Bike acting up/Bogging down?????

So just went for a ride on my 93 xj600 seca.....

Ran fine for 20 miles or so and then as I started to get into some twisties it started bogging down.... It kept doing it along my ride, not always at slow speed or fast, in any particular gear, or at any particular rpm...

The bike was still running, but it was almost like it was running on 2cyl or something, If I pulled the clutch in and rev'd it it would clean up and run fine, but it was really kinda worrysome. the only other time I've felt something close was when I was almost out of fuel. But revving it didn't exactly clean it up then, switching to reserve did....

I did switch to reserve to see if it made any difference, no.

So I' just got home, am going to pull of the tank and check the carb boots to see if it's a vac leak or something??? I know one of my fuel line's needs replacement, could it be collapsing on me and killing fuel supply?

Could it be something worse inside the carbs? or maybe something electrical??? Going to work through wotever troubleshooting came w/ the manual that relates, but in the meantime would appreciate any ideas...

Thanks

Koi

 

Do you have an inline fuel filter?

Sounds to me like crud in the carbs, crud in the fuel filter, crud in the filter screens or a petcock or other fuel system issue. And in your case I do mean "system."

To begin with, the Seca II has something the earlier XJs DON'T have: A fuel pump. Have fun with that.

UNFORTUNATELY, if yours is a "California" model, it also has something called a "roll-over valve" and an evap canister as part of the fuel system, in addition to all the other new-fangled complexity.

It doesn't sound like a vacuum leak; it does sound like a fuel delivery issue, and you've got a lot more parts to hassle with than the simple gravity and vacuum-operated systems on the earlier bikes.

You're going to need the manual, seriously. I have no idea where to suggest you start troubleshooting the fuel pump or the "roll-over valve" whatever that is; and crud anywhere in the system could be the cause. Don't just start guessing; you're going to have to methodical.

 

+1 on the above, but here's what happend to me recently.

My '85xj700n also started with similar symtoms.
She continude to get worse and worse although everything within the
fuel/air delivery system checked out fine.

Then she started to backfire and stall. Lights dimmed. barely got her
home.

I pulled the gen cover to check the brushes and found a big a$$ short
in the brush harness that had made contact with the rotor.
This fried the WHOLE SYSTEM.

$500.00 later (including a new timing chain) and she's as good as new.

 

So I did not have a inline filter installed....

I do now

I also took the advice from another bike-buddy to throw some gum-out through it, as he put it, it'll knock the big chunk through and MAKE you clean your carbs, or it'll break the lil chunk through and you'll be fine.

unfortunately it's now raining so I'm gonna wait before running the tank through.

 

For future reference: Don't do that again. Gas, or gas with Sta-Bil in it for when it's stored (if ever.) Nothing else. You pick the wrong crap to dump in it and you WILL get to know that fuel pump.

 

Sounds real similar to what mine was doing last week. Mine seemed like it was starving for fuel at low rpms and sometimes higher, in all gears. Also, appeared to idle fine.

Another member and I cleaned/inspected/rebuilt the carbs yesterday. They were a little dirty but nothing clogged or malfunctioning. Got them back on the bike and it was still acting up.

So, we started pulling plug wires and discovered one or more of the plugs was almost shot and wasn't firing consistently. We closed the plug gap a bit and its running fine now. Im gonna get a new set tmw.

Checking the plugs is easy. Warm up the bike then pull one plug wire at a time. If the plug is good and the cylinder is firing properly, you will hear the exhaust soften a little bit when that cylinder stops firing. If you do not hear a difference, the cylinder is not firing, could be the plug or wire.

My bad plug must have had a weak spark at lower rpms then picked up and fired when revved.

Remember to try all the easy stuff first. good luck

 

+1^^^ You can do a LOT of damage putting the wrong thing/quantity in your fuel system. Avoid it like the plage and fix fuel system problems correctly.
And good on you for getting that in-line filter in there, you just bought yourself some cheap insurance and a handy troubleshooting tool (provided it is clear).

 

Gotta give a +1 to albert for bringing up plugs.

Rode through a tank and half of gas, no problems
was out again for a ride and it started acting up, When I couldn't get it to clean up I reached down to hit the choke and see if that worked and remembered the spark-post on this site, reached down and pushed on the top of the #1 plug wire and felt it give just a little bit, and as soon as it did it also cleaned right up. Hasn't missed once since then....

Thanks!

 

Glad you got it working. Haven't seen ya around here in a while, yo!

 

Passed my DMV license test so been putting on some serious mileage, and now that the bike isn't acting up I haven't had much to say.

Gonna be doing the clutch here soon, so will post some pics of my job as I do it.

Going to the moto-jam event here at infineon this weekend, pics of that too unless it's raining

 

Yea i just did my clutch -- well sort of -- I put the old friction plates back in for now since I was diagnosing a problem, but I'm gonna get new plates from Chacal soon.

Point being, the clutch is a piece o' cake.

 

I picked up a set of frictions, steels and springs on ebay for 60 bux for mine

yeah I know it's easy, just been lazy and riding more then working