What the heck could I have done to my 1100 engine??

[Road_Clam]

I finally got my carbs all finished. They have been dipped, I installed a Dynajet kit, and basically went right through them. I fire up my bike, and to my horror, it runs so pi$$ poor, I cant even describe it. I need 1/2 choke for it to stay running, and I hear a slight pop through one of the carbs. I slightly crack the throttle, and it instantly bogs and will stall. I pulled the carbs, I must have forgotten something major. Nope, everything looks perfect. (these carbs were reasonably clean to begin with). It is getting fuel, as I spray raw fuel in each cyl, and each one will lower engine rpm's. I completely stripped this bike to the frame, I am wondering do I have something questionable in the ignition? All cyl, have spark. I did a valve adj., and all the valves were close. I found a less than ideal ground on that ignition component that is bolted to the battery box, but I have not re tested the engine. GOD I hope I find this problem. ANY experiences would be great!
Rich

 

[RacingJake]

Since you say it need's 1/2 choke to stay running, then it's a fuel problem.

The DJ's may be smaller than the jet's you took out. Check the size cause DJ's are smaller than a mikuni's with the same number.

Float level too low.

Stuck needle valve's in the carbs.

Metering rod set to low.

You can always put the old jets back in and see what happens.

 

[Road_Clam]

Let me clairify, it runs slightly better with the 1/2 choke. If I shut the choke off, it will idle, but it will slowly stall over the course of 20 seconds. The mains I have installed are 114's. Stock is 107.5's. I't just doesn't make logic. All stock, the engine ran excellent once off the pilot circut, and I had a plugged #2 pilot jet. I am so stumped, and pi$$ed. I generally can almost always systematically figure issues out (especially considering this thing runs SO bad right now). If there is fuel in the bowls, and the mains are clear, and you have spark, it should a least rev up!

 

[Tarbash 27]

if the bike is completely stock, why did you get bigger main jets. this will cause it to run richer. if its stock, put all the stock parts back in it and see what it does.

 

[Road_Clam]

if the bike is completely stock, why did you get bigger main jets. this will cause it to run richer. if its stock, put all the stock parts back in it and see what it does.

Because I added a performance 4 into 1 exhaust. Once you add a performance exhaust, you are about guaranteed to be running a stock bike too lean. Strict EPA regulations pushes the factories to jet stock bikes so lean they barely run good. (especially in colder weather)

 

[robinjo]

Did you turn the air screws out to 2.5 turns?
Are all four pipes warming up?

 

[toymechanic.]

You may know this but in case you don't. The engine will not run worth a crap unless the air box is on and the hoses all tightened down.

What size pilot jets (40, 45, etc) and pilot air jets (160, 170, etc.) did you put in it? Use the original ones. Just increase the main jets for the pipe.

 

[retrex]

Been there

Been there

You may know this but in case you don't. The engine will not run worth a crap unless the air box is on and the hoses all tightened down.

Ditto this.

 

[Road_Clam]

You may know this but in case you don't. The engine will not run worth a crap unless the air box is on and the hoses all tightened down.

What size pilot jets (40, 45, etc) and pilot air jets (160, 170, etc.) did you put in it? Use the original ones. Just increase the main jets for the pipe.

Interesting, I have been trying to run my bike less the complete airbox. I wonder if that's it. (if it is, you are my hero, and I owe you a 30 pack of "beverage")!!!! I will reinstall the carbs with the complete air box assembly, and get back to you. I have #45 pilots, and a 160 air bleed jet. Thanks for the info
Rich

 

[argonsagas]

Re: Been there

Re: Been there

You may know this but in case you don't. The engine will not run worth a crap unless the air box is on and the hoses all tightened down.

Ditto this.

It may sound strange, but it is definitely true.

Some of us have learned it from experience.

 

[crag antler]

if the bike is completely stock, why did you get bigger main jets. this will cause it to run richer. if its stock, put all the stock parts back in it and see what it does.

Because I added a performance 4 into 1 exhaust. Once you add a performance exhaust, you are about guaranteed to be running a stock bike too lean. Strict EPA regulations pushes the factories to jet stock bikes so lean they barely run good. (especially in colder weather)

Is this true for a stock bike with an aftermarket pipe or ??
My 83 GS1100E is box stock except for minor electrical.
With 40k miles and running well, she has no difficulty at all starting up at 25F to ride to work with me :twisted: :twisted: :twisted:
She is a little cold blooded in the summer but roars in the winter.
Just wished it didn't snow today :? :? :wink:

 

[Road_Clam]

if the bike is completely stock, why did you get bigger main jets. this will cause it to run richer. if its stock, put all the stock parts back in it and see what it does.

Because I added a performance 4 into 1 exhaust. Once you add a performance exhaust, you are about guaranteed to be running a stock bike too lean. Strict EPA regulations pushes the factories to jet stock bikes so lean they barely run good. (especially in colder weather)

Is this true for a stock bike with an aftermarket pipe or ??
My 83 GS1100E is box stock except for minor electrical.
With 40k miles and running well, she has no difficulty at all starting up at 25F to ride to work with me :twisted: :twisted: :twisted:
She is a little cold blooded in the summer but roars in the winter.
Just wished it didn't snow today :? :? :wink:

Generally speaking, almost ANY current bike will benifit from a jet kit, even stock bikes with stock exhausts. Once you add a full performance system, and don't add a jet kit, my experience is a very "flat" feeling midrange power delivery, and studdery low speed drivability a tell tale sign that an engine is running a bit too lean is having to use the choke for an extended period of time (like 10 min. of driving). You pull a set of plugs on a stock motorcycle, and the plugs will be ash white. Running an A/F ratio that lean is perfect for EPA compliance, but for the consumer, it causes an engine to run hotter, and festers detonation.

 

[drewshotrodding]

if you bought a jet kit from dyno jet or from another company you can call dynojet look them up on line or in your paper work and call them . when you change pipes and go with after market air filter you will change to a stage 3 kit If you go with pipes and stock airbox and K&n for the stock air filter you will use stage 1 did you drill out the idle air mix screws and turn them out to what it said ?? change out the main jet to what it said?? ALSO DID YOU PUT BACK IN THE RUBBER PLUGS THERE IS ONE ON EACH CARB YOUR BIKE WILL RUN LIKE CRAP NO MATTER WHAT YOU DO now if you drill what instruction said with the right drill bits?? after all that you might have to go up or down on jetting , move the needles up or down Rember 0-3000 is idle jet 3000-6500 is needle 6500 to full out is main jet ,,,,,,, if best ask ???or pay someone before you break your bike

 

[Road_Clam]

A Follow Up, Issue Solved!!!!!!!!!!!!!

A Follow Up, Issue Solved!!!!!!!!!!!!!

I finally got my carbs all finished. They have been dipped, I installed a Dynajet kit, and basically went right through them. I fire up my bike, and to my horror, it runs so pi$$ poor, I cant even describe it. I need 1/2 choke for it to stay running, and I hear a slight pop through one of the carbs. I slightly crack the throttle, and it instantly bogs and will stall. I pulled the carbs, I must have forgotten something major. Nope, everything looks perfect. (these carbs were reasonably clean to begin with). It is getting fuel, as I spray raw fuel in each cyl, and each one will lower engine rpm's. I completely stripped this bike to the frame, I am wondering do I have something questionable in the ignition? All cyl, have spark. I did a valve adj., and all the valves were close. I found a less than ideal ground on that ignition component that is bolted to the battery box, but I have not re tested the engine. GOD I hope I find this problem. ANY experiences would be great!
Rich

I've been around dirt bikes, street bikes ATV's, you name it for about 22 years. I am an amatuer (at best) mechanic, and I generally can always systematically figure issues out, but NOT the above problem. I just got off the phone with my secret "GS Guru" "Jay" who after some experienced diagnostic work figured out exactly what my engine problems was. First off, it had absolutely NOTHING to do with "me" (or what I thought was lack of mechanical abilities). I thought for sure I screwed something up in the engine during my 7 month resotration. In short, my carbs were simply jetted WAY too rich!!!!!!! I am astounded, and VERY, VERY PI$$ED! (As I installed a "Factory" jet kit per the exact recomendation for my bike). All Jay did was "shim" the stock needle, and synch the carbs. The bike purs, and has a sweet crispy throttle response. He recommended a performance dyno company near Boston that dyno's bikes, and "EGT's" the cylinders, for spot on jetting. This will be a must do IMO. So basically I have 114 mains, stock shimmed needles, and stock 45 pilots.

 

[Jethro]

He recommended a performance dyno company near Boston that dyno's bikes, and "EGT's" the cylinders, for spot on jetting. This will be a must do IMO.

What place is that? I was gonna have a Dyno and gas analysis done last year in Nashua at Rons, but he had a 4 month waiting list!

and pilot air jets (160, 170, etc.) did you put in it? Use the original ones.

Stock pilot air jets for the 1100E's are 180. Just FYI.