400ex smoking

[dabrowat]

What could be the cause for it to smoke white smoke? Thanks

[the freak]

my 400 does that and found that it was comming from the packing.......................old pipe

[dariusld]

How old is your bike?

[flamed360]

Mine did it and it was the valve seals

[dabrowat]

Its a 2003. It has a White Bros. E Series. Could it be taking oil because I noticed there is less oil then when I checked before i went riding.

[DF400ex]

if your valve seals are going then oil will leak into the cylinder causing less oil in the engine after a long ride. This usually only happens on start up because the valves expand from the heat and make up for the bad seals. If you are throwing smoke the whole time it could be really bad valve seals or rings.

[dabrowat]

Its smoking the whole time. I notice there was less oil after riding on sunday. Do you know what the price would be for a valve seal replacement? Thanks

[Topeka-440]

could you do a compression test on this as you would a car engine? Start with a base line reading, then squirt a little oil in the cylinder and check again. If the compression go's up then that would be an indication that the rings are bad. If the compression stays the same then your valve seals may be bad. This is just an idea, I'm still learning myself.

[DF400ex]

that should work

[blasterheavyB]

i had almost the same problem but the smoke was black and it was my piston rings but when i talked to the macanic about it i thought it was the valves but he said that they do not hardly ever go out on a bike so i would say it is probably not your valves

[blasterheavyB]

i had almost the same problem but the smoke was black and it was my piston rings but when i talked to the macanic about it i thought it was the valves but he said that they do not hardly ever go out on a bike so i would say it is probably not your valves

[blasterheavyB]

i had almost the same problem but the smoke was black and it was my piston rings but when i talked to the macanic about it i thought it was the valves but he said that they do not hardly ever go out on a bike so i would say it is probably not your valves

[dabrowat]

So should I do a compression test and see what the problem is??

[dabrowat]

If the rings are bad, would it be taking oil and smoking?

[GPracer2500]

Originally posted by dabrowat
If the rings are bad, would it be taking oil and smoking?

yes

[400exrapes]

theres one other thing that ive just fixed this week, my 400ex was smoking after my hmf was installed, if your jetting is too rich then it could smoke it happened to me and i fixed it. Go down one size on your main jet or move to a pilot smaller. what mods do you have i know what temperature your probably at and idk how to help you unless if your at about 300-400 above sea level with the jetting

[dabrowat]

The previous owner bored the cylinder. It has a K&N filter, WB e Series. Is it hard to replace the rings? I live in the Chicagoland area (600 ft above sea level.) I usually ride in 60-80 degree weather.

[400exrapes]

from my experience go down a main jet size or two and if thats no good go down a pilot size one or even two and check your spark plug cause im pretty sure yours must be black now and if its a good color then your carbuerator is fine. good luck

[blasterheavyB]

i am in the process of changing my rings right now so far the hardest part was getting the piston in the cylinder with the ring compresser but i have not finished so the timming is probably going to be messed up then that will be a big problem i let you no today when i get done

[Topeka-440]

I just installed my 440 kit about 3 weeks ago, and the most difficult part was putting the piston into the sleeve to install on engine. I put the piston into the sleeve and then lowered the assembly and installed the piston pin. I didn't have a ring compressor and did it by hand so that may have been my problem. But anyway a very critical thing you need to check when replacing your rings, is to check your ring end gap. I had a local shop do this to make sure it was right. Also be sure to index the ring gaps properly on the piston when installing in the sleeve.

[dabrowat]

How much does the dealer charge for changing the rings?

[400exrapes]

im saying check ur plug and jetting first. you can save alot of time and money

[dabrowat]

Do you have to take all of the plastic off to get to the spark plug?

[GPracer2500]

Smoking from rich jetting is grey/black in color. Smoking form burning oil is white(ish)/blue in color.

[400exrapes]

well put GPracer and that is true. What color is the smoke again?

[dabrowat]

Its a whitish color.

[400exrapes]

if its whitish im not sure my rich jetting had whitish smoke too i say try the jetting and if thats not it then switch the jetting back and then check all your other problems i only know about the carbuerator problems so i cant help you with the others.