GS850 Hesitates-Stalls

[Anonymous]

Today I changed the air filter and put in a K&N filter and changed the oil. I also sprayed the carbs with some carb cleaner with it running about 2500rpm. Now the fun begins, I replaced the foam side panels and put a new strip on top of filter also cleaned out the whole air box, Had a lot of crappy foam from filter.

The bike ran perfectly fine before this, Although the plugs were black( due to air filter?). Now it wont go down the road without playing with the throttle and won't go above 5000 or 6000. Plus it stalls. Acts like it's starving for fuel.

I also can feel it trying to backfire on top portion of carbs. If you let it set for a while it act ok untill you give a lot of throttle.

Any suggestion would be helpful.

[Anonymous]

Here's a update. Worked on bike most of the day pulled carb bowls and cleaned some crud out not much in them. Pulled top off carbs and inspected diaphragm for any tears or holes none. Sprayed out the main jet and air jet. Caps were still on the idle mixture screws so we took them off, #2 was fully closed and #3 was also, backed out 2 turns. Could not fully remove #3 or #4, project for this winter.

Also put a new set of plugs( I got the NGK Iridium IX ). Went for a ride now it acted up at 4500rpm but would go higer, Plus it was surging at any set speed. Went back had another cupo of coffee and took air filter out. Checked plugs still black and fluffy< cleaned them up and ran it down the road without filter. Ran like a raped ape!! I had some Uni foam around so I constructed a filter and oiled it with some PJ1. Made the filter with the help of some 3M weatherstrip adhesive will stick to anything and dries quick.

Down the road again and ran great!! When I came back pulled one plug and it was nice an tan, Will pull the others after it cools down.

For some reason the K&N filter was restricting air flow ( the bottom portion is not opened like a foam one is. Sorry for being so long winded but maby this will help someone else.

[bwringer]

The 850 sure is picky about its airbox and air, ain't it?

Too bad you spent all that dough on the useless K&N. Oh well. Uni makes a nice foam replacement for the OEM foam filter.

Thanks for the info!

[opiewontaylor]

That is truly strange, because a K&N should be less restrictive under any condition, even without the bottom being opened. Was it over oiled? I would try the K&N one last time, just in case some other restriction was jostled loose while changing filters. (I run a Uni, but only because it's half the price of a K&N).

[opiewontaylor]

The 850 sure is picky about its airbox and air, ain't it?

Too bad you spent all that dough on the useless K&N. Oh well. Uni makes a nice foam replacement for the OEM foam filter.

Thanks for the info!

Picky is an understatement. Suzuki must have put a lot of time into tuning the airbox to get the bike to run with the incredibly lean fuel screw settings and tiny main jets. I have the L model, and merely removing one of the small side access panels will prevent the bike from revving past 5000 rpm. Any real modification to the airbox would be a jetting nightmare.

[Anonymous]

I pulled the rest of the plugs all tan. I tried the filter 2 diffrent times same problems. The bike has 9200miles on it. As far as I know I did not over oil it. By what I can see this model air filter has a lot less area to pull air thru it, It seems to be a paper element. It's a very expensive lesson. On this model the foam filter has a lot more area to pull air thru.

I did run the bike without any air filter in it, side panels attached. It ran like a raped ape ( Only did it for a short distance ) in every gear.

[opiewontaylor]

I pulled the rest of the plugs all tan. I tried the filter 2 diffrent times same problems. The bike has 9200miles on it. As far as I know I did not over oil it. By what I can see this model air filter has a lot less area to pull air thru it, It seems to be a paper element. It's a very expensive lesson. On this model the foam filter has a lot more area to pull air thru.

I did run the bike without any air filter in it, side panels attached. It ran like a raped ape ( Only did it for a short distance ) in every gear.

Okay. But don't misunderstand, I'm not doubting what you say. I guess I just find it incredible, since I use K&N on everything (except my 850). I have their intake kit on a Chevy, and one of their standard filters on a Honda dual sport bike. K&N uses cotton gauze, not paper, and it's very free flowing. They come pre-oiled if you buy them new, and if you clean one, they have to be very lightly oiled (not dripping. You also cannot use anything but their oil. I suppose they could have screwed up on this particular model filter though. Let me know if you decide to unload it cheap.