Mechanical/restoration supervision sought

[Ixion]

Yeah. Even or odd. But the Japs will often put a one size smaller head on a bolt, especially on frame trim stuff. Aesthics. Then you need the uneven sizes.

[psyguy]

Most likely an ISO or European set....14mm is not a common size.When anyone who works exclusively on Japanese bikes or cars works on anything non Japanese they cry foul with the oddball 11mm,13mm,15mm,18mm sizes.The ISO head sizes equate to the Imperial head sizes - 7/16 became 11mm,1/2 became 13mm....in the 3/8 bolt sizes which had 9/16 heads,ISO seems to prefer 15mm or 17mm.The Japanese don't do ISO....they have their own Imperialism.Work on Euro stuff long enough and you curse the bloody Japs instead.

thanks for this motu. i often wondered about different head sizes and i sometimes find that the imperial spanners may fit better on a particular suposedly metric size head (than the metric spanner)

[terbang]

Ahh a fellow GS nut. I've owned a whole bunch of them, mainly 1100's. Have rebuilt various GS (X) engines and gearboxes over the years and there are no real traps. Yours is the 8 valve version with the shaft drive. I see you are going to refurbish the casings that were origionally painted by Suzuki. You can't get the paint anymore as you would expect and a lot of people use the VHT or similar in a can product that you can get from repco. What I have done with the casings, cylinder block and head is just sand blast them (I have a small home jobby), get a product from Croda Lusteroid (Christchurch) called Caprithane 'Metallic fine' which is the base metallic paint before any colour. They paint aircraft cowlings with it. Its a 2 pack epoxy type paint that will poison you if yer not careful and you will need to apply an etch primer. It leaves a finish that looks like aluminium a bit glossed up. I have a bike that has done 80,000 kays on that paint and it has few chips, no stains and cleans up real nice.
When you assemble the engine replace the camchain, camchain tensioner blocks and Intake boots that are still available. Have a close look at 5th gear as they are often worn at a lower mileage than you would expect and the clutch baskets are a bit of an achilles heel on GSes as well. The crank is a roller assembly (I think on that model). They are like rocking horse shit and real expensive to rebuild so make sure it is well inhibited when apart. A simple runout check is all you can do there. I have used Wiseco pistons in the past and they have been good though choose your machiist well as they won't take kindly to a slightly offset bore (no engine does really). They are a great project engine and you will also have heaps of fun riding it when it's done. I'm working on converting an 82 1100 to fuel injection at the moment probably will adapt an R1 body with US scourced electronics.
Have Fun and If you need any help give us a yell.

Here is a picky of the finish

[terbang]

Most likely an ISO or European set....14mm is not a common size.When anyone who works exclusively on Japanese bikes or cars works on anything non Japanese they cry foul with the oddball 11mm,13mm,15mm,18mm sizes.The ISO head sizes equate to the Imperial head sizes - 7/16 became 11mm,1/2 became 13mm....in the 3/8 bolt sizes which had 9/16 heads,ISO seems to prefer 15mm or 17mm.The Japanese don't do ISO....they have their own Imperialism.Work on Euro stuff long enough and you curse the bloody Japs instead.

Man,you are really moving along there,that's about 3 years progress for me!

7/16 is not exactly 11mm and 1/2 is slightly smaller than 13mm (though 1/4 whitworth is 13mm), 9/16 is a tight 14mm and 11/16 is close to 17mm (but not the same) and 7/8 is 22 mm. Just buy a good set of metric spanners and sockets. The most commonly used ones on the GS series is 8mm, 10mm, 12mm, 14mm, 17mm, 19mm, 22mm and 24mm. The bolts on the starter cover are an odd size (7mm I think) that I usually have to use my metric adjustable on.

[Motu]

I never said they were the same size,it's just that a 1/4in bolt with a 7/16 head is very close to a 6mm bolt with an 11mm head.To me it's a visual thing - you work on nuts and bolts all day,and you just look at it and say I need a 17mm or 19mm for that.A 1/2in,13mm and 1/4 Whitworth are very close in size,but I never mistake what spanner will fit.Like the change from Whitworth to SAE,the change to ISO was to keep things ''sorta'' the same.

[Laava]

That's a mighty fine pile o' bits there pal! Good luck with that! I assume you were going to do the vapour blast and leave it at that, I did that on an old Laverda and it looked good and was easy to clean as the surface was quite smooth. The paint system that Terbang is on about sounds good too. I assume you'll be doing everything on the bike? You might need to move it into the lounge! Is all the wiring OK? That for me was the worst bit. Don't rush it and don't add up how much it costs or you'll never finish it. Cheers

[psyguy]

Ahh a fellow GS nut...

cheers terbang!
a really useful reading and yes i might need to give you a yell further down the track as, as i said, this is my first ever project
nice finish on that bike

[psyguy]

That's a mighty fine pile o' bits there pal!...

yup, i've heard that vapour blasting gives a real fine long lasting finish (and i dont mind a bit of oxidation as long as the surfaces wash ok)
i started the project with the engine as it needed attention anyway, but yes i'll most probably continue the restoration, finances permitting
i don't know that much about electrics, so all i can say for now is that everything works fine. or does it?!
cheers

[psyguy]

well, i've been polishing bolts. lotsa bolts... check out the before/after picky

anyhow, more importantly, i've checked internal componets for wear/damage and measured what i could

the good news is that they are all within factory margins and some are in remarkably good condition (e.g. the crankshaft and the gearbox parts, the camchain, etc)
however, some are at the botom end of those margins
this goes for:

• camshaft lobe heights,
• camshaft diameter,
• exhaust valves stems (a bit of play in fully open position)
• valve springs

now, could someone possibly give me an educated guess on how much more service i can expect from these components before they start showing more obvious signs of wear?

cheers

[Ixion]

Well, valve springs are cheap(ish) and weak ones can lead to Mr Valve thumping Mr Piston, which is rather nasty. So if there is any doubt...

I assume by exhaust valve stems you mean stem to guide clearance. Not such an issue IMHO, if they are in spec worst likely is a bit of oil burning and a very slight power loss.

Crankshaft diameter. Hm. That's a tricky one. Worn crank = low oil pressure = big bang at high revs. And a worn crank will wear faster than a good one. IS it scored at all? A regrind and new shells is not a VERY dear matter. If you can get oversize shells (I'm assuming it's a shell big end - if its rollers thats another matter)

Camshaft lobe heights? Personally I wouldn't worry if they are still in spec , even if only just. So long as they are not scored. They may reduce peak power very slightly, but won't wear any faster (until they wear right through the hardening). And won't (usually) cause any damage. And it is a relatively easy job to replace them in years to come if needed, you don't have to strip the whole motor. And new camshafts won't be cheap.

Very much a personal opinion thing of course, others may differ. And it depends what you want and what you intend to do with the bike. If you want it brought back to new condition, then clearly anything out of spec or just in should be replaced. And if you were goign to race it, that would be another matter again.

[jonbuoy]

well, i've been polishing bolts. lotsa bolts... check out the before/after picky

anyhow, more importantly, i've checked internal componets for wear/damage and measured what i could

the good news is that they are all within factory margins and some are in remarkably good condition (e.g. the crankshaft and the gearbox parts, the camchain, etc)
however, some are at the botom end of those margins
this goes for:

• camshaft lobe heights,
• shaft diameter,
• exhaust valves stems (a bit of play in fully open position)
• valve springs

now, could someone possibly give me an educated guess on how much more service i can expect from these components before they start showing more obvious signs of wear?

cheers

My advice FWIT (not much!) lobe heights wouldn't be much of an issue for me as long as long as its even wear and not badley pitted - I guess it means the valves wouldn't be opening quite as much so slightly de-tuned engine? Valve stems would mean a bit more oil burning, and valve springs I guess would mean you might want to lower your redline. I guess it depends on if you want to ride it like its new or ride it like a 20Y/O machine. Good luck with the build. Some of the real mechanics might be able to tell more from pictures of the wear on these bits.

Cheers.

[psyguy]

thanks guys
i wasn't too clear i guess, the shaft diameters in question are on the camshafts (at the place where they're bolted down)
the crankshaft is quite fine

if i'm reading this correctly, i should be fine for a while as i intend to ride the bike in a moderate fashion, like a cruiser. well, mainly...
and i can attend to valves, springs and possibly camshafts later on

[Ixion]

Oh, camshaft journals. No I definately wouldn't worry about them. I would suggest considering replacing those springs though. They're not usually that dear, and even if you don't intend to ride it hard, one can never discount the possibility of high revs on a four cylinder. A missed gear change if nothing else.And they'll get worse the worse they get - ie the weaker they are the quicker they get weaker still, so the wear accelerates.

[peasea]

You're not wrong about missed shifts. With race engines I have built, with valve springs right on the limit, one missed gear or the vehicle getting airborne at full throttle usually nails the whole set. Do them now while you're in there.

Just be methodical, keep things clean and don't force anything. Projects are good fun, better than any TV show.

I also use nut fuckers but usually only on domestic plumbing; I don't think they have any place on an engine, the nick-name came about for a reason.

[psyguy]

no more nut fuckers, i promise
thanks for the comments peasea