Kdx cylinder damage and crank bearing play (time for some intervention)

[JZ05220r]

As the title states my engine needs quite a bit of work. Ran maxima premium 2 for an hour and saw some serious aluminum transfer on my cylinder in several spots. The worst was toward the exhaust port. This was after having Millenium replate the cylinder. They sent it back with a Wossner C piston which is the last biggest size before having to have the cylinder bored, (I asked for a pro x cast piston on the phone and on the form). Makes me question if the piston was not sized correctly. I ran some pretty rich jetting (45-48 pilot 1173 3rd and 155-158 main at 40:1 maxima premium 2). Warmed it up very thoroughly. Trying to figure out the cause of that. I thought I was running pretty safe jetting and was easy enough on the engine. What does it sound like I could’ve done wrong to you guys spit doesn’t happen this time again? Thanks

[SS109]

I suspect you might be correct about an incorrect piston. If I asked Millenium for a ProX, and they gave me Wossner, I would have stopped right there and called them. I would have gotten down to the bottom of what was going and why it was a C piston instead of an A. That is only thing I can see from your post that you could have done better. Never assume ANY company has done the work right. If there is ever any doubt then find out for sure.

[JZ05220r]

I suspect you might be correct about an incorrect piston. If I asked Millenium for a ProX, and they gave me Wossner, I would have stopped right there and called them. I would have gotten down to the bottom of what was going and why it was a C piston instead of an A. That is only thing I can see from your post that you could have done better. Never assume ANY company has done the work right. If there is ever any doubt then find out for sure.

Yea, I guess I screwed up there. After I informed them about their mistake and added how it was a C wossner and I won’t have any options to upsize once the clearance gets excessive, they basically told me “Sorry, just spend another 600 dollars to replate it again when the time comes”.

[SS109]

If you have documentation of what you requested, and proof of what you got, I would threaten them with taking them to Small Claims court because that means they screwed up and are legally liable.

[John_S]

Are there any paperwork specs from MT on the exact size of the cylinder after the replate? You could then get Wossner C piston specs and go from there with them to see if it was sized exactly as it should've been. I've never heard of a replate needing a C piston. It should've been back to factory spec when you got it back with the ProX piston you asked for. I'm sorry to hear about all of this.

[Molly's 70]

I'd send the cylinder & piston back to Millenium and ask them what they think. You'll probably have to pay the price again, but who knows, maybe they will work with you.

When you get your cylinder & piston back, take it to a machine shop & have it measured professionally.

[JZ05220r]

I'd send the cylinder & piston back to Millenium and ask them what they think. You'll probably have to pay the price again, but who knows, maybe they will work with you.

When you get your cylinder & piston back, take it to a machine shop & have it measured professionally.

I ended up getting in contact with the R&D manager at millennium. He graciously agreed to replate the piston at no cost, really nice guy I will say. Fast-forward to today, the sales guy called and told me they must’ve not checked the piston cylinder clearance when supplying the piston and that was the cause of my problem. I mentioned they gave me a size C wossner. They checked the ring gap and everything was within spec unlike their assumption that I didn’t check it. The kicker is that I have to pay for a new piston. While on the phone I pressed them twice about that being BS but wasn’t getting anywhere and they “don’t cover parts”. However, I am outside the warranty period. At least I won’t have to pay for shipping and they will discount me on the piston. It is what it is. Just wanted to update this. Thanks

[Chuck78]

I ended up getting in contact with the R&D manager at millennium. He graciously agreed to replate the piston at no cost, really nice guy I will say.

... today, the sales guy called and told me they must’ve not checked the piston cylinder clearance when supplying the piston and that was the cause of my problem.

I mentioned they gave me a size C wossner.

The kicker is that I have to pay for a new piston.

While on the phone I pressed them twice about that being BS but wasn’t getting anywhere and they “don’t cover parts”

I would argue profusely that they AREN'T COVERING PARTS when giving you another piston, they are covering LABOR, as the technician/employee who honed tue cylinder and spec'd & provided the piston made a huge labor mistake...

Darnit that's unsettling... Millenium has had ups and downs, and does a lot better than PowerSeal at the inspection and technical work, but this type of treatment is ridiculous for a company of it's size. PowerSeal does a great job of the actual plating process, but not so good at cylinder inspection and advising of port corrections needing made of OEM factory deficiencies etc, and have made some oversightsvon cylinder repairs which I've witnessed...

[kdxdazz]

Interesting story, even the so called best guys get it wrong, I know how you feel as I went through the same **** with 2 sleeve installs and the sleeve dropped as not installed correctly
We will see lots more bad work across all areas, companies are limited by the quality of tradesmen they can hire, tradesman are getting worse and shitty work gets put out the door, I cringe at the quality of welding at many places I've worked for but bosses can't fire them as nobody to replace them
Sending a forged piston when you asked for cast is a major oversight
Glad you got to the bottom of it

[JZ05220r]

Interesting story, even the so called best guys get it wrong, I know how you feel as I went through the same **** with 2 sleeve installs and the sleeve dropped as not installed correctly
We will see lots more bad work across all areas, companies are limited by the quality of tradesmen they can hire, tradesman are getting worse and shitty work gets put out the door, I cringe at the quality of welding at many places I've worked for but bosses can't fire them as nobody to replace them
Sending a forged piston when you asked for cast is a major oversight
Glad you got to the bottom of it

I feel relieved for the most part. I agree

[JZ05220r]

I ended up getting in contact with the R&D manager at millennium. He graciously agreed to replate the piston at no cost, really nice guy I will say.

... today, the sales guy called and told me they must’ve not checked the piston cylinder clearance when supplying the piston and that was the cause of my problem.

I mentioned they gave me a size C wossner.

The kicker is that I have to pay for a new piston.

While on the phone I pressed them twice about that being BS but wasn’t getting anywhere and they “don’t cover parts”

I would argue profusely that they AREN'T COVERING PARTS when giving you another piston, they are covering LABOR, as the technician/employee who honed tue cylinder and spec'd & provided the piston made a huge labor mistake...

Darnit that's unsettling... Millenium has had ups and downs, and does a lot better than PowerSeal at the inspection and technical work, but this type of treatment is ridiculous for a company of it's size. PowerSeal does a great job of the actual plating process, but not so good at cylinder inspection and advising of port corrections needing made of OEM factory deficiencies etc, and have made some oversightsvon cylinder repairs which I've witnessed...

After the second time asking why the heck I have to replace the piston with my own money, it was either give up (like I did) or potentially get on their nerves. I sometimes (unrealistically) worry that people will go out of their way to create more issues if I hit the right nerve. But yea, you hate to see it. Also wanted to add that this thread has become alittle full of drama. So I apologize if this is lacking most of the positivity that kdxrider.net deserves.

[JZ05220r]

I ended up getting in contact with the R&D manager at millennium. He graciously agreed to replate the piston at no cost, really nice guy I will say.

... today, the sales guy called and told me they must’ve not checked the piston cylinder clearance when supplying the piston and that was the cause of my problem.

I mentioned they gave me a size C wossner.

The kicker is that I have to pay for a new piston.

While on the phone I pressed them twice about that being BS but wasn’t getting anywhere and they “don’t cover parts”

I would argue profusely that they AREN'T COVERING PARTS when giving you another piston, they are covering LABOR, as the technician/employee who honed tue cylinder and spec'd & provided the piston made a huge labor mistake...

Darnit that's unsettling... Millenium has had ups and downs, and does a lot better than PowerSeal at the inspection and technical work, but this type of treatment is ridiculous for a company of it's size. PowerSeal does a great job of the actual plating process, but not so good at cylinder inspection and advising of port corrections needing made of OEM factory deficiencies etc, and have made some oversightsvon cylinder repairs which I've witnessed...

After the second time asking why the heck I have to replace the piston with my own money, it was either give up (like I did) or potentially get on their nerves. I sometimes (unrealistically) worry that people will go out of their way to create more issues if I hit the right nerve. But yea, you hate to see it. Also wanted to add that this thread has become alittle full of drama. So I apologize I that this is lacking most of the positivity that kdxrider.net deserves.

[KDXGarage]

Hey, not your fault. No drama noted from me.

[billie_morini]

ditto

[Chuck78]

PowerSeal was looking like my more favorable option again, but I think I'll sway either to Millenium still, or else send my cylinder to Boyko Racing or Tom Morgan Racing for port cleanup and port chamfereing and deburring beforehand and then PowerSeal would be a perfectly fine choice on just the plating work... Some poor work is being reported from PowerSeal similar to what I've seen and experienced for many years now.

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[kdxdazz]

That's some disgusting deburring, I can do better with a needle file

[Chuck78]

I think the original poster and I both have realized that we may be best off going through a small time professional engine builder for cylinder plating, as they will do more well scrutinized and careful chamferring, deburring, and general inspection of the cylinder condition before sending it off to be plated by the companies who we would otherwise just send our cylinders directly to. I was less than pleased with all the above mentioned work steps after getting my Powerseal cylinder back, although not as bad as the guy in the screenshots