I have a 2002 honda 250ex that i just bought... it ran good after a rode it for a while but then i realized that the clutch was slipping... so i ordered new clutch plates and as we were in there we noticed that the oil pump chain was off... after putting a new (unstreched one) on and getting it all back together i noticed after the first 20 seconds of running that it was smoking alot of blueish smoke(oil) and making a horrable ticking noise that was there before the work but we thought it was becasue the chain was off......could it me that because the oil pump chain was off it was not smoking because there was no oil on the top of the pizton? or the valves got off ajustment after re timing it...(will the valves being un ajusted make it smoke the burnin oil?????? thanks for helping

 

also would it most likely be that the cilinder was not getting enough oil so it fryed my piston and rings?

 

makes me wonder if the previous owner didn't unhook the pump so it wouldn't smoke while people were looking at it? You are probably going to need a piston and rings because they are worn out, but yes the oiling issue would make me hurry up and get it done.

 

ok... do u think i might have to bore it out?

 

blowing bluish smoke is not good for sure.... and if it is ticking i mean really ticking.... then yeah the top end is not getting oil....
worse case the valves are hitting the piston....

either way i would stop riding get your self a manual and tear that top end off.

bored? maybe... you will have to have someplace check the cylinder.... obviously if the piston looks terrible then odds are it trashed the cylinder as well.

to tell you the truth i'm surprised that you didn't seize the piston....

and check my thinking here.

if there was no/very little oil getting to the top end and the bike was drove around for a while (somehow)
and then you torn into it, fixed the pump chain
since oil is now being sent to the top end should hopefully the knocking would go away....

but by now the piston and rings are fried so oil is getting past the rings... and gets burned .... causing your bluish smoke.....
where before it was getting little to no oil so there was nothing to burn.

i'm definitely curious how this bike was running.....
was the chain just missing?
was the bike knocking at all when you got it.?

I'd like to know what that piston looks like....

hope this helps

Duster

 

yes rebuild now.....my 250x was ticking and smoking after runnining it out of oil a couple times ,and now its locked up no telling what i broke ,and you may be able to get yours honed ,and juist go up a ring size ..depinding on how much damage has been done ....but if u blow it youll have to spend lots more $$$$$$

 

ok.....well... the oil pump chain was hanging off the 2 sprokets..1 crank chaft, 2 the oil pump.. we got it back on and the chain was really losse and there is NO tensioner for that chain, therefore the only possible thing is the chain has gottin streched out over time..(by the way the timing chain was after market(my friend said he new becasue of the brand..so i ordered the new chain and we put it on... it is nice and tight..we put it all back together and when i started it it was still making the ticking noice BAD! but after 5seconds of it idleing the ticking went 100% away as before it ticked all the time.... but then if u give it a little gas in nuetral it comes back then if u let it sit it stops and starts..... if u hold it reved a little it sounds like there is no ticking...Could it be that becasue of the worn piston rings that the oil preesure is only good at reving RMPS>>>??? thank u for helping

 

ok.....well... the oil pump chain was hanging off the 2 sprokets..1 crank chaft, 2 the oil pump.. we got it back on and the chain was really losse and there is NO tensioner for that chain, therefore the only possible thing is the chain has gottin streched out over time..(by the way the timing chain was after market(my friend said he new becasue of the brand..so i ordered the new chain and we put it on... it is nice and tight..we put it all back together and when i started it it was still making the ticking noice BAD! but after 5seconds of it idleing the ticking went 100% away as before it ticked all the time.... but then if u give it a little gas in nuetral it comes back then if u let it sit it stops and starts..... if u hold it reved a little it sounds like there is no ticking...Could it be that becasue of the worn piston rings that the oil preesure is only good at reving RMPS>>>??? thank u for helping

 

time to rebuild and hope you dont get such a raw deal next time.

 

i did a comp. check and it was 170psi....the honda dude said it would be ok if you were around 150 so in other words it was really good.. my friend and i are thinkin that sinnce the oil pump is hooked up now its pumpin more oil to the valves and the seal are worn or cracked??? so and as far as the ticking its only when idleing not at a little reved up... makes me wonder if its the valves not getting enough out and the reving pumpes it better... so im goin to put some 20w50 oil in after i put the seals in and see if that helps much... >????????????