GS500 running on one cyl.

[Nudie]

My flat mate just bought a GS500 on fleabay. Seller describes it as basicly good nick, but only running on one cylinder. Gunna pick it up for him this week and get stuck into it.
So the question is, where should I start looking for the cause? I'm guessing plugs, coils etc. But has anyone else been thru this before?
I've told him to get us a workshop manual to make it a bit easier.

[Large]

When did you move in with Clint?

[Ross_247]

I had a mate who bought one on fleabay actually same scenario, Luckily for him a new spark plug and coil was all it was so I rekon ya in the rite area, before ya really have to open her up : ) they are a prety bullet proof engine so id say its only something simple like that big fella

[Hagarr]

Four stroke cycle is essentially like this

1.Suck - check intake filter etc is clean and no blockages,water
2.Squeeze- Have compression. will fire
3.bang- have fuel and spark. will fire
4.blow- check exhaust when cranking if no smoke no fuel, smoke fuel but no compression

Its just a matter of process of elimination

Good Luck!

[Nudie]

Cheers all.
Will let youse know when I get me dirty mits on it. (fucking around with someone elses bike. A bit like having a mistress innit!)

[fimpBIKES]

i had a mate watching that one too

it'll be an easy-fix, how much on such a simply designed bike could go wrong?!?!

ps- if you grab a manual off the net i think they normally have solutions to common faults

[Iceman]

As previously mentioned, try plugs first. I have had a lot of trouble with plugs since we injected mine.

[stu]

Had one of these years ago. As mentioned, plugs first and all that stuff if it is indeed only running on one cylinder. On the other hand if it is just running like shit and all else seems ok see if he knows when the valve clearances were last done as they can suffer a bit from that if it has been a while. If memory serves me correctly Suzuki stipulate valve clearances at either every 5 or 10,000, can't remember which, but I recall it being a way shorter interval than the normal 24,000 or so.

[Nudie]

Apparently it's only got 19,000kms on it, so I cant imagine it would be a major drama.

[ralph]

gsresources.com

[ralph]

thegsresources.com and do the valve clearences anyway

[stu]

quote:Originally posted by Nudie

Apparently it's only got 19,000kms on it, so I cant imagine it would be a major drama.


Double checked my memory and the valve clearance interval for the GS is indeed every 5000km. Just about time for the 4th time around then. ;)
May wind up a drama if they haven't been done.

[ralph]

I have a few different shim sizes
There are some other blokes on this site who will have shims and
there is a bloke in Croydon vic who whips them up for 10 bucks a pop
I have his details in the shed

[Nudie]

Upon inspection, it has no spark on the right cyl. Coils test OK, wiring is good all the way back to the ignitor (not CDI).
W/sop manual shows how to test the coils, but says the only way to test the ignitor is by giving it to a Zook dealer.
Anyone know where to source an ignitor without paying the earth?

[livewire]

Can you swap pickups and see if dead spark swaps as well?

[Nudie]

Yeh thats the next step I guess. Extra Dry is in the way at the mo'
weell see tomorow

[Nudie]

Well i've exhausted my bag of tricks and it's still running on one. I tested the coils, wiring continuity and swapped plugs. Still no good. Mate bought another Ignitor and had it running, said it sounded good, but when I got home and earthed the plugs on the head it's still only sparking on the left cyl. I've swapped the pick up on the coils and the right coil sparks, but only with the left feed to it (so both coils are fine). Bridged the wiring direct from Ignitor to coils, no good.
Anyone know what a dealer would charge to test the Ignitors? Cause it seems odd that both of them dont have spark on the right cyl. I've proved plugs, both coils and wiring are all good, so it only leaves Ignitor untested.
Oh BTW the Ignitor he got from a wrecker on Find-a-part.

[Nudie]

OK then, upon further investigation, it would seem that there is such a thing as a "Signal Generator" involved here as well. The manual says to use a "Pocket tester" (read, genuine overpriced Suzuki tool with it's own part number) to test the signal generator, and what the resistance should be. So I used my ohmmeter and can only get a reading on one side. Tomorrow I shall uncover the whereabouts of this Signal Generator and delve deeper!

Stay tuned! (or go about your business and i'll STFU)

[grindella]

signal generator, known as pick ups are located under one of the lower covers, (I think the left one)

[fimpBIKES]

right one on most suzukis i think, stator on the left

sounds like it would be worth a shot, keep us posted nude-man

[Nudie]

Yeh RHS on this one. Will check wiring continuity from SG to plug on ignitor, if this is all good, it's gotta be the SG. There's nothing else then that I haven't checked!
But, I gotta go away to work for a while. Should be back monday or tuesday.