Piston damage! What happened here?

[207wheelin]

269313
What do you suppose damaged this piston?
Dirt? Oil starvation? Something else?


My daughters 200s recently started making some funky noises at idle. I thought crank bearings but on teardown found that the Wiseco piston I installed a couple seasons ago was damaged as well as the cylinder. Plus there was a pretty good amount of metal in the oil which had been changed recently.
I'd appreciate your input as I'm going to rebuild it and would like to be sure I'm not overlooking something that will destroy this engine again in short order.

Many thanks
Corey

[ATC King]

The stock pistons are cast aluminum, the Wiseco pistons are forged aluminum.

Before I say anything else, it could be the piston to cylinder clearance wasn't correct from the start. Cast and forged pistons behave differently from cold to hot and that has to be taken into consideration. The Wiseco piston should have come with a specified clearance and/or it's available online with a part number search.

On to it, there's no need for a forged piston in a stock engine and because of their low silicon content they tend to not last as long as a cast piston.

With a forged piston, proper engine warm-up is more important. Just firing the thing up and taking off isn't a good idea.

There's a lot of variables but forged pistons can tend to rattle a bit until the engine is at operating temp. If they do, it's important to not load the engine much until it's fully warm.

The dirt and oil starvation thing you should be able to answer yourself. Oil starvation and the camshaft would go before the piston. Dirt...check the air filter.

[207wheelin]

Thanks ATC!

Air filter is good. Looking at the cam the bearing areas got scratched up too. I think it's from the metal that was circulating in the oil. I've oil starved a cam before and it was very discolored and blackened and this cam looks fine other than the bearing areas being scratched.

I'll dig in a little further tommorow.
Take care
Corey



I was warned about not letting the machine warm up before riding when I installed the piston and thinking about it now I should have just went with a cast piston. When this engine goes back together it'll have a Shindy piston in it.

[El Camexican]

The last time you had the engine apart, did you do any kind of cleaning, like bead blasting by any chance?

[oldskool83]

junk was in motor, dirt or something fell into plug hole. Motor prob was not fully torn down inspected and put back together. Dirty air filter or lack there of. We don't know what you did, might not of been your fault. Maybe you guys ride in swamp or sand? either way something got in there. Time do it all over again.

[ATC200X4716]

What does the cylinder look like? Do you have any means to measure the bore size to determine the piston clearance?

[207wheelin]

No bead blasting just a good scrub wish a wire brush and degreaser, when I replaced the top end I took four cylinders in to be measured for boring and was told to give it a light phone and use a STD piston. I never thought to tell him I would be using a forged piston.

There is also a pretty good chance it got a snort of muddy water. Sometimes our trails have some pretty good mud holes some nearly waste deep. I run an airbox and a filter but some of the holes are above the air intake and my daughter doesnt wheelie through em like the boys. These machines get beat pretty hard in a season and I'm still pretty impressed that the engine still ran with the damage it had.

My next plan is to completely disassemble the bottom end and send the crank in for service and start over. Plenty of time to get it back together before the season starts.
Thanks for the replies everyone
Corey

[rpeters]

From barnett

"If you have a sophisticated shop near you, you could have them "Plateau hone" the cylinder after boring. This will reduce break in time, and will also increase ring life providing the swamp water etc is kept out of the engine.

If you have te cylinder plateau honed, I would also use a non synthetic oil for break in for around 20 hours, then switch to a high quality synthetic like Mobil 20w50 V Twin oil if you ride in a hot climate, or if ride when it is from around 20 degrees to 50 degrees etc, you should use a lower viscosity oil, like Mobil 1 4T 10w40 etc."

[Scootertrash]

From barnett

"If you have a sophisticated shop near you, you could have them "Plateau hone" the cylinder after boring. This will reduce break in time, and will also increase ring life providing the swamp water etc is kept out of the engine.

If you have te cylinder plateau honed, I would also use a non synthetic oil for break in for around 20 hours, then switch to a high quality synthetic like Mobil 20w50 V Twin oil if you ride in a hot climate, or if ride when it is from around 20 degrees to 50 degrees etc, you should use a lower viscosity oil, like Mobil 1 4T 10w40 etc."



So now barnett is ghost posting or is rpeters his troll account?

[Scootertrash]

269313
What do you suppose damaged this piston?
Dirt? Oil starvation? Something else?


My daughters 200s recently started making some funky noises at idle. I thought crank bearings but on teardown found that the Wiseco piston I installed a couple seasons ago was damaged as well as the cylinder. Plus there was a pretty good amount of metal in the oil which had been changed recently.
I'd appreciate your input as I'm going to rebuild it and would like to be sure I'm not overlooking something that will destroy this engine again in short order.

Many thanks
Corey


I'm going with low battery voltage.......:shiftyeyes:

[207wheelin]

I'm going with low battery voltage.......:shiftyeyes:




Egads!!!! That's it!!! My friend thank you so much for helping me solve this, this, this, conundrum. And now onto my next battle....getting the power steering fixed!
Ahahahaha
��207

[ATC King]

It may be anecdotal, but I know of a couple vehicles that were completely sunk for extended periods, the engines full of water, and years later they don't smoke or burn oil.

The majority of damage I've seen if from a bad air filter or compromised air intake, like a leak/hole after the air filter. Hands down, those two things have destroyed more engines I've seen than anything short of running out of oil.

I've drowned a lot of my trikes over the years and even though I didn't totally swamp them, they ingested enough water to stall out. Maybe I run a bunch of junk that smokes and makes noise to start with, but they've endured that kind of abuse for years and continue to run.

The pistons possibly have barnacles on them, but I'm still riding.

[El Camexican]

So now barnett is ghost posting or is rpeters his troll account?

269398

I think it’s his online alter ego, You know, nice guy with an edit button lol!

[207wheelin]

Update. I located a complete bottom end and it arrived on Friday. Clutch side is complete and the recoil side is torn down. The rod is tight with very little side play. Going to start swapping parts over soon but really need to make a trip to the machine shop to have a couple cylinders bored.

Right now we are making maple syrup about 18hrs a day and with Spring on the way it's only going to get busier. Turkey season, ATV trails opening, fishing season, planting season, yep things are gonna be gettin busy round here.
Be well everyone
Corey

[rpeters]

269398

I think it’s his online alter ego, You know, nice guy with an edit button lol!

I didn't know this was a thread about barnett, but he has always been extremely nice and helpful to me and others that need help since I have known him.

[El Camexican]

I didn't know this was a thread about barnett, but he has always been extremely nice and helpful to me and others that need help since I have known him.

No doubt. Whenever Me, Myself and I hang out we get along fabulously.

[rpeters]

No doubt. Whenever Me, Myself and I hang out we get along fabulously.

From barnett

"Nice to know that you and scootertrash haven't improved yourselves one bit and are still still obsessed with me, and are still ruining other peoples threads with your negativity and childish comments. Keep up the great work of trying to impress yourselves, because contrary to your inflated narcissistic beliefs, there are few here that truly care what you think. :)


PS - I wonder if anyone ever got their money back from your good buddy oscar mayer that some of you guys were so in love with. :rolleyes:

I still have a 100% feedback on Ebay with glowing reviews from not only sellers, but also from buyers, many of whom bought items from me that cost over $5,000.00, so they would have readily left negative feedback if there were any problems whatsoever with what they bought from me. :Bounce"

[207wheelin]

Well. It's been real, and it's been nice....but it hasn't been Real Nice!