'82 XJ650RJ Seca not starting, out of ideas.

Hello fellow XJ owners. I'm not sure where to carry on from here, she won't start. I have new spark plugs in and good spark. After cranking a little bit the spark plugs come out with little droplets of fuel on them, so I know there's fuel coming through, however I don't know if the mixture is proper. I've tried all mannor of adjusting the choke/idle screw/pilot screw/fully open throttle. I took the petcock apart and cleaned it quite thoroughly, although no new gaskets, just reinstalled the old ones because I haven't ordered new ones yet. There's fresh oil, fully charged battery. It was sitting for a couple years before I purchased it a couple months ago, and couldn't start. I cleaned the carbs and got it to run, however unevenly, it ran! (was my first time doing carbs, so perhaps I didn't follow the 'church of clean' well enough?) . Then I've been doing some other work on it, forks/brakes/etc. and now it won't start again. If I leave it alone for a few hours or over night, and then hit the starter again, it give one or two pops, as if it's going to catch, but then nothing. Such a tease.
Theories:
- Old dried fuel hoses aren't air tight and causing a vacuum fail??
- Petcock needs a proper overhaul with gaskets to create a proper vacuum??
- Floats aren't set properly causing too much/little fuel?
- Need a new float needle perhaps??
- I need to drink a beer and stare at it for a couple hours till the problem solves itself?
- Mainly I think it is a fuel mixture thing. But I'm very new to the XJ's and motorcycle maintenance in the whole, so I'm not sure where to begin.

Thanks for the help, I hope everyone is enjoying some riding before the winter kicks in!

 

Based on your post it is going to be hard for anybody to troubleshoot your bike.

When issues like this come up you may want to be methodical and eliminate one variable at a time.

Are your valves in spec?

How old is your battery?

Are your carbs setup right? (Clean, floats wet set, sync, idle screws, idle mixture)

Have you tested your coils?

Too many variables to find out so you may want to eliminate them one at a time and make sure that everythingis working. Remember that you need air, fuel and a spark to get it started, if either one is abscent The bike won't run.

Best wishes.

 

1. Set the petcock on PRI. This will bypass the vacuum function of it
2. Test for spark. Use a tester, or just a plug with the electrode grounded to the block. Pro tip - don't hold the plug with your hand while you do this.

 

Did you do a compression test yet? If not do as advised get the valves in spec then compression test the mill. You'll also need a multimeter if you don't have one. Is the fuse box old or new(er)? Did you bench synch the carbs? As eco stated...to many variables (a.k.a unkept scheduled maintenance items).

Gary H.

 

Yes, I already got all the part/tools ready for my valve adjustment, got them in the mail from Len the other day. Was having quite a moment of frustration this morning when I couldn't get it started. But you are reaffirming all the things on my check list, so I'm once again motivated! Thank you!

 

We've all been frustrated at some point. Good news...we are all here to help and learn from each other. Truth...the only people that do not get their bikes running correctly are the ones that avoid the advice given. Stay with it, you'll get it.

Gary H.

 

Quit trying to get it to run until you've done some basics so it has a half a chance.

Check and adjust the valve clearances and get a compression test afterward. Then once we've confirmed that you have a viable mill, you'll need to get the carbs in condition to be able to actually run the motor without filling it with gasoline.

There is a "process" here; and you can't shortcut it (OK, you can but it won't work.)

We've all been there; and we've all been frustrated. Understand that a 30+ year old motorcycle is not like a used car of similar vintage; and if you want to ride it some work ("some" he said, LOL) is necessary to get it to run right.

Then we'll discuss brakes.

 

Only one exhaust valve is out of spec by .02mm. But the other three exhaust valves are right on the cusp of being too tight, would it be advisable to get new shims for all four? Since they would go up by .05mm they would all be .01mm too lose though.

 

You still don't say if you tested for spark.

 

I'm thinking he has tested for spark.

In spec is in spec on the valves, just re-shim the one to get it in spec, and then do as bigfitz52 suggested

 

True in spec is in spec but .01mm is really small. Imo it'd be best to go ahead and change them all now while he's in there. The .01mm will tighten soon enough. They should all be in spec at the next 5k valve check.

Gary

 

Sounds more like the enrichment circuits are still clogged. Have you tried some starter fluid?

Another simple thing to check--- has a critter filled up the airbox with a nest that is stifling the air flow?