burning oil

I replaced the stator brushes and that seems to have gotten rid of the stalling when going up hill. In fact, now I have the opposite problem.

The RPMs get stuck at 3 or 4k when I let go of the throttle. It's also smoking like crazy and backfiring when I stop. The engine is super hot after a 3 mile ride.

It sounds like it's rattling and misfiring so I'm going to check the plugs, but what is causing the smoke? I know it has enough oil...

 

It sounds like you have serious carburetor issues and also possibly too much oil.

The hanging idle is generally due to carburetor sync and/or float levels;

and a stuck float can fill your motor with gas, diluting the oil and causing the crankcase to "overfill" which then pumps into the airbox.

STOP trying to run the bike. Remove the oil filler plug and have a whiff. If it smells like gas, you have the above-described issue.

Check the air filter for oil-fouling.

It's also a common mistake to simply overfill the motor. How are you checking the oil level?

 

Thanks Fitz. I smelled the oil and did not immediately smell gas. It just smelled oily to me, but that may not be the best way to judge. I will also check the air filter.

I recently changed the oil and filter, and put in 3 quarts.

sounds like there's some miss firing when it's in gear at low rpms. I'll check the plugs too.

I've been avoiding the carbs, but it's time.

 

You been avoiding the valve clearances too?

You may have overfilled a tad; I'm not sure what your oil capacity is. There's a small number, on the 550s it's "2200CM3" cast into the cover right by the filler. That's your oil capacity in CC's (CM3) so in my case, it's 2200CCs, or 2.2L. Plus maybe 200CC's to keep the oil level sensor happy under acceleration. See what yours is; 3 quarts is probably a bit much.

Check the oil with the bike on the centerstand (or held vertical) and the motor off for at least 5 ~ 10 minutes. The oil level in the sight glass should be above the upper marks but with a slight "bubble" showing at the top.

 

Okay, the air filter smelt oily, which should definitely not be the case. So I will assume gas got into the oil. I will change it, but do I need to get a new filter?

I've been avoiding jobs that require me to buy more tools, but I guess that's what I've gotten myself into.

 

For the price of an air filter it's worth replacing for peace of mind (also the oil filter when you change the thinned oil of course )

You don't necessarily need special tools for the valve clearances, see the zip-tie trick. And JIS screwdrivers for the butterflies aren't expensive really.

 

The 700 should take 2,800 CC on a "regular" oil change and something like 3,300 CC's on a "dry" engine. Check your window on the Mainstand.

Valve clearance check/adjust is Step #1 in XJ maintenance,
along with a basic compression test, tire and brake check . . .

You're not going to clean your carbs - you're going to Race Prep your carbs!
There are many details that need to be addressed to make your carbs perform like new - read Church of Clean and Nine Yards. On this site.

 

Some say, ... the most important rule of motorcycle fixing is:

"Don't do anything that will make a bad situation worse!"

Not having the right tools to work on your Bike is a bad situation.
Trying to work on you Bike without proper tools makes the situation worse.

Buy tools from Sears ... when they go on sale.
Or ...
Craftsmen Outlet.
Or ...
Harbor Freight.

Some kind 'oh way.
Tool-up. You'll save yourself some misery.

 

What tools?

Metric feeler gauge: $8.

Plus you'll need a 19mm open-end wrench, 5mm allen wrench and hex bit for your 3/8 drive set. You probably have that covered, since you had the alternator cover off.

You don't absolutely have to have the bucket hold-down tool; but if you want to use one it's a whopping $20 or less.

Like Rick says, TOOL UP! A man can never have too many tools. Avoid buying tools-- come to your senses good sir!

And if you buy quality tools, they last forever.

 

Cruise the Pawn Shops - they have a loose tool bin (sometimes) you can get Name-Brand tools for 0.10c on the $

 

Yeah, I'm tooling up. Don't I need a vacuum sync and the YICS tool to resync the carbs? Is it possible to free up a sticking float without disassembling the whole thing?

 

A sticking float is a precursor to "Serious Cleaning Needed"

If you don't know when the Carbs were last cleaned, ... they're due!

 

True true I figured as alternator brushes had been done, that meant a selection of "normal" tools & the O/P was referring to avoiding buying many special tools, which apart from JIS screwdrivers and METRIC feeler gauges, isn't really essential if you follow some of the guides on here. Having all the kit ready to hand though (and knowing how to use it) is a nice feeling...

If money's tight you can make your own YICS tool for about $10 or less, your own sync gauges for around the same & shims can be changed with a large zip-tie although for the money the tool is nice to have provided you're careful with it (The zip-tie method is a bit fiddly, and whichever way you're doing shims you should be in "fully careful" mode anyhow )

100% agreed, fully service the carbs using church of clean & 9 yards threads on here, replacing any & all parts that need it and you'll have a bike you won't even recognise once the valves & running sync are completed too.