GS500 only one cylinder

Pete125 · Derestricted Danger Joined: 15 Aug 2006 Karma :

Hi i was wondering if anyone here could help me out with a problem with my gs500 project.

The problem im having is that its only firing on one cylinder i have swapped plugs around to see if it was the plugs at fault but no joy, the same cylinder wont fire. Im sure petrol is getting through as the plug gets wet ect.

Im guessing the next thing to try would be to try swapping the coils over to see if its the coils at fault.

Apart from that im at a loss at what it could be any help would be great thanks

almost forgot its a pain to start aswell but i have found that taking the plug out of the problem cylinder and hitting the start button seems to help getting it to fire up.

Casper · World Chat Champion Joined: 12 Jul 2010 Karma :

Does the problem side spark when plug is out and sitting on the block? Also you could have a stuck valve.

Pete125 · Derestricted Danger Joined: 15 Aug 2006 Karma :

Thanks for the quick reply,

Yes but its not what i would call a great spark tho, also its not very frequent like the other side.

Stuck valve hope not was really hoping to not have to take the engine out Smile

Casper · World Chat Champion Joined: 12 Jul 2010 Karma :

Shitty spark. Could be the igniter box is duff or pickup set wrong. Is this points or electronic on this bike. Just trace yoursel backwards checking all conections. If it has two coils try and swap them over to see if problem shifts, if it does you have a fooked coil. How is the HT lead, not old and split is it. Try swaping them as well. If it was running fine before it was taken apart i am sure it will be something stupid. Also look at the join where the HT goes into coil as if water had got in there then this can happen. Also HT into spark plug cap, cut a few mm here and screw back in to make sure you have a good connection.

Pete125 · Derestricted Danger Joined: 15 Aug 2006 Karma :

Hi yeah its electric going to try swapping the coils to see if i can get it to fire on the problem side.

Hopefully this will get it going as i seem to have lost my multimeter duh.

Casper · World Chat Champion Joined: 12 Jul 2010 Karma :

Pete125 · Derestricted Danger Joined: 15 Aug 2006 Karma :

Hmm swapping coils didnt seem to get that cylinder to fire up either,

But i did notice that after cleaning the plug putting on stove ect, and trying again that its not getting wet from fuel ect so i drained the carbs to see if they had fuel, they did. could the carbs be blocked somewhere stopping the fuel air getting to the combustion camber if the float is filling up fine ?

I've never stripped carbs before so not too sure any advice please

Thanks.