WHAT IS IT? A new plastic replacement part from Acerbis used by Colton Haaker, as well as Kawasaki’s offroad race team.


CONTACT? or (800) 659-1440.

Here’s a list of things that stand out with the Acerbis YZ450F chain guide.

(1) Design. The Acerbis chain guide is made of PA6 nylon material. It’s designed to withstand abuse from the chain and not bend or break in a collision. The nylon material was also selected because of its smooth texture. Less friction means less wear and slightly less drag on the engine.

(2) Installation.
The Acerbis chain guide comes in two pieces, so you don’t have to break the chain to install it. The chain guide has a lot of metal hardware, including bolts, washers and seats. The recessed seats spread out the load in a collision and make the nylon chain guide stronger than the aluminum stocker.

(3) Weight. Chain guides are a necessary evil. They keep the chain from derailing, but offer nothing from a performance standpoint. Sitting out on the end of the swingarm, the chain guide’s weight is unsprung, and unsprung weight fights the bike over every bump and ripple on the track. Including hardware, the YZ450F stocker weighed 9 ounces, while the Acerbis weighed 9.9 ounces. That extra ounce isn’t a critical factor for most riders.

(4) Durability. After a few weeks of riding with the OEM guide, you can tell it’s starting to lose the fight. After a couple months on the Acerbis unit, it looks eager to go a few more rounds.

(5) Looks. Some aftermarket plastic chain guides look like bulky Baja parts. Motocross racers are fans of functionality, but they don’t want to bolt ugly parts onto their sleek race bikes. The Acerbis chain guide looks good on the bike because the black color is understated. Acerbis offers chain guides for Honda, Suzuki, Kawasaki and Yamaha, but only in black.

(6) Noise. In the pits, we noticed more noise when the chain clacked against the hard nylon Acerbis chain guide, but we didn’t notice it on the track (probably because the YZ450F’s airbox noise drowned it out).

(7) Dirt clogging.
The Acerbis chain guide has a few nooks and crannies, but we didn’t notice any more mud collection than with the stock guide.
We have two points of concern: (1) It’s an ounce heavier. This isn’t nearly enough to feel on the track. (2) We had a crack form at the weld of the chain guide mounting tabs on our 2010 YZ450F. We think it was caused by a collision, but over the last year we have seen other YZ450Fs with similar cracks. Sadly, a stronger aftermarket unit might place more stress on the swingarm mount in a collision.

This is a good product, and when it comes time to replace your stock chain guide pad, it’s a worthy option. Acerbis’ plastic chain guide doesn’t have all the bells and whistles, but it keeps on going.

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