Top End Refresh

10 replies to this topic
  • Dp2boy

Posted August 12, 2007 - 05:31 PM


I tried to do a search but didn't seem to come up with an answer to my question: if I'm doing a complete top end refresh on an '06 what parts should I order ?

  • grayracer513

Posted August 12, 2007 - 05:49 PM


That depends. I'd say you'd need to tear it down and see what it needs first.

Is there any wear on the cylinder? Can you, or do you want to reuse the piston? have the valves shown any wear at all?

  • Dp2boy

Posted August 13, 2007 - 05:28 AM


I guess I'll wait until the thermometer drops below 100 here in Texas and then tear into the bike. I suspect the valves are good because the bike only has about 60 or so hours on it.

  • Dp2boy

Posted August 13, 2007 - 12:31 PM


OK, hypothetically if I wanted to have a completely fresh top end would I be looking at valves, springs, cam chain, tensioner, piston, rings ? I guess I might have to have somebody look at the valve seats too, huh ?

  • Kent Rathgeber

Posted August 13, 2007 - 03:03 PM


That parts list is only part of what you need. If you're replacing valves, you need valves, springs, valve seals, valve guides, and valve retainers (lotsa little parts). It's likely the valve seats will need to be recut or replaced for the new valves to seat properly. You'll also need piston, rings, circlips, wrist pin and bearing, cam chain (recommended, anyway), maybe the tensioner, and gasket kit (damn, that's a lotta stuff, ain't it?)

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  • Dp2boy

Posted August 13, 2007 - 07:59 PM


Yup, maybe too much for me, I'd better turn it over to somebody thats done one or two before.

  • grayracer513

Posted August 13, 2007 - 08:25 PM


If a valve job is needed, it should be done by a good specialized machinist who is familiar with YZF heads. If it isn't needed, then just replace the springs and seals.

If the bore shows any wear, it needs replating, or replacing. The rings are a given. The piston is reusable if you're not mostly racing with the bike, and it shows no significant wear at the skirt, the pin bore, and the ring grooves.

  • Yamaha4lyfe

Posted August 13, 2007 - 08:41 PM


60 hrs? and your thinking about doing a full top end rebuild? Wtf?

  • Dp2boy

Posted August 15, 2007 - 07:36 PM


Preventive maintenance my friend, preventive maintenance.

  • grayracer513

Posted August 15, 2007 - 07:49 PM


At 60 hrs, all you should need is rings, a cam chain, valve springs and seals. For perspective, my '03 has never been apart, nor needed a valve adjustment. It probably had 50 hours on it when I got it 3 years ago.

  • 450GN

Posted August 15, 2007 - 10:43 PM


yeah it seems a lil early to be doing all this but if you want to be safe... that is good too!

i must have tons of hours on my 04 that i bought new... i would think 100-150 hrs... and i have never done any maintenance... yeah i know i should and will do the timing chain and tensioner this winter but just saying... you are still way ahead of the game

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