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I thought I'd chime in 5 months later.

So David from DHM said the 'BLACK' ring is top and 'SLIVER' is bottom. CJR said 'SLIVER' is top and 'BLACK' is bottom. Weird they're opposites since I assumed they came from the same manufacture. If you're doing the install I'd just make sure you contact either vendors you bought from for more info.

Onto the break in period and ride feel...
After the install I started up the engine 3 times on idle prior to riding. 1st initial warm up (no revs 3-5mins) 2nd start up (revs to 3-4k rpm) 3rd start up (revved to 5-6k and let it sit till 100 degrees+).

The first initial ride to 100 miles consisted of 1/4th - 2/4th varied throttle to set the piston rings in. I never loaded the engine at low RPMs. After 100 miles, I varied the throttle 3/4th - WOT. The bike definitely feels like it has more pep in the low end. I hit around 71 mph for a top speed run, though I could have hit a few more mphs. Standing up riding averaging around 60-65 mph. I have about 400+ miles on the piston, and overall I think its worth the money.
I'm gonna be soooooo pissed if this is the case. I was told by David from dhm the silver ring is TOP,
And the black ring is bottom.
 

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Discussion Starter · #23 ·
I'm gonna be soooooo pissed if this is the case. I was told by David from dhm the silver ring is TOP,
And the black ring is bottom.
So who is right? lol...

I've ridden my bike about 400+ miles since install and nothing seems off. Still plenty of power.
 

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So who is right? lol...

I've ridden my bike about 400+ miles since install and nothing seems off. Still plenty of power.
I double checked my email to find the response, and I can confirm the silver ring is on top. Any chance you have a screenshot to confirm yours?
 

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I double checked my email to find the response, and I can confirm the silver ring is on top. Any chance you have a screenshot to confirm yours?
Below's the email he sent me.

I doubt David would have gotten them mixed up(I hope he didn't...) I swapped out my old piston back in December 2020. My only assumption is different batch? When did you do the piston swap?

Anyone know David personally? I hope he didn't [email protected]* me over lol..

90143
 

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Below's the email he sent me.

I doubt David would have gotten them mixed up(I hope he didn't...) I swapped out my old piston back in December 2020. My only assumption is different batch? When did you do the piston swap?

Anyone know David personally? I hope he didn't [email protected]* me over lol..

View attachment 90143
Well, one thing is for certain: one of us got screwed over. I suggest you email him back and find out asap,
90144
 

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Fresh HC piston install over the weekend on mine, silver ring on top after setting gaps (instincts told me the black ring felt more fragile than the silver one, so with the added heat the top ring takes it would be better served to have the stronger feeling ring on top). Time will tell, but it feels pretty good so far. Definitely need to retune now (worse part about a stand alone ECU w/o auto-tune), it feels rich from 2500 to about 3500ish rpm. Not real sure of how it feels up top yet but the lower end to mid throttle torque is very noticeable.
 

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FWIW takegawa big bore ring kit and kitaco neo ring kits both have the silver/white ring on top. Silver/white ring is a much harder material designed to handle the heat and maintain compression compared to the second ring (which is black) which serves to scrape oil from the cylinder walls and scavenge a bit of upper ring blow by compression.

Whichever ring was easy to file down is the lower ring. It is a softer material.

If you installed the rings in reverse, get new rings and fix it right away. You are harming your engine with blow by. It will run, but not a good setup.

 
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