Steve Saunders Goldwing Forums banner

Status
Not open for further replies.
1 - 6 of 6 Posts

·
Premium Member
Joined
·
118 Posts
Discussion Starter #1
imported post

hey how is everyone doing i need some help and advice on my 86 gl1200i it is back fireing some usually happens after i have rode 15 to 20 miles then shut it off for a while usually 20minuate or so then when i start it up it will back fire i use 93 octaine fuel and keep the plugs and filters changed and set at least every 2500 miles any help will be really appreciated thanks dave t
 

·
Premium Member
Joined
·
1,207 Posts
imported post

Sounds like a carb is leaking a bit into a hot cylinder, also your bike is actually designed for lower octane fuels, good ole 87 is all ya need, save your cash :cheeky1:
 

·
Premium Member
Joined
·
118 Posts
Discussion Starter #3
imported post

Thanks for the advice wildcat, ill check the carbs and see what i can find there , as for the fuel i sure could of saved a bunch of cash over the last 3 years but that is ok now ill save it . i just always ran everything on 93 octaine , and i did really know that and saw that in the owners manuel just didnt pay attention to it old habbits i guess. just like the way i put it on this post it is a gl1200I not a 1220 thanks again dave t
 

·
Premium Member
Joined
·
578 Posts
imported post

Check over your exhaust, a small hole or a failed joint will cause a backfire on the overrun when the pipes are hot.
 

·
Premium Member
Joined
·
2,491 Posts
imported post

dave t. wrote:
hey how is everyone doing i need some help and advice on my 86 gl1200i it is back fireing some usually happens after i have rode 15 to 20 miles then shut it off for a while usually 20minuate or so then when i start it up it will back fire i use 93 octaine fuel and keep the plugs and filters changed and set at least every 2500 miles any help will be really appreciated thanks dave t
Dave your Wing has a (lost spark) type ignition.. What that means is it sparks each cylinder at both TDC compression & TDC exhaust. If there is an ignitable (burnable) mixture in a cylinder at hot cranking it will fire that off & it will pop back through the open exhaust valve &backfire in the exhaust. Some seem to do it more than others, if the engine is stopped with an open intake & exhaust valve on the same cylinder the hot muffler & convection flow will pull fuel & air into that cylinder & leave a stoichiometric mixture in that cylinder. A slightly internally leaking carb can also allow fuel into a cylinder that will ignite on hot re-cranking, a small hole or leak in the exhaust can also allow a backfire at start-up..

The best cure is to add a single fire ignition but that isn't available for the 4 cylinder Wing.. Another cure is to add a 2 revolution cranking delay to the spark system so it cranks over twice before sparking any cylinder (not practical to do).. You might try turning the R/H handlebar kill switch to off before cranking, then once it starts cranking turn the switch on.. If that stops the backfiring then you will either have to live with the backfiring or start it like that, or play with the throttle & choke to find a place it will start without the backfiring..

Twisty
 

·
Senior Guru
Joined
·
2,234 Posts
imported post

twisty wrote:
dave t. wrote:
hey how is everyone doing i need some help and advice on my 86 gl1200i it is back fireing some usually happens after i have rode 15 to 20 miles then shut it off for a while usually 20minuate or so then when i start it up it will back fire i use 93 octaine fuel and keep the plugs and filters changed and set at least every 2500 miles any help will be really appreciated thanks dave t
Dave your Wing has a (lost spark) type ignition.. What that means is it sparks each cylinder at both TDC compression & TDC exhaust. If there is an ignitable (burnable) mixture in a cylinder at hot cranking it will fire that off & it will pop back through the open exhaust valve &backfire in the exhaust. Some seem to do it more than others, if the engine is stopped with an open intake & exhaust valve on the same cylinder the hot muffler & convection flow will pull fuel & air into that cylinder & leave a stoichiometric mixture in that cylinder. A slightly internally leaking carb can also allow fuel into a cylinder that will ignite on hot re-cranking, a small hole or leak in the exhaust can also allow a backfire at start-up..

The best cure is to add a single fire ignition but that isn't available for the 4 cylinder Wing.. Another cure is to add a 2 revolution cranking delay to the spark system so it cranks over twice before sparking any cylinder (not practical to do).. You might try turning the R/H handlebar kill switch to off before cranking, then once it starts cranking turn the switch on.. If that stops the backfiring then you will either have to live with the backfiring or start it like that, or play with the throttle & choke to find a place it will start without the backfiring..

Twisty

Actually Twisty, I should have a single fire ignition systemcompleted for the GL1200 sometime this winter.It's something that I've had toconceive to allow me tooperate my home built fuel injection system on my Wing. Once completed I will be able to adjust fuel mixture and ignition timingvia buttons on anelectronic display panel on the dash. It's been a long time coming, but now I've finally got allthe electronics built and working and the final step is integrating the finished ignition system.

Vic
 
1 - 6 of 6 Posts
Status
Not open for further replies.
Top