my bike blew up twice in on week

[channing]

i bought a honda 400 ex 2001 drove it for five minutes it started making a bad engfine noise i took the head off sure enough the piston was all chewed up,
had the head bored over .040 got new wiseco pistin new valves
put i it back together sounded good noise gone. go for slow ride
starts pinging real loud seizes up wait five minutes strts up sounds good take off , pings shakes stalls
anyone know why

[Chino]

valves adjusted properly?
is it in time?
sure the piston isn't in backwards?
Timing chain good?
Make sure the choke is off and not sticking, also try turning the idle up some.
Make sure it's properly jetted, after doing some motor work along with a exhaust it's going to need jetted probably running very lean. That could be causing the spitter/sputter sound like it's dying.


If you can't figure it out let me know, I'm not far from Morgantown and I can try and help you out the best I can or lead you in the right direction.

is it jetting correctly

[boondockman]

Make sure that the oil is circulating though the engine properly.

[hondajoe05]

^^ Yep

[rooster_20]

That has to be a record!

[channing]

is it safe to buy afermarket parts off the internet I seen a crank for $198 made buy hot rod cranks sounded to good to be true?

[EXevan91]

chino how do u put a piston in backards ?

[jordan_m6]

make sure ring gaps are on opp. sides , make sure no up and down movement is in the crank if so change crank barrings, make sure arrow is pointing to front if directions say front with my weiseco thats how it was. then make sure your timing chain is not jumping time if so replace chain.

thats some things to follow when rebuilding not sure what kind of exp. you have but i had two people helping me

[JOEX]

Originally posted by EXevan91
chino how do u put a piston in backards ?
By turning it around:p

Some if not most or all aftermarket pistons should be installed in a certain direction usually indicated by an arrow stamped on the top of the piston. If I remember correctly the arrow points to the exhaust side of the air flow.

I'm pretty sure the main reason is because of the valve cutouts in the piston. The intake valves cutouts are larger than the exhaust.

There very well could be some other or different reasons.....

[Chino]

Originally posted by JOEX
By turning it around:p

Some if not most or all aftermarket pistons should be installed in a certain direction usually indicated by an arrow stamped on the top of the piston. If I remember correctly the arrow points to the exhaust side of the air flow.

I'm pretty sure the main reason is because of the valve cutouts in the piston. The intake valves cutouts are larger than the exhaust.

There very well could be some other or different reasons.....


exactly, and if something can be put in the wrong way im sure many people have made this mistake. I was just listing some of the possible reasonings from the top of my head that it did not start. It's hard when you can't see the bike and actually work on it so why not list options that it could be.