GS850 Kills at random? what to do?

[nisom512]

I have a 81 GS850. it has aftermarket exhaust, and the bottom of the air box is gone. so I read the Jetting link on Bass's site and the PO had already rejetted the bike. but I belive he did to much.

I can get it running for a good couple min and I ride it around my center circle thing at my house. so the fastest I get is maybe 15 but once I get to high(RPM) it starts to slowly bog no matter what I do and it eventually kills. and when I am going slow and have it in first I mean like starting off the line from a stop it chugs a lot. by chugs I mean when you driving a 5spd car and say you are going really slow and you put it in a high gear and try to give it a bunch of gas. the car kinda chuggs.

So I feel there is to much fuel. oh and I also feel this way because the plugs were black but had been in there for several years.

the jet sizes are.
42.5 and 122.5

they were 40 and 115

Thank you
Jake

[chef1366]

Your bike should run with those jets.
Did you clean the carbs?
Adjust the valves?
Check the ignition? This is what it it sounds like to me.

[SqDancerLynn1]

The CV carbs work on vacuum, they need to be spick & span clean....

[skidMarkNZ]

Those jets wont screw you up that much, check your loom is earthed in all places, is she running on all cylinders? sound like what mine does when its only running on two lol...

Easiest way is just feel your headers...

it shouldnt be that bad with those jets though...

But given whats going on with the airbox it wouldnt suprise me if it is too lean... mine was cutting out at 4,000 prm like you say when i put pod filters on although i didn't richen it up that much.

Also try it with fuel tap set to prime, your fuel tap diaphram could be buggered.

There ya go that should keep ya busy for 30 min lol

Let me know how ya go.

Skid.

[nisom512]

Your bike should run with those jets.
Did you clean the carbs?
Adjust the valves?
Check the ignition? This is what it it sounds like to me.

The carbs are spic and span, new intake o-rings, and carb o-rings all from cycleorings.com

Have not done valves yet. I was just hoping it do it with in a week or so.

I dont know what you mean by check the ignition?

Thank you
Jake

[nisom512]

Those jets wont screw you up that much, check your loom is earthed in all places, is she running on all cylinders? sound like what mine does when its only running on two lol...

Easiest way is just feel your headers...

it shouldnt be that bad with those jets though...

But given whats going on with the airbox it wouldnt suprise me if it is too lean... mine was cutting out at 4,000 prm like you say when i put pod filters on although i didn't richen it up that much.

Also try it with fuel tap set to prime, your fuel tap diaphram could be buggered.

There ya go that should keep ya busy for 30 min lol

Let me know how ya go.

Skid.

all are fireing, and the plugs I took out were BLACK so I bought new ones and it ran better.......a lot better.

Jake

[ryonker]

Hi Jake;

I think he means the timing as regards the ignition.

The other issue could be coils. What voltage do you have at the coils?

Week spark equals poor running .

Do you want to chug it up to white bear so we can look at it together?

Rick

[skidMarkNZ]

You may have the good old suzuki alternator melt, not putting out enough grunt for a meaty spark...

I still think the bottom missing off the airbox is just asking for trouble though...

u checked all wire connections? take apart spray with WD40 or similar and put em back together.

[Don-lo]

I think you need a good, sealed airbox. The slides will not lift out of the way without adequate vacuum. The 850s can be very touchy about this.

[nisom512]

Hi Jake;

I think he means the timing as regards the ignition.

The other issue could be coils. What voltage do you have at the coils?

Week spark equals poor running .

Do you want to chug it up to white bear so we can look at it together?

Rick

I like your idea Rick I would love to.....but no truck+being at school= no time for bikes

it has new coils from the PO and new R/R.

I will do a valve adjustment on sunday(becoming my bike days it seems like) and see what happens but if I get nothing.....and I will try to do a coil relay mod to but i dont know I havent really looked at the new coils to see what they look like.

[nisom512]

just a quick update. so I found the bottom part of my air box yesterday when a buddy drove me home so I could get my bike and threw it on quick now im really excited. I just hope my jetting is correct on it with the bottom part on.

Jake