Four-stroke top end?

[thorns]

Im getting to that stage where I am starting to think about a top end rebuild on my 450. Realistically I think I should be fine for summer, but by that stage, it should be about time for a freshen up, will be around 80 hours I would estimate by this point. My plan is to start collecting the parts over the next few months as funds allow to have it all ready to go.

Couple of questions:

1 - If I was to do this myself, are there any particular tools I should buy to do this? I have the usual socket/spanners/T handles, and also have a good set of torque wrenches. Is there anything I should look into adding to this to make the job easier?

2 - If I was to pay a workshop to do this, how many hours labour approx. would be involved in this if its just a new piston and rings?

[barty5]

No real special tools required other than feeler guages to do shims but guessing you wont have a set of shims. Just as easy while head is of if you dont have to take in for a minimal cost to get shims done. If you dont have torque settings etc good chance they will be online somewhere. Only take a few hrs to do. Shop is likely to charge 4 - 5 hrs. Plus parts. You'll find parts online ebay or US shop way cheaper there are a number of them that will ship back to NZ, I use to do it a lot saved heaps.

[thorns]

Cheers Bart.

Yeah have been hunting round on line looking at prices, NZ is actually getting a bit more competitive it seems which is good, especially seeing as they sting you quite hard on anything over $400 these days.

Been watching a few youtube vids and doesn't look too hard to do if your methodical and think through what you are doing, so think I may give it a crack myself.
Going to check valve clearances in the next couple of weeks, so figure if that goes okay, it should be pretty straightforward doing a top end after that.

[scott411]

Cheers Bart.

Yeah have been hunting round on line looking at prices, NZ is actually getting a bit more competitive it seems which is good, especially seeing as they sting you quite hard on anything over $400 these days.

Been watching a few youtube vids and doesn't look too hard to do if your methodical and think through what you are doing, so think I may give it a crack myself.
Going to check valve clearances in the next couple of weeks, so figure if that goes okay, it should be pretty straightforward doing a top end after that.

not going to advise on how hard it is because i am not a mechanic,

have a look at genuine pricing as it is competitive in NZ, compared to good name aftermarket stuff, (vertex is my pick of the after market stuff)

80 hours is on teh lower end for a 450 for general use, even our top 15 NZ race guys were doing 50 hours easy on top ends on 450's, i have done over 100 myself, and know guys that have done over 200, i would say 100 hours is safe, but change the valve springs at the same time,

[WStain]

Do your cam chain while you are there. Get a flywheel puller for that.