Odd cylinder wear

[beamslayer]

Has anyone ever seen this before ?View attachment 225606

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Squish .050 mag side .055 pto side 150 psi checked with 2 different testers cold

 

[Setsaa]

Mine looked like that. Had a cracked sylinder skirt. Got a new cyl and pistons warrantied.

 

[BILTIT]

How many miles on it? I just pulled the head off my long rod with 300 miles on it and doesn't look like that, that's for sure. Looks like something is being burned in the combustion chamber than shouldn't be by the looks of the weird discolorations on the head.

 

[beamslayer]

Not many miles 300 or so since rebuild . It is weird still had good compression and ran good . Was just checking out my new bore scope and installing my oem pipe to go compare to the slp pipe . The rings are really pitted on the exhaust side .
Should have never bought the bore scope and just kept riding it.

 

[xc6rider]

tight ring gap??

 

[beamslayer]

Checked end gap before installing . Nikisil not hard enough ? The cylinders where reniked at 1500 miles when I installed kit .

 

[winter brew]

3rd picture down.....is that a tear/nic in the or ring at 12 o'clock position or am I seeing things? Probably nothing to do with the issue but didnt know if you noticed it.

 

[xc6rider]

How do the pistons look?

I'd also think lean on oil, or possible wash from coolant. Lean oil would be more likely of the two as a coolant wash would likely present in one cylinder...

 

[TRS]

Looks to be a ring issue. Flat spots? Would like to see pistons and the rest of the bore. What brand of pistons and who renicked.
Squish is pretty tight, IMO. In the head picture it shows the solder tracks, and it should be checked above the pin for accuracy.

 

[beamslayer]

pistons are wiseco from mtntk kit, millennium did the cylinders twice they forgot to weld them the first time

 

[TRS]

Jim,
When you pull the cylinder off, put the rings in each cylinder in the proper position. Take a flashlight and see if you can see light pass between the ring and the cylinder. I would bet the ring is not sealing in the area that still has the honing marks.

 

[beamslayer]

Thanks Tony I will . How is it going with the Gen 4 ?

 

[TRS]

Should be on the snow Sunday. New flash.
I have had this problem with wiseco rings before.

 

[die hard poo]

Looks to me like a cold seize. Wiseco pistons tend to have this issue. I know a friend of mine squeaked a couple mtn tek pistons on his dragon. They looked similar to this. He let it warm up to 125 before hitting the gas, but had to get on it pretty good out the hole. Shortly there after it seized...

 

[xc6rider]

Looks to me like a cold seize. Wiseco pistons tend to have this issue. I know a friend of mine squeaked a couple mtn tek pistons on his dragon. They looked similar to this. He let it warm up to 125 before hitting the gas, but had to get on it pretty good out the hole. Shortly there after it seized...

Once he gets the pistons out, they'll determine this possibility easily!

 

[AKSNOWRIDER]

I agree with diehard..looks like it was too tight, or piston expanded faster then the cylinder....what was your clearance set at?

 

[TRS]

Looks to me like a cold seize. Wiseco pistons tend to have this issue. I know a friend of mine squeaked a couple mtn tek pistons on his dragon. They looked similar to this. He let it warm up to 125 before hitting the gas, but had to get on it pretty good out the hole. Shortly there after it seized...

I would tend to agree with you, but Jim has 150# compression and said it still ran fine. Once the pistons are out it will be easier to diagnose.

 

[BILTIT]

Just want to send a shout out to WORKSUCKS for the BAD rating he gave me on my post in this thread, thanks buddy.

 

[Daltech]

Since it,s a replated cylinder, check the bore of it. I had a m1000 cylinder couple weeks ago that was done by millenium. Piston would go in from the top, but when it came below the ports it got stuck, without rings on the piston. So the bore was not correct on my cylinder.


Daltech

 

[geo]

More pics when you get it apart please.

What I see is too-tighta everything. 150 cranking, 50 thou (probably the ones over the pin) and asking for 4.5 thou clearance with a forged Wiesco piston.

Who's head? I had to deck my SLP domes to get to 58 thou. squish with this kit. I tried 55 last year and that was a bit tight below 5000' with my pump fuel. My cranking pressure is 135 at 1200' with the 12.7 combustion chambers and again tight until over 5000' with my motor.
If you do have 5 thou difference between cylinders for squish you should check why imo. Pistons, domes, rod bearing?