Smoke Gets In Your Eyes!!!

[SlickRick]

Left off from: Too much gas!!

Hello. Need more help. I took carbs off and put floats in them and cleaned it. Finally got it started and choke idle is touchy, push it in and it slows idle. Barely idles with choke in.
I have smoke coming out of the left exhaust and power seems to be weaker than right.

Smoke is a light white/blue. What are my next steps for correction?

PS> What is the speed that the xs400 will cruise at comfortable for long trips?

Thanks again for all the help.

 

[XSLeo]

When you put in floats did you adjust them to spec?
The white to blue exhaust is an indicater of excess oil in the combustion chamber.
Possibly bad valve stem seals, rings, headgasket.
Leo

 

[SlickRick]

Around 27mm. The choke seems to work in reverse and rpm's go down to 900 when warm and choke is all the way. What to check at this point???

 

[bcware]

Any mods to the intake or exhaust? What size jets do you have? Did you synch the carbs? Have you adjusted the idle? How many turns out are the idle mix screws?

 

[dO-bOy]

The Xs seems comfortable at 110kph with stock gearing

 

[SlickRick]

Happy Memorial Day. Here is what I did today so far. Put more gas in the tank to thin out the heavy Seafoam/gas mixture I had in there. Compression tested at 90? sounds high. Put the air cleaners back on for this test. Cold start w/ choke all the way out it started roughly but went to 1500 rpm dropping to 1200 rpm. waited and then pushed choke in one time and rpm's went up to 1500 and after waiting awhile it stayed. Pushed choke all the way in rpm's drop to 1,000 then 900 and steady at that. I then revved up the bike a couple of time and got it up to 1,000 rpm plus turning the throttle screw up.
With all that I still have white smoke coming from the left exhaust. Everything is stock and I am assuming the carb parts are too. That's the update. What are my next steps from here.
Thanks for all your help.

 

[SlickRick]

Hi, a quick change of subject. I have my "82" XS400SJ speedo off. It is all plastic. How do you get the face top off to get at the face plate. It looks like it either unscrews off or pops off?

Thanks

 

[JARichmond]

Compression should be sitting up around 140-150 so I think you're actually very low. Ensure that your compression is being tested with the throttle wide open and air boxes off. If your compression is still very low then you may have some blown rings or a poorly adjusted valve seating. Rings would cause super low compression and an oily exhaust.
As for your revving situation, try to get your idle to stay steady at 1200-1250 rpm using your idle adjustment screw (like you were doing) without choke. A properly adjusted fuel system will cause the bike to rev high at operating temperature with the choke on. If it doesn't work properly then you may have to mess with your idle mix screws or clean your carbs again. Remember, stock setting is lean and should be around 3 turns from lightly seated.
I recall reading somewhere that the speedometer is a press fit. Sandrew's build thread detailed him removing the faces, so a definite answer would come from that thread.

 

[SlickRick]

Hi, ok got the compression to redo, and a press on head sounds permanent unless forced off (breaking something). All I need is to get a tiny screw back on the face of the speedo. I might be able to drill a whole thru and put a screw in that way. I will try to find the thread.

Thanks

 

[DanMach]

For what its worth, my 400J(Which I think you have?), after choke and once its warmed up idles around 1500. I know the manual calls for 1250, and I can adjust the throttle screw to get it there easily enough, but I very rarely idle more than 30 seconds at a stop light so I highly doubt its doing any damage.

Also, even in the winter(40 out), with the choke on the bike will start and idle around 1200 for about 10-30 seconds before it starts picking up to idle around 4k or so with full choke on. I usually go to half choke, and it sits a bit above 2k, for about 10 seconds or so before I go. Its air cooled, it doesn't take too long to warm up.

 

[OliverB]

Remember, you have carbs, not fuel injection, so a partially warmed engine off choke may still not be up to normal idle speed as when fully warmed up. Did you adjust the idle speed screw to raise idle up a little?

Side note: Even though factory specs call for 1200 rpm, you can safely idle at 1500 w/o concern. No damage will be done. Some folks like a little higher idle.

 

[SlickRick]

Hi, Adjusting said idle. Seems to work better but still on the low side. My speedo is pressed on and fixed that with a dremel and used silicon adhesive to put back on.

Thanks