What about using brake fluid or possibly diesel to flush all the oil out so there is nothing for the debris to cling onto?

 

Blown head gasket. I posted before. The smallest valve closest to the gasket failure (exhaust,) less metal gets hotter before more metal (intake valve is larger.) Valve to valve guide tolerance is very tight. Too much heat in these areas will cause failure.

You'll learn so much if you do the case job youself J'. Take your time with a methodical approach and you'll do fine. The service manual for the 09 is on here somewhere, (I posted it recently, it'll do for the 06 as the engines are almost identical. If you must have the 06 manual PM me and i'll organise a pdf copy for ya.) Take plenty of digital photos for reference and take your time. I put some new mains in my RD125 when I was 16 with help from a manual. Bike ran great for more 10K miles, only died when the guy I sold it to t-boned a bus at 50 mph. Better to spend $200 on new shiny tool that you'll have for life than give the money to someone else. Engines are just lego for grown ups.

 

I'm sorry I think I misunderstood you. You think that the reason for all of this was a blown head gasket? What would have caused this? The head gasket was brand new with the 351 kit.

 

If I may: you ran the engine first without having the head torqued right. This is enough to weaken the head gasket. Even torquing it right afterward does not ensure integrity there. In retrospect, you should have changed it when you torqued the head anew.

 

I hate trying to diagnose things like this over the internet with jpeg images...pretty hard to do. On the head gasket issue, let's look at the pic from jhoff's first page post where the head gasket is still attached to the cylinder. I don't know if I'm seeing the classic symptoms in the gasket itself when a head gasket fails. You can usually see it clearly in the gasket itself since it's the weakest link in the chain of components. Now, I don't like that spot at the the 3 o'clock position in the first pic...like a little dent in the fire ring of the gasket. However, I don't see the classic combustion residue streaking out from the edges of the gasket like you often see. For a blown head gasket, this one looks awfully clean and intact. Even the material outside the fire ring looks pretty good. Like I said...internet pic diagnosis can be shaky, and I make no definitive judgements.

 

I wouldn't feel good about a cleaning only. who knows if there's metal chunks stuck in spockets or gears or whatever? That's just me though.
jhoffy - I bought a used bottom end off an 09 for about $450 and did the swap myself. I don't let anyone work on my bike because I want to be sure the work is done right
Plus I still have my old bottom end as spare parts

 

I agree you should spit the case just to be certain... do it right the first time or you might just have to pull it again + it'll just weigh on your mind otherwise...

I’m going to stop reading these Jhoffy threads... My 351 kit is on its way from Bill and these threads are making me kinda nervous.....

 

351 kit installed today and running perfectly......no pop/bang!

Johffy - Its called use a torque wrench mate - use one! The 46N/m head bolt tension is actually quite alot of force. My wrench is pretty long (can do 120 Nm) so can exert quite a bit of force. if I was just using my 1/4 inch drive by feel i would never go that tight, so it just shows you need the right tools. I'm not saying that people can go by feel, but they are still silly unless they know the engine very well. Oh and yes the wrench can be out if treated poorly, but at least it will be close enough...

Oh and just for ****s I set the cams up as per that mod and it was fine, but no real difference so went back to stock cam settings - rev to 10k ...again no BANG!.. just flawless. I have all valve clearances set about midway - Inlet 0.15mm and exhaust 0.22.

 

The staining on the cylinder is clearly visible as is the leaked oil/coolant/dirt that has gathered on the elbow on the cylinder.

J'. Many reasons why the gaskets go, who knows. But you can minimise the cahnce by torquing the head in the correct sequnce and in 2 stages ( as I described in an earlier post.)

I've had to replace more than one head gasket in the past, and my experience is thet they only blow on one side i.e. under, or above the gasket. One the gasket is damaged the weak spot is there and any further damage will be on that side of the gasket.

 

The piston is aluminum, no?

The gears are hardened steel in the gearbox right?

I would turn it upside down, flush it out and roll through the gears backwards a bunch upside down. Call it a day. Then i would put my stock jug and piston on, or find one. And that used head and ride a stock bike for a very long time.