This kit + stage 2 hot cam + head porting = awsome
- 7 Reviews
- 29 Questions
Unlock your bike's hidden potential with the power producing and durable Cylinder Works big bore kit.
O.E.M. appearing +1 mm to +4 mm big bore cylinder kit, a hand-matched, forged Vertex big bore piston and top-end gasket kit. These kits offer you an affordable way to increase horsepower and engine displacement without giving your secret away to your competition.
- Cylinder - New, not remanufactured, cast aluminum nickel silicon carbide (NSC) electroplated big bore cylinder that appears just like an O.E. cylinder. NSC is a composite of a nickel and silicon carbide, providing an excellent wear resistant surface with oil retention capabilities. Cylinders are then diamond honed to the exact bore dimension and proper surface finish to ensure the proper ring seal and oil retention.
- Vertex Big Bore Piston - To handle the internal pressures of a four-stroke engine, Vertex's big bore four-stroke pistons are forged from the highest quality 2618 aluminum alloy for superior strength and durability. Vertex uses unique piston profiles and compression ratios, offered in A, B, C and D sizes, to maximize power and performance while reducing blow-by and oil consumption. Each Vertex piston is then hand matched to fit each Cylinder Works cylinder perfectly.
- Gasket Kits - These kits contain the necessary gaskets to rebuild your top end. Kits include head, base, exhaust gaskets, and O-rings necessary when removing the cylinder and head during routine maintenance.
- Kit includes: Big bore cylinder, Vertex piston, piston rings, piston pin, circlips, gasket kit.
- Note: To achieve optimum performance, re-jet the carburetor with the available jet kits (sold separately) or a fuel-injection fuel management controller.
I own a motorsports repair shop,customer brought a TRX-450 in that needed a crankshaft and top-end. Thanks to Motosport we were able to rebuild the motor with better parts than stock and save some money at the same time. We have a test track here and before the customer picks up his machine we like to have him or her take a few laps. When they get off their machine and there is a smile from ear to ear you know they are pretty happy.This particular unit the customer was realy impressed. The big bore kit realy woke up the TRX. Thanks Motosport
works great easy installation everything was there
Purchased this kit for my 2006 YZ 250F and it took two tries to get a piston and ring combination that fit (rings would not fit in the grooves) finally sent me a piston that worked but it did not have the moly coating. Excellent power gains unfortunately it is on its 4th head gasket due to a poor alingment with the cylinder head allowing the gasket to hang over the combustion chamber. this was possibly the worst purchase I ever made and nobody is willing to stand behind the product, better off buying a Athena kit.
I installed this on my 06 yz450f it looks just like the OEM cylinder i did not install the piston instead i ordered a high compression piston. This bike runs like i added another 10 HP. I have been riding it for 3 months with no problems. hill climbing you can't run out of power. power is strong all the way through i would recommend this product.
Had some prblms with it.. to start off i have built over 15 yfz motors with no prblms so it wasn't me.. but back to the product. First problem I had was the piston pin clip came out and put a gouge in the cylinder so i went and got another cylinder and rings and clips and maybe had 10 hours on it and I broke a valve which went through my piston and as i tore it all apart again I also noticed that the inside of the cylinder had a crack in it. It could have been from the valve but i dont think so because the valve went through the piston and ive read about the cylinders cracking on other people too. so just thought I'd say if you wanna risk it go for it had lots of power but if you want something that will last i would go OEM. thats where I'm headed now.
Quality construction, made a huge difference in power. probably the most cost effective way to mod a 250f. I did have to rejet with a JD jet kit after i installed this; before it really ran to its potential. Was popping on decel and throttle response was not as crisp. after the bike was rejetted it is a monster.
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