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So, I think is probably bad....

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How many see the intake valve shading the piston?  How many know I am at TDC, cams at 10 and 2.  I think my pretty head may be phuct....

 

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You have the V/C off? And your saying the cams are at 10 and 2?
Then Lucy, we have a problem!
Does this run ?

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Well, I got a little time this morning and my friend Jim and I popped the head off of the DR-Z.  It was pretty quick work we were done with the tools cleaned up in 1.5 hours.  I also did a bad thing, I popped a keeper using the internet socket method.  We wore safety shields and glasses, two smacks and we were clean.  It was fun, but I wouldn't have tried it on a non-bent valve.

So, on to the carnage.

First we pulled the cams and the bucket of the destroyed Intake valve.  It appears the springs failed, then the valve became unattached and walked around.  We found all of the keeper and the pieces of the valve guide.  What I think saved most of the stuff was that it caught the exhaust valve and the engine shut off immediately, and the intake valve made minor contact, but didn't fall in because of the exhaust valve.  Lucky me.  Note, it does not have Ti retainers as I was told.  I will measure the valves later to see if they are stock or +1 mm on the intakes.

Anyway, on to the carnage....

Under the bucket view

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BOTH! Springs failed!

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Mr. Exhaust valve had a bad day as well...

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It is amazing it did not obliterate the motor.  Good thing I was at like 3k RPM.

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It does have APE spring seats.

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Piston was mildly abused, I think I am lucky there, that it isn't worse.  You can see the pieces of valve guide sitting on the piston...

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I think the head can be salvaged, it has almost a ding on the intake, but it is pretty shallow and might be fixable...:clap:

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I have no clue if I can use it, it looks to be almost into the seat 

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The cylinder isn't hurt, but I think I will replace it, the piston, the crank, all the lower end bearings and seals.  That way I will know what is in there.  If I can't use my head I will buy another one.  This one has my name engraved on it. 

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See on the right, my name is engraved

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I can't get the intake valve out because it is mushroomed so badly.  But I got the exhaust valve out and she is also a wee bit bent...

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Well, there you go, sad but not so sad.  I need to figure out what parts I need, I will miss the little bike until it is fixed.  I am going to make her a big bore again, I might even put in regular stage II cams and sell my big ones.  I am wondering if the springs were really right for those....

The current stage II cams both have 9.07 mm lift and 238.5 duration, with 107.5 Lobe Centers.

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Edited by TLRDoug
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It does look like you were relatively lucky. Your diagnosis and path to repair also appears sound.

I'd send the head off to FastHeads or BigBore Thumpers for an evaluation and cost. Even if the one seat is bad, they can replace it. I'd not force the damaged valve out, let the pro do it.

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What he said ^ , I'd simply replace the seat and start from scratch , at least one new guide and with valves , springs , keeper, retainers you'll be good with the head . Definitely got lucky on that one.

 

 

.

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If you ain't good, it is nice to be lucky.  So Fast heads.  Second person that has suggested that.  I had decided I can't get the valve out.  So maybe I will send her off to get new seats and valves and stuff.  Thanks again for the sound advice fellas.

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How many miles were on the motor? How much of the history do you know about it?

Back when modifying the DRZ's 4 wheel cousin for MX was the thing to do, they would swap out the LTZ's single valve spring for the DRZ's duals. Those boys would run alot bigger lift and duration than the 2003's.
I too am running the 2003 intake with a larger Web exhaust cam. This isn't the kind of post I want to read.

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I don't know what they are, I sent it to A.P.E. Big Bore Thumpers. Jeff who called me after I sent an email said, "I want to fix that head."  He thinks it will be no problem.  I am sure they seem to be good at what they do.  I am going to lay back and enjoy it.  Trying to decide what big bore kit to buy.  I think I have a Cylinder works, and they seem to be priced nicely so I will probably go with that.  I am not sure about the oil pump and such, but probably will do it as well.

 

I think A.P.E. uses Kibblewhite springs, so we shall see.

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