1981 GS450E Rebuild

[pete]

Pete you need to swap the two exhaust valve shims and that should make the right cylinder correct or closer anyway. That means it would be coming down from 2.65 to 2.55 instead of 2.60 which is an extra .05mm clearance. After this swap is done check the clearance with the feeler gauge to make sure it is OK. Then you will need to order a 2.50 shim for the left exhaust valve.

This should make them all OK, but there's no guarantee when doing the valves after a rebuild. Unless you have an ultra thin shim to put in to take measurements with, then you have to pretty much experiment because if a valve is a bit tight you don't know whether you need to go down one size or two to gain the correct clearance. I have a 2.25 shim I insert and get the measurement with the feelers and from that I can work out what size shim I need for the respective valve. I also have about 30 shims counting the ones in the engine currently so I have a good selection for my own use. I was lucky in that I picked up a couple of cylinder heads on the cheap and they all had shims in them.

Makes perfect sense thanks Don and is what I was thinking about last night and earlier this morning.

I did order the extra 2.45mm shim which is currently sitting on the work bench so I can use that to work out what I need hopefully.

[pete]

Rightio, back at it tonight, and I now have three out of four valves done.

I popped the spare 2.45mm shim in the left exhaust, and still less than 0.04mm clearance. I just realised I didn't check if the bucket rotates easily or not, so not sure if I should go down 1 or 2 sizes.

Anyway, I popped the unmarked 2.60mm shim into the left exhaust for the time being and tried the 2.45mm shim in the right exhaust. 0.06mm clearance! Yay!

I believe I should get myself both a 2.40mm and 2.35mm for the left exhaust to allow for either one or two sizes down.

Here's a gratuitous pic with no merit at all as to what was done tonight:



So, after my 50% success rate there, I decided to clean up and mount the top cam chain guide in the valve cover.

Dirty:



No guide:



Clean:



Guide:



I used thread locker on the screws just in case. Don't want them coming out and letting the guide float around in there!

And back onto the carbs again.

Firstly, had Asia Canteen for dinner on Saturday night and whacked the containers through the dishwasher because I have a use for them:



House mate also managed to score me a nice sized sauce pan for $5 as I've had no luck finding cheapies:



So, this is where they were left:



Needle valve assembly removed:



Quite disgusting in there really... but what can I expect from 30 year old carbs that have been sitting idle for 9 years?

[pete]

I wasn't able to get the needle jet to move at this point, so I left it and moved on for the moment after squirting it liberally with some WD.

Onto the diaphragm cover and diaphragm:



Not as bad as I thought in there, but still not nice:



Onto the choke plunger:



And this is for my reference of how the spring hooks onto the left carby:



Assembly off, and another pair of gaskets to obtain:



At this point I sorta stopped taking pic's so much because Flaming Chainsaws' guide really covers this off and I was having trouble getting the camera to focus properly in the crap light I have to deal with in the garage.

I did take note of how many turns out the pilot air screws were, which was 2 1/4 turns for the left carb and 2 turns for the right carb.

I removed those, then removed the pilot jet and main jet from the float chambers.

I then removed the boots from the airbox that were still attached as well, which left them quite messy indeed:

[pete]

Ugly:



And that's where they sit, so close to being ready for cleaning:



So, I need to run through the cleaning and inspection part of the Clymer and revisit the carb cleaning guides around the place including FC's to make sure I've got everything covered off.

I need to get the needle jets out too as they're still stuck quite firmly in there at the moment.

I also need to start tracking down some nice stainless allen head bolts for the carbs and think about if I'm going to paint or polish them also.

[Charlie G]

Pete,

Thanks for the carb pictures. I need to do this to my 450 this year, as I pretty sure I have some air leaks somewhere in the system. Where does FC have his carb rebuild listed. Is it in his 450l rebuild thread? I'll have to poke around. What is all that amber colored junk on the intake side of the carbs? Looks nasty!

cg

[pete]

No probs at all Charlie, although they're definitely not in the same league as what FC has in his guide, which is on BassCliff's site by the way:

http://members.dslextreme.com/users/cbsaunders/gs/gs450_carb_cleaning_guide.pdf

Enjoy

As to what the amber crap is, your guess is as good as mine! Another present from the PO is what I'm thinking at the moment to match up with the unlabelled shim...

[Charlie G]

No probs at all Charlie, although they're definitely not in the same league as what FC has in his guide, which is on BassCliff's site by the way:

http://members.dslextreme.com/users/cbsaunders/gs/gs450_carb_cleaning_guide.pdf

Enjoy

As to what the amber crap is, your guess is as good as mine! Another present from the PO is what I'm thinking at the moment to match up with the unlabelled shim...

Thanks for the link Pete. FC did a nice job on the tutorial. I'll have to tell him so.

cg

[pete]

He did indeed! The only thing I noticed was that on his choke lever assembly, you'll see the two screws are reversed as opposed to where they should be, which I verified on the fiche.

They should be like this with the philips on the pivot and the flat head on the slider:



I must PM FC now actually and let him know in case he put them back together the same way...

[pete]

Rightio... carbs are completely disassembled ready for cleaning and I just filled out the online quote form for a 2.35mm and 2.40mm shim as I didn't get a chance to do that today. If it's express post like last time, they'll be here on Wednesday.

So, after a night soaking with the WD, time to get the needle jets out.

Right:



Left:



I was able to get a good firm grip with a large pair of pliers and gently twist them left and right and gradually pull them free. The large pliers allowed me lots of purchase on lots of surface area on the needle jet with less chance of slipping off and potentially damaging them.

I found the easiest way to get the overflow hoses off was to wiggle a flat blade in between the carb housing and the end of the hose and use a twisting action to push it off. They both came off no dramas like this:



So that's that, everything's off that comes off to clean the carbies, so the left one looks like this:

[pete]

And the right one looks like this:





Both aren't as bad as I thought they'd be inside, however I know that there will be old gummed up fuel in those pasages that will defy every attempt to run the bike smoothly without a proper clean.

I still have no idea what that grunge is on the intake side, but since I took the airbox boots off last night, it's really dried out now and nowhere near as sticky.

I'm hoping to get time on Saturday to do the clean, but I'll just have to wait and see what happens.

Next up, I finally have the chance to start breaking into the excellent Robert Barr's O ring kit!

I'm still impressed by the effort he has put into this. He not only has tips on how to install and not lose the little O rings, but he also has a reminder in with the stainless bolts to use anti seize.



So, one pair of feral intake boots for the head:



Left one cleaned up, and the broken brittle supposed O ring that was there which snapped like a twig during removal:

[pete]

And both cleaned up with nice new supple O rings ready to roll:



Installed with anti seize on the stainless allen bolts and I have just sat the intake port screws in so I don't lose them:



So there she sits.

Once I finish the valves, the valve cover and valve cover breather can go on, so I'd probably best clean up the gasket surfaces on them next and get the oil separators back in.

I can give the end caps a once over with mothers and screw them on also.

I should also be able to get the breather cover onto the valve cover too.

One other electrical thing I need to do aside from make sure the harness is useable for test firing is to test the starter motor before installing it.

Other than that, it's just carb cleaning and assembly and painting the oil filter cover before I can give it it's first kick over.

I can't wait

[SVSooke]

Sweet,you really are moving along.

[pete]

At the moment, I'm just trying to get one bit at a time done as I get time at night. It's a little frustrating that I can't get the carbs cleaned like that though, there'll be too much noise running the air compressor.

Overall though, I'm real happy with the progress so far... I do see yours is moving along slowly too though, and I still say yours will be done way ahead of mine

[SVSooke]

Might help if I went out and did some work on it instead of cruising GSR

[pete]

Might help if I went out and did some work on it instead of cruising GSR

Errrr... yeah, that will definitely help move it along