Won't start, No idle, weird throttle response

Here's the problem I'm having:

The bike won't start cold. The motor turns over freely, and the electricals work, but there's no combustion

After push starting the bike (which is getting harder and harder to do), the throttle response is very mushy, and the bike will accelerate at random times for a few seconds

If I disengage the clutch, the bike dies. If I let off the throttle, it dies. There is absolutely no idle.

I've replaced spark plugs, fuel/oil/air filters, choke/throttle/clutch cables, and the chain. I took the carbs off to clean them but never actually did; I ended up putting them back on the bike after about an hour. All I did was take the bowls off, look at them, and put them back on.

The bike idled and ran before I did any of that, but still had the starting problem. I assume I must have done something in taking the carbs off but I can't imagine what. I really need to get this thing running but have no idea where to begin. Please help!

 

Start by pulling the carbs and throughly cleaning them. Search the posts here there are plenty of "how to" articles. Make sure the carb slides are clean and move free, search for " clunk test ". Also make sure the pilot circuit is clean. Don't just take the bowls off and spray carb cleaner, take everything apart and clean. Clean , set floats and be sure to sync the carbs after they are installed.
When you replaced the plugs did you put the wires back on right. One coil fires cylinder 1 and 4 , the other does 2 and 3.
Does your starter work. I would think not since you are push starting.

 

Take a deep breath and relax. I think just about everybody on this site has gone through this.

sounds like you have carb issues. there are alot of good instructions on cleaning carbs on this site already so I won't recreate the wheel.

The one thing is in the float bowl is a tiny non removable pilot jet that could probably get clogged by a piece of dust thats how small it is. Chacal for xj4ever on this site has a drill bit the correct size. People also use thin guitar strings to unclog. Personally I used a tiny welder tip cleaning bit.

believe me if you clean the carbs completely, adjust fuel level or floats, synch carbs on the bike and adjust idle mixture when your done you will be amazed.

You don't have to split carbs from each other just dissasemble the inards of each carb. I cleaned mine by using a homemade ultrsonic cleaner.

Aluminum pan with palm sander duct taped to the bottom. Put mr. clean and water in pan and turned it on for about an hour and a half. The crap that came out even after cleaning with spray cleaner was unbelievable.

Before you do anything read, read and read some more. it will make the job alot easier in the end.

 

Thanks for the help guys! The spark plugs are correct and I assume the starter works because I can hear the engine turning over when I try to start it. I sort of had a feeling I should clean the carbs but didn't want to tear into them if it wasn't necessary; now it doesn't seem like I have a choice. I'll be sure to read all I can. Thanks again

 

Get a shop manual, the Clymer or scrounge up a factory book on eBay (just be sure it has the Maxim supplement.)

Check your rear brake shoes for delamination before you ride it at all.

Take a good close (and careful) look at the fusebox.

You can't just latch onto a quarter-century old bike and start riding it-- not only is it dangerous but it won't stay running long. Get a book and take command of the process, or you'll get nowhere. We're here to help, but you will need a manual.

 

Yep. Carb issue. And its sad cause the carbs always always get ignored. That should be the first thing you do along with fluids, battery, ect. You know, BASIC tune up. Carbs are the heart of your bike, truck, jet ski, ect ect. Just do it, and your vehicle will reward you
-Chris

 

I got a manual and replaced the fusebox with one from Chacal pretty soon after getting the bike (when I got it it had aluminum foil connecting a few wires...). Delamination, you say? I'll be sure to check for that as soon as I finish with the carbs. Thanks again for all the help

 

Ok, so I finished cleaning the carbs, and wow, what a difference! The bike started right up, idled beautifully, and gave me no trouble...for about five minutes. I took it around the block a few times and about five minutes into it the old problem started back up. If I pulled the clutch, it would die, and if I let the rpm's get too low, it would die. Now it won't start, just like before. I can't imagine the carbs getting dirty again after five minutes of riding...or could they?

 

I bet the gas tank is loaded with red crap. (rust)

It's probably cycling crud right back into your carbs.

 

Or the cas cap needs a refurb (plugged vent.)

Hopefully, you have already installed an inline fuel filter?

If not, then you may very well have crudded up the carbs again, sorry.

 

I installed a fuel filter, the kind that goes into the top of the petcock. Do I need an in-line one as well?

 

In lines are ALWAYS a plus. If you can route the BIG one itll last forever. Little ones clog fast when there is stuff in the tank. (Learned that on the Ninja)
As for your idling issue.
I'm going on a limb, but did you bench sync?
What were you idling at when she was all warmed up?
-Chris

Oh! And see? Clean carbs are happy carbs

EDIT: And agreed with Fitz. Plugged gas caps are an easy check as well.

 

I did a bench sync, and when I started it up I was idling at about 3000. I Tuned it down to somewhere in the 1500-2000 range and it still worked fine, i guess until I crudded up the carbs again. (On a side note, what should I be idling at when everything's working well?)

Anybody know if auto shops sell in line filters that will fit? I don't have a bike shop around me and I'd like to have it running asap, or else I would order one from Chacal. Am i mistaken, or is it true that as long as the hose fits, the filter will work?

 

Something that I missed earlier, and now that I see it, it looks problematic:

I don't know if that hole is supposed to be there, but whatever the PO did to seal it up seems to be really fragile. I can scrape pieces off with my finger.

 

I just checked my bike. It is cast solid - no hole or screw adjustment.

My guess is that it is cast into the carb body so that if the manufacturer was using just one carb, they could drill and install the idle adjustment screw.

It should be plugged off.

 

Those blanked-off ports are for the fuel distribution pipe. The carb body castings are the same for all 4, but the passages are drilled differently depending on the position of the carb in the rack.

If you pick the "filler" out and the hole is actually open behind it, it's because somebody has swapped a carb body from a different rack position. You may need to re-plug the hole, a "Welsh plug" is the correct way of doing that.

You should be able to get an inline fuel filter for 1/4" line at any NAPA store.

The 550 should idle at 1200rpm.