Your cart is empty.
Your cart is empty.These kits are used on Eton, Polaris and Alpha Sports models with a 90cc 2-stroke engine. This is an upgrade that can only be used on the 90cc units. They are not adaptable to any of the smaller 50cc & 70cc 2-stroke units.
Dan & Erin
Reviewed in the United States on February 28, 2025
Cylinder head gasket doesn't seal well due to a small matting surface. Otherwise it went on easy and works
Big papa
Reviewed in the United States on July 5, 2024
Cylinder sleeve was cracked piston did not fit in the cylinder very disappointing.
Emily Moon
Reviewed in the United States on July 25, 2024
I put this on my son’s Polaris predator 90 after he blew the top end in November 2023, it is now almost August 2024 and this thing is still a beast! It totally woke this four wheeler up and increased bottom end power by a substantial amount. I’m an average mechanic but have never done this before and it took me about 30 minutes and a 6 pack of beer. Fired right up and even us 250lb adults can absolutely RIP on it! We’ve gotten well over 30-40 hours on it since and it’s still rippin! Hasn’t lost a single bit of compression! Going to order another just as backup since we all know we can only expect so much out of a 2 stroke top end, especially when you beat on them like we do. I HIGHLY recommend this kit along with everyone else that has seen this fourwheeler in action since installing this big bore kit.
Tristan Davis
Reviewed in the United States on March 24, 2024
Everything about it is junk cylinder was broke when It arrived rings didn't fit in ringland in piston cheap china junk waist of $130
JCW
Reviewed in the United States on September 22, 2023
I was optimistic and this was so easy to install on our 03 Polaris predator 90, it took 45min the bike has a lot more power and everything went together perfect I highly recommend this big bore kit to anyone. This was the first motor I have rebuilt and not the last!
Brandon
Reviewed in the United States on August 10, 2023
I ordered it for a eton viper 90 and the cylinder won't fit in the crank case I swear nothing fix's I ordered on here
Matt
Reviewed in the United States on November 15, 2022
Perfect replacement for the stock top end. Not a 100 mL kit like they say but was very very nice quality compared to the factory. It was nice to get all the parts to replace everything that was hard and brittle. Unit now runs perfectly smooth thanks for the great deal
Dave Stevenson
Reviewed in the United States on October 18, 2022
I bought this big bore kit for a 2003 Polaris sportsman 90cc, very good quality and worked well on the Polaris
Recommended Products
$136.95
$ 57 .99 $57.99