what is involved in top end rebulid?

[anabolicsman]

i took my 400ex to get rejetted at the shop and it was smoking alittle bit and today they called and said the rings are flat or something and i would need a top end rebuild and he said it was 850 to do and im wondering is this something i can do or what is all involved

[MO-EX-RIDER]

get a manual...and do it your self

[JOEX]

If you understand the workings of the motor then it's a relatively simple job with a repair manual. Sinec you took it to a shop to get jetted then i'd guess you're not comfortable with working on the motor so it may be better to have someone do the work for you.

You may want to get a second opinion on what needs to be repaired just to make sure the shop isn't fishing for more repair work.

[xc_racer1]

Originally posted by JOEX
If you understand the workings of the motor then it's a relatively simple job with a repair manual. Sinec you took it to a shop to get jetted then i'd guess you're not comfortable with working on the motor so it may be better to have someone do the work for you.

You may want to get a second opinion on what needs to be repaired just to make sure the shop isn't fishing for more repair work.


exactly. if its just smoking then i dont think that it would completely need rebuilt. u could just need it rerung. and that shouldnt be more than $200

[JOEX]

IMO a 'top end rebuild' is a re-ring job and it may only need valve seals if anything at all. Depends on the color of the smoke and when it's smoking.

[xc_racer1]

Originally posted by JOEX
Depends on the color of the smoke and when it's smoking.


mine was smoking when i got on the gas only and it needed rerung. whens it smoke the most?

[anabolicsman]

it only smokes when i hit the gas! the guy said the rings were flat or something like then then i said how much to fix it then he said well the whole top end needs rebuilt so 850

[xc_racer1]

damn. dont take that. thats a ripoff. im gettin mine ported and polished high compression piston. rerung and a hot cam put in for 350

[JOEX]

Originally posted by anabolicsman
it only smokes when i hit the gas! the guy said the rings were flat or something like then then i said how much to fix it then he said well the whole top end needs rebuilt so 850
Seems kinda steep to me but I haven't priced any shop work in awhile.

Did they say what was included in the 'whole top end rebuild'?

[bens250ex]

mine smokes coming off the gas and then giving it a little gas. it puts out blue smoke. i have a 440 kit on the way but im wanderin if it has anything to do with the valvs?

[86 Quad R]

could be the stem seals if smoking when coming off the gas. :confused: