 2004 Peugot 206 with only 32000 km's on the clock. Still not convinced on the whole European car thing, but she's happy so that's all that matters

I did however manage to stop in at the local Yamaha dealer and pick up a bottle of Yamalube carby cleaner, so once I locate a suitable old or cheap saucepan and disassemble the carbs, I'm right to get them all cleaned up.

[Suzuki_Don]

Next up, my cleaned up and sorted camchain tensioner and new gasket ready to roll:



Note that I have rotated the knurled nut counter clockwise and pushed the tensioner shaft in as far as I can and locked it with the locking screw ready for installation.

And bolted in nice and tight:



Released the locking screw a quarter turn while holding the inlet camshaft so the chain didn't go springing off the sprocket and screwing up the timing:

Lock nut is done up tight now too.

So, at the completion of that, I did some revolutions clockwise and double checked the timing was still good, and it was, so good stuff there.

Next, I did what the manual recommended and turned the knurled nut on the tensioner counter clockwise while turning the crank a bit counter clockwise. I then released the knurled nut, turned the crankshaft clockwise again, and watched the tensioner unwind itself and put tension back on the cam chain again as it's supposed to. Nice.

Well done Pete. You've done all that just like the perfectionist that you are, just like an old pro. You have the exact same cam chain tensioner that is on my 550 and you have covered everything to the letter. (a) turning the engine over a couple of revolutions after releasing the grub screw on the tensioner to recheck timing and that nothing has moved. (b) reversing the knurled knob and the engine to do the test as described in the manual. Everything done by the text book.

Again well done.

[pete]

Well done Pete. You've done all that just like the perfectionist that you are, just like an old pro. You have the exact same cam chain tensioner that is on my 550 and you have covered everything to the letter. (a) turning the engine over a couple of revolutions after releasing the grub screw on the tensioner to recheck timing and that nothing has moved. (b) reversing the knurled knob and the engine to do the test as described in the manual. Everything done by the text book.

Again well done.

Cheers Don, I appreciate the compliment, although I don't know if I'd say perfectionist, I just want to do things the right way so I've got the best chance of it firing up first time and not having issues.

However, my update from tonight may change your view...

Also, did you see my question on the other thread regarding the Yamalube carby cleaner? I'm a little confused about the ratio of cleaner to water...

http://www.thegsresources.com/_forum/showthread.php?t=170181

Anyways, on to tonight's, well... progress for lack of a better term.

So, got a spare 15 minutes to pull the left engine mount off today and drill the hole out ready for the helicoil.



Then I went down tonight hoping to get the helicoil done, left mount on, and measure the valve clearances. Just wasn't meant to be I guess...

Firstly, I started off with the left engine mount, so tapping time:



Helicoil in:



Now, here's where the first problem lay.

You will see that the helicoil projects out of the mount, which seems expected, until you realise that I tapped from the rear of the mount and didn't tap all the way through, so trying to put the bolt in from the front didn't work at all.

Fortunately, the projecting helicoil means I was able to unscrew and remove it then retap the thread all the way through.

I was able then to put the helicoil in from the front properly and the bolt was a good smooth thread in then, nice.

However, when I went to bolt the mount on, I discovered that by torquing up all the other mounts without the front mount on, it had tilted the motor marginally to the left, probably something like 2mm which is barely noticeable until you try and squeeze the left mount between the frame and the engine.

So, instead of doing the smart thing and loosening all the engine mounts and getting the front mount on properly, I did my best to jam it in and do the bolts up.

Apart from this taking about an extra hour, it meant there was too much pressure on a weird angle for the bolt, and the result is:



I also didn't trust the helicoil so I was once again able to use the little bit projecting out the back to unscrew and replace it again.

So, next time I'll loosen all the mounts before attempting the front mount again, although I need to get another bolt first.

Teach me for being impatient... but I'm just so itching to get this done that sometimes it gets the better of me...

Anyways, figured I'd move on to the valve clearances and now I'm just confused.

Starting with the right exhaust, I got the lobe of the camshaft perpendicular to the shim:



Smallest feeler guage I have is 0.04mm and it wouldn't go in between the lobe and shim, so I would say I have pretty much no clearance there.

I had exactly the same result on the right inlet:



No clearance there either.

I was pretty tired by then so I decided to pack it in for the night and I will tackle it again when I'm not so tired, hopefully tomorrow night.

It'll be interesting to see if I get no clearances all 'round, as I expect that means the facing of the valves puts them too close even though he tipped them as well.

[Suzuki_Don]

Hi Pete, I see you don't seem to have any clearance on your shims. When the clearance is less than .04mm the way to check if there is any clearance at all or if the base circle of the lobe is holding the valve open is to try and rotate the bucket using the notch cut into same. If the bucket rotates then there is some clearance there and one shim smaller will do the trick. If it doesn't rotate then you likely will need at least two size thinner shims.

When you have checked this out tonight repost and tell us the clearances you come up with, if you can rotate the buckets when the lobe is on the base circle, and the size shims that are currently in the buckets for the different valves. And what other shims you have as spares to swap with the ones currently in the engine.

Do you have spare shims?

[Suzuki_Don]

Pete, it's an old trick when bolting anything back together that has a number of bolts, studs, screws, etc. to do them all up loosely and thread them up to within a thread or two of being fully home and this enables you to wiggle the unit around so all bolts can be screwed into their respective threads and when all the bolts are threaded up do them up progressively which helps pull the motor in your case into alignment correctly. It looks like one of your engine mount plates is slightly bent or frame is out of alignment in some way. More likely the mounting plate though.

When the engine is bolted up firmly, just run a straight edge along both of the sprockets to make sure they are in line before you go any further. These being in line is a must. I don't think you will have a problem here, but best to check at this stage of reassembly than to have to pull things down later, if you find the rear chain does not fit properly. Should only take 5 mins. to check anyway.

[pete]

Hi Pete, I see you don't seem to have any clearance on your shims. When the clearance is less than .04mm the way to check if there is any clearance at all or if the base circle of the lobe is holding the valve open is to try and rotate the bucket using the notch cut into same. If the bucket rotates then there is some clearance there and one shim smaller will do the trick. If it doesn't rotate then you likely will need at least two size thinner shims.

When you have checked this out tonight repost and tell us the clearances you come up with, if you can rotate the buckets when the lobe is on the base circle, and the size shims that are currently in the buckets for the different valves. And what other shims you have as spares to swap with the ones currently in the engine.

Do you have spare shims?

Cheers Don, that all makes sense to me. The buckets rotated real easy before I put the camshafts in so if there's any clearance then they should still rotate nice and easy. I'll give that a go tonight.

One thing with these is that I took the camshafts and buckets out years ago, so it's always possible I've transposed them left to right, whereas the valves were only taken out recently so I know for a fact I kept them where they belong.

Unfortunately I have no spare shims at the moment, so I expect no matter what I will need to buy one or two so I can swap them out as I go. I don't want to be in the position of needing to rotate a camshaft without a shim in a bucket as I've seen what happens if you do that and I won't do it.

I never even knew I had to do valve adjustments until I'd already taken it off the road years ago and started reading the forums properly, so I have no idea what the clearances were like before disassembly which doesn't help.

I really want to replace the shim that has no markings on it too.

Pete, it's an old trick when bolting anything back together that has a number of bolts, studs, screws, etc. to do them all up loosely and thread them up to within a thread or two of being fully home and this enables you to wiggle the unit around so all bolts can be screwed into their respective threads and when all the bolts are threaded up do them up progressively which helps pull the motor in your case into alignment correctly. It looks like one of your engine mount plates is slightly bent or frame is out of alignment in some way. More likely the mounting plate though.

When the engine is bolted up firmly, just run a straight edge along both of the sprockets to make sure they are in line before you go any further. These being in line is a must. I don't think you will have a problem here, but best to check at this stage of reassembly than to have to pull things down later, if you find the rear chain does not fit properly. Should only take 5 mins. to check anyway.

Yeah, the stupid part about all this is that I know that trick and use it quite often, just not this time...

If I hadn't have stripped that hole initially when being careless with not double checking the torque wrench, then this would not have happened. Instead I've now been careless twice on the same thing and I've ended up in this situation but at least it's not terminal!

Quick edit: Thanks for the tip on checking the sprocket alignment too, hadn't even thought of that. The way the engine was sitting simply makes me think I shouldn't have torqued everything up until the front mount was on as the way it looks to my eye is that the front mount will actually bring it all up and level, but it's good to know there's a technique to check.

[Suzuki_Don]

Unfortunately I have no spare shims at the moment, so I expect no matter what I will need to buy one or two so I can swap them out as I go. I don't want to be in the position of needing to rotate a camshaft without a shim in a bucket as I've seen what happens if you do that and I won't do it.

I really want to replace the shim that has no markings on it too.

If you have a vernier caliper you can measure the thickness of the shim with no markings, or a micrometer would do.

Let me know what shim sizes you are using at present and I can check if I have any thinner ones in the spare ones I have.

[pete]

If you have a vernier caliper you can measure the thickness of the shim with no markings, or a micrometer would do.

Let me know what shim sizes you are using at present and I can check if I have any thinner ones in the spare ones I have.

I tried with the micrometer I got for Christmas, but unfortunately the instructions don't match the device, so I still need to work that out.

I did record the reading on the micrometer so once i work out how the scales work i'll know the size of the shim.

I was planning on using the feeler guages to work out the scale as I'm very confused about it.

I'll let you know how things go...

[Suzuki_Don]

A quick tutorial

Pete, a quick tutorial on "How to Read a Micrometer" by Don Clifton.




In the above diagram the marks above the horizontal line are full millimeters, the marks below the horizontal line are 1/2 millimeters. You will see that in this measurement there are 2 full millimeters and it has not yet got to the next half mm. So the reading is 2mm + the reading that is on the radial part of the micrometer. So in this case it is 2mm + .31mm which equates to 2.31mm or this shim size is 230. As I could not hold the micrometer and camera at the same time it loosened a bit and read 2.31mm instead of 2.30mm.

Hope this helps. But your micrometer could be different. Different scale. Mine is measured in 1/2mm. It will be indicated on the body of the micrometer somewhere.


This is my scale as follows; 0-25mm (that is the total range of the micrometer) and 0.01mm (which is the size of each increment on the radial scale) One total revolution on the radial scale = 0.5mm which is equivalent to one segment on the lower scale on the main body of the micrometer.






.

[pete]

Cheers for the quick tutorial Don, much appreciated. As per my PM I did work it out though... it's an imperial micrometer with metric instructions





Anyway, 102 on the micrometer = .102 inches and 2.60mm which is what I had figured it was compared to how the other 2.60 registered in the micrometer.

Also explains why I saw 39 with the 1mm feeler guage... .039 inches = 1mm or close enough to it.



Now, as to what shims and clearances I have, here's the list:

Left inlet: 2.60mm with what feels like some contact, bucket rotates but with difficulty.

Left exhaust: Exactly the same as the left inlet, this is the unmarked shim that I now know is 2.60mm.

Right inlet: 2.65mm, no contact, but less than 0.04mm clearance.

Right exhaust: 2.55mm and there is definitely contact with the shim, the bucket doesn't rotate very easily.

I'm pretty confident I could safely go 2.55mm for the left side, but I'm not sure if a 2.50mm would be small enough for the right exhaust or if I would need a 2.45mm, although my gut feeling says 2.50mm would be ok.

So, I believe I would need to procure (swap, buy, loan, whatever):

1 x 2.50mm - right exhaust
1 x 2.55mm - left inlet or exhaust

I can then move the right exhaust (2.55mm) to the left inlet or exhaust and the left inlet or exhaust (2.60mm) to the right inlet.

Does all that make sense and seem to be right? Some of it is guesswork unfortunately, but I don't know how else to work it out.

And just for a little side topic...

This is my Honda Civic that's been sitting at my grandparent's place at Yeronga since about 2001:



That's its roof poking up out of the water:



At least it only wet the garage and under the house which is dirt anyway:



Fortunately, that's the only impact anyone in my family had from the flood, unfortunately some of the neighbours at Yeronga weren't so lucky, and there's a guy at work who lives near there who just raised his house last year and just finished renovating downstairs a few weeks ago and he got about half a metre of water through downstairs the poor bugger.

And I must mention one of my team members who's flat he's currently renting has no walls and may not have a floor real soon if the building inspectors say it's no good, but at least he got a car load of all his important stuff out before it got wet.

[pete]

I figured I'd skip trying to do anything with the engine mount tonight and instead I'll wait for some time with the house mate so we can do it together a little more cautiously and avoid any more stripped threads. I also still need to get a new bolt.

So, decided to get a start on the carbies now that I have some carby cleaner dip, although I still need a sauce pan and some spray carby cleaner.

So, here's how they started off:





Had a good spray of WD over all the screws and fasteners to try to make them a bit easier to get out:



And first thing off was the choke lever and choke shaft:



Notice my dead shells of former little friends between the carbies there. Gotta love daddy long legs and how they seem to get everywhere...

[pete]

Top bracket off:



Bottom bracket coming off:



And as instructed by the Clymer, taking special note of the throttle connection:



And they're split:



Float bowl drain plug out, and not looking terribly clean inside:

[pete]

Float chamber needs some cleaning up for sure, as do the floats themselves:



And I stopped there because I remember getting some advice from Sharpy to be real careful with the float pin and posts, so I stopped until I could go and read what he said again.

So, that's it for tonight, but I do feel somewhat relieved that I know what's happening with the shims. Thanks again Don!

Definitely won't be working on it tomorrow night or Wednesday as we'll be picking my wife's new (to us) car up tomorrow after work, and then I expect Wednesday will be learn all the buttons and knobs on it day...

[pete]

Oh, and Wednesday being Australia Day means it's also the one year anniversary of me not smoking, so I believe a beer or three would be in order for that little celebration