Tom's 1999 Suzuki GS500EX

[thomas]

After a second-round of shim-adjustment, with waits for postage time, weather and other stuff, got clearances all within their range, the exhausts at the looser end. Churned over a few times with coils disconnected, no plugs, to get oil pumped up, then with a temporary fuel-supply, so I can access the balance-screw, it fired right up, its usual roar burble and bark, heightened and sounding a treat. No bad sounds, from anywhere, nor 'too damned quiet', just ordinary and cold noises that vanish.

Balance screw hadn't been altered, so was bang on at idle, at set point of 1750 rpm, and higher revs, checked using an indescribable device for balancing twins, which I'll attempt to describe all the same. Consisting of a stationary (due to gravity and equal atmospheric pressure at each end) ball-bearing, and a moving ball-bearing in two loops of parallel clear tubing; if in balance, the moving ball pulsing back and forward from induction vacuum at each carb's port, appears to stand still, in line with the stationary ball-bearing.

Total absence of blue-smoke suggests a combination of pistons/rings/barrels and stem-seals have produced a marked improvement with that. Appears oil-tight too, still, hasn't ever leaked a drop. Compressions read are 135psi equal both cylinders, only 21 above the minimum of 114, better than the 110 (and falling) they were. Which is ok considering the rings, barrels and pistons were used, and complete unknowns. It might improve or worsen with some bedding in. Either way it extends its useful life some way, and with care might do another 70K miles.

Both new plugs sooty from just running the engine setting carbs up etc., which might be unrepresentative of real use, it never got really hot, and had fan blowing through it, weaning it off E5 might be enough, else some adjustment: the Jet Needles can be removed from the top of the installed carbs easily, the circlips moved up to the next notch, lowering the needles -but might be the idle parts, the cold-starts or the floats.

Will put about 50 miles on it mid-week and if it hasn't expired, will again remove and clean sump, oil-strainer, and change oil/oil-filter once more (some debris must inevitably have got in when struggling removing the old barrels and later), check plugs, check/readjust the valve clearances again, tweak carbs if necessary.

Visually better too, the fins etc. but that was all secondary to functional overhaul.
Been worth doing, and mildly chuffed with the results.

Some use, then SORNed hibernation with exhaust and air-filter inlet blocked, come winter, awaits it.

[Robsey]

Excellent stuff.
Must be a great feeling when it all goes well and without too much hassle.

My feeling is usually exhausted relief when vehicles eventually let me fix them.
I always seem to make stuff look harder than it should be.

[thomas]

This has been a trial and a terror all the same, it would have been so much easier to scrap it or break it for spares, so much easier to have found some replacement, likely another one of these, in far better condition, or scratch the trail-bike itch, for a fraction of the parts and (own) labour expended on it. As was the case with the crash-damage from 2020, and the difficulty of finding usable forks (having the best of the poor stanchions I could find hard-chromed), bars, yokes, switchgear, tank(s), plastics, painting and stuff.

Been taking this slowly, unlike with a car, in-use, you can step away from it when things aren't going well or to plan, there's no 'critical-section flag' of something which once started has to be seen through all the way as quickly as possible and without attention to anything else till it's done. No timetable, just as and when you're ready, prepared, tackle the the next little step or task, the best you can.

[thomas]

Finally got this running well and gave it a decent run ... to parts foreign, no less.

After an attempt earlier in the week, aborted due to it running too rich and a bit surge and stall prone - fixed by reverting to the original Suzuki Idle-jets, Main jets, Needle Jets/Emulsion-Tubes and cold-start-plungers. With drain-screws and screws for float-bowls and carb tops also replaced. Kept only the gaskets, diaphragms, o-rings, pilot-screws and float-valve parts from the carb service kits.









Ran like a dream, probably quite lean, got properly hot.
Tiny tweak of idle-volume screws and throttle-stop screw afterwards, and it seems all sorted.

[Robsey]

I see you stopped short of invading those sassenachs.

Shame about the jets and stuff.
All sorted now though.
Looking sweet.

A job well done.

[Willson]

Finally got this running well and gave it a decent run! That's nice to hear!

[thomas]

Cheers Willson.

It's SORNed and mothballed now, till the spring next year. The advantage of air-cooling is you have no freezing up or anti-freeze to worry about.
Battery is indoors, it'll be given an occasional, say fortnightly slow charge.
Compression isn't back as high as I'd have liked. Should have followed advice given to replace the rings with new, and have the bores honed.

With the bike getting a a good bit of attention this year, next year it'll get very little, easy stuff: oil and filter, plus front brake master-cylinder seals and f + r brake hoses renewed.

After anything the Cavalier might need is sorted. Wheels and embellishers want powder-coating, wheel centre-badges are in poor nick.