need help please

[newton1613]

I have a 03 400ex..it has a 416 piston and i put new valves and kibble white valve springs in it ..and new valve seals. and it still smokes on start up but after it is ran alittle it stops smoking...can anyone help me out ???????????

[jdog75]

its the rings it smokes a little on start up bc their not fully expanded. when it warms up their expanded and everythinf is good. and is it bluish or black smoke

[newton1613]

ok...i havent put rings in it since i put the piston on...and the those rings were used..so i guess i will pull it back apart and put new rings in it...is there any set of rings that r better than another???

[flyboy1294]

Originally posted by newton1613
ok...i havent put rings in it since i put the piston on...and the those rings were used..so i guess i will pull it back apart and put new rings in it...is there any set of rings that r better than another???

Used rings are not a good idea. Honestly, new rings are only a temporary fix. You need a new piston and bore/hone. It's more money, but you will be able to put the engine back together and rest assured that it's done right. Otherwise, you'll be back in the engine in 6 months, tops.

[newton1613]

i dont know how old the piston is but its a wiseco piston..so ur saying not to just put rings in..even if the bore is still in spec.???

[flyboy1294]

Originally posted by newton1613
i dont know how old the piston is but its a wiseco piston..so ur saying not to just put rings in..even if the bore is still in spec.???

You might be able to get away with it, but I'm willing to bet if you're rings are worn then the piston and cylinder are also. So to be safe, I would recommend going up a bore size.

[newton1613]

well i dont really want to go to a 440 kit...

[flyboy1294]

You don't necessarily need to unless the piston you're running now is a 426. Do you know how big it is currently?

[newton1613]

the piston is a 416 86mm.....i checked it today and the piston is 3.334 and my bore is 3.379. so its in not just rings that i need to replace

[barton1398]

A 416 is 87mm

[newton1613]

the number that is stamped in the wiseco piston is 4628m08600..and my atv parts store said its a 416..86mm

[flyboy1294]

If you have a 416 in there you could go up to a 426. It has all the reliability of a stock engine when built well, and also a significant power gain.

[newton1613]

well what i am goin to do is..i have another stock sleeve ..i am goin to get it bored out to the size of the piston i have.. and get new rings

[flyboy1294]

Alright maybe that will do the trick

[newton1613]

man what u talking about..it will do the trick cause its like puting a new sleeve and piston in ...the clearances r goin to be the same if i buy a new one...ur do what i am having done

[miles Machine]

as long as your piston is mint then that would be an option but if not it would be like putting a new chain on old sprockets it will just prematurely wear out

[newton1613]

the piston in still in spec...

[flyboy1294]

Originally posted by newton1613
man what u talking about..it will do the trick cause its like puting a new sleeve and piston in ...the clearances r goin to be the same if i buy a new one...ur do what i am having done

It won't be the same as having a new piston. But it sounds like your piston is in good condition, so it'll work hopefully.

[ian0615]

i would use the new sleeve with a new piston and rings, so many people over look really how important those rings are...if you use used rings they wont "wear in" properly (unless you get really lucky) they will wear wrong and wont create that new solid seal..if your going to spend the money and time getting a new sleeve pressed in you may as well spend like 140 bucks and get a new piston/rings also...will save you time and heartache in the long run. just my .2

[newton1613]

i press the sleeves in and out my self..and i am putting new rings in it..but there is nothing wrong with the piston..