⚠️ C0R$A R3BU¡LD ⚠️

Trying to get your Spree/Elite to run, or run better? Post your questions here.

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ghost_EJ9
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⚠️ C0R$A R3BU¡LD ⚠️

Post by ghost_EJ9 » Fri Nov 02, 2018 10:50 am

What's up guys..

I got a 72cc Polini Corsa Bore on my SYM dd50 motor installed about 17 months now. I got a 28mm carb, minor ports, aftermarket exhaust and variator....you know, the usual.

Well I took off the bore tonight to check on it after just riding hard and doing a lot of racing these past few months, which means WOT. My temperatures been about 290 degrees when cruising and gets up to about 370 degrees when pushing it and I know it would keep rising if I don't ease off...we all hit about 60-80 mph when racing.

The top of the piston feels gritty. There's a big spot on the top of the piston, and the rest looks normal.

The sides of the piston has 2 spots where there are scratches. One spoke is about 1.5 inch wide and almost all the way up and down. The second spot is right by the connecting hole, about 1 inch up and down..

The rings seem alright. One is pretty loose and the other seems tight to where I can't rotate it..

The walls on the bore has horizontal scratches on it but doesn't look too bad.

I am planning to clean everything up and reinstall this bore and run it until it dies on me....I am on a budget here, I would wanna get a brand new bore but my funds don't allow it.

What would you guys do in this situation? Let me know!! I don't know why it won't let me upload a picture but I have a lot I can share with you. LMK...Positive and negative comments welcomed, anything is appreciated.

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Meatball
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Re: ⚠️ C0R$A R3BU¡LD ⚠️

Post by Meatball » Fri Nov 02, 2018 4:18 pm

Lemmie guess, the scratches are on the exhaust port side? Fatten up your pilot a click or two until the temps at wot get under control. Even if your idle isnt ideal, thats ok. Youre tuning it for full bore madness rather than perfect idle.

The Corsa is one badazz creation in many aspects. Aggressive timing and tight tolerances make it a true race bore. As with all “race” components, they are built for speed but not long life. Even NASCAR rebuilds a motor after every race because its “used up” afterwards. I have one Corsa build with about 3000mi and even a couple soft seizes on it...still runs like day 1. The bore certainly shows its’ battle wounds but compression tests say its fine. Ive read reports of people with well over 5000mi on their Corsa and still going strong. Im sure a long lifespan is the result of a proper tune and keeping temps in the safe zone.

That being said, I suggest you run it till she pops and start saving your money for a fresh Corsa purchase. You probably knew going in that it wouldnt last forever. When it finally dies be sure to give it proper burial, say a few words and reminisce about all the fun miles youve shared.
I need to find some new haters...the ones I have are starting to like me.

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Re: ⚠️ C0R$A R3BU¡LD ⚠️

Post by ghost_EJ9 » Sun Nov 04, 2018 8:00 am

Meatball wrote:
Fri Nov 02, 2018 4:18 pm
Lemmie guess, the scratches are on the exhaust port side? Fatten up your pilot a click or two until the temps at wot get under control. Even if your idle isnt ideal, thats ok. Youre tuning it for full bore madness rather than perfect idle.

The Corsa is one badazz creation in many aspects. Aggressive timing and tight tolerances make it a true race bore. As with all “race” components, they are built for speed but not long life. Even NASCAR rebuilds a motor after every race because its “used up” afterwards. I have one Corsa build with about 3000mi and even a couple soft seizes on it...still runs like day 1. The bore certainly shows its’ battle wounds but compression tests say its fine. Ive read reports of people with well over 5000mi on their Corsa and still going strong. Im sure a long lifespan is the result of a proper tune and keeping temps in the safe zone.

That being said, I suggest you run it till she pops and start saving your money for a fresh Corsa purchase. You probably knew going in that it wouldnt last forever. When it finally dies be sure to give it proper burial, say a few words and reminisce about all the fun miles youve shared.
Okay so I ended up buying just the piston and rings... after installation, it makes the ring rattle noise :/

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Re: ⚠️ C0R$A R3BU¡LD ⚠️

Post by Meatball » Sun Nov 04, 2018 3:19 pm

:roll:
I need to find some new haters...the ones I have are starting to like me.

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Re: ⚠️ C0R$A R3BU¡LD ⚠️

Post by ghost_EJ9 » Mon Nov 05, 2018 2:58 am

Meatball wrote:
Sun Nov 04, 2018 3:19 pm
:roll:
Now I have ring rattle 🤯 I guess imma just save up for a new bore and port myself. One way to learn is to do it hahahahha

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