Yeah, I know it's a no-go too. And yes we just completely rebuilt this engine.
It was running, but not great, since the rebuild. Was sputtering on acceleration after the rebuild, much like my YZ is doing.
It has a full FMF system, and according to them it needs a 122 MJ, so that is what I put in ($12.53). I also installed a 48 PJ since I read that the PJ still adds fuel to the entire throttle range, and I figured it was rich (and the plug showed this).
So I dropped the needle one position.
Then my son rode it and said it felt better on the accel. But since he's 11 and inexperienced, I didn't know exactly what that meant, and I took it out for the final killing ride.
I think I am getting conflicting and/or bad information right now and I dont know what to do with it all. The manual I have tells me incomplete info I think.
I can share that info, but I'm feeling a bit defeated right now and want to give it a rest for a couple days.
The only light at the end of my tunnel right now is that I didn't melt down 2 bikes yesterday since I put a smaller PJ in the YZ too (48), but it still stings.
As an aside - I am still questioning whether the melt-down occurred due to a jetting issue, or a cooling issue. When I took it apart last night I removed a plug from the water pump area to drain the coolant, and nothing came out. Plus, the guy at the local bike shop told me months ago (when I showed him my KX85 cylinder) that a burnout at the exhaust port side usually means a cooling problem. But I dont know that, or can verify that, but it makes me wonder.
I'm just disgusted with myself at the moment, but have been thinking about it since.
It was running, but not great, since the rebuild. Was sputtering on acceleration after the rebuild, much like my YZ is doing.
It has a full FMF system, and according to them it needs a 122 MJ, so that is what I put in ($12.53). I also installed a 48 PJ since I read that the PJ still adds fuel to the entire throttle range, and I figured it was rich (and the plug showed this).
So I dropped the needle one position.
Then my son rode it and said it felt better on the accel. But since he's 11 and inexperienced, I didn't know exactly what that meant, and I took it out for the final killing ride.
I think I am getting conflicting and/or bad information right now and I dont know what to do with it all. The manual I have tells me incomplete info I think.
I can share that info, but I'm feeling a bit defeated right now and want to give it a rest for a couple days.
The only light at the end of my tunnel right now is that I didn't melt down 2 bikes yesterday since I put a smaller PJ in the YZ too (48), but it still stings.
As an aside - I am still questioning whether the melt-down occurred due to a jetting issue, or a cooling issue. When I took it apart last night I removed a plug from the water pump area to drain the coolant, and nothing came out. Plus, the guy at the local bike shop told me months ago (when I showed him my KX85 cylinder) that a burnout at the exhaust port side usually means a cooling problem. But I dont know that, or can verify that, but it makes me wonder.
I'm just disgusted with myself at the moment, but have been thinking about it since.
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You HAVE been getting conflicting information.
Did it seize? Is there similar damage on the piston? What was the installed Piston to Cylinder clearance?
I like to let it be for a few days and come back with fresh eyes. When you own enough bikes, chances are you'll hit severely unlucky streaks. I think I am just recovering from one of mine. Probably threw $2000 at the garage recently...
-BIG DAN
Did it seize? Is there similar damage on the piston? What was the installed Piston to Cylinder clearance?
I like to let it be for a few days and come back with fresh eyes. When you own enough bikes, chances are you'll hit severely unlucky streaks. I think I am just recovering from one of mine. Probably threw $2000 at the garage recently...
-BIG DAN
It's not seized.
I am going to take a break right now, a step back.
It's Saturday night and I am going to forget about it all for the rest of the weekend, and go have a movie night with the bambino. It's his bike I broke so I'm going to try to make that better, and since he was so excited to go to the MX park today but was denied, I'm going to go hangout, watch movies, play Playstation, whatever he wants, probably be up til 3am.
Whatever it takes. De-compress time for me too.
Bikes aren't everything right?
I'll be back later.
I dont recall right now. I know I posted specs earlier in this thread though.
Yes, the piston is shot.
I am going to take a break right now, a step back.
It's Saturday night and I am going to forget about it all for the rest of the weekend, and go have a movie night with the bambino. It's his bike I broke so I'm going to try to make that better, and since he was so excited to go to the MX park today but was denied, I'm going to go hangout, watch movies, play Playstation, whatever he wants, probably be up til 3am.
Whatever it takes. De-compress time for me too.
Bikes aren't everything right?
I'll be back later.
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Sucks man.
We have all been there and done that.
We have all been there and done that.
Yep, I know you have. Thanks.
This is a stepping stone.
I'm all good. I learned a bunch; I think most importantly the sound of an engine, as it goes from bad main bearings, to rebuild, to start-up, to top-end melt down. It completes the cycle.
And it's just money right? They'll print more.
What do you mean nothing came out?
Where did the coolant go?
You've been around cars long enough to know that the coolant system needs to breath and be bled.
I've seen that type of damage before but because the exhaust side gets too hot due to lean jetting. Usually a coolant issue will leave eveidence all the way around a cylinder. Also there is an exhaust port bridge. I'm not sure if it applies to that model but wiseco asks that certain models have the skirt drilled to allow additional fuel to lubricate that bridge.
Take a break for a few days. Ca
Yeah if it was not overheating last week then probably not this week either.
I'm sure you ran it with the cap off to check circulation when you rebuilt it as well. Correct?
I'm curious as to why no coolant came out of the drain plug. Was the plug bone dry? Was the cap off when you pulled the plug? Is it possible there's a plugged up impeller or it broke? When you did the rebuild did you replace the impeller as well?