Mayhem Engineering has been making high-quality rock crawling rims for years, and the Ultimate Comp Wheel is their latest offering. The Ultimate Comp Wheels feature aluminum construction and center supports that prevent the foam inside the wheel from moving laterally. By doing this, side-hilling and tire support should be drastically improved as well as the ability to drive up undercuts in rock faces. Let’s take a look.
First off, the machining quality is superb. The rims are packaged well and include everything you need to mount the new wheels. The kit includes four machined rims, four black Delrin rings, four machined rings and 12 wheel supports. Mayhem sent us both the 5/8” and ½” supports, so we can test the different heights of the center ring.
I installed RC4WD’s X-Lock tires onto my rims. They are very soft tires that hook up to rocks well and feature a tall, aggressive stance. They work decent in stock form, but I knew with Pro-Line memory foam and better sidewall support, they could really shine. The center ring of the rims is what supports the foam and prevents the tire from moving side to side. I installed the memory foam after cutting a small channel in the inside center to make room for the ring. I did this by completely turning the memory foam inside out and slowly using very sharp scissors to make a notch. I took my time and installed the foams in the tires and then onto the ring. I made sure that the foam was fully seated before I mounted the outside rings of the rim. They went together easily, and the bead held strong. I cut two small holes in my tires to allow air to escape and tested the “feel” of the tires.
I installed the rims on my newly built “shafty” rig that was featured in RC Rock Crawler magazine and started crawling around. Forward traction was incredible, and confirmed that these tires were good. I started side-hilling to see whether the rims offered any substantial increase in performance. After going through just one pack, I noticed a big difference. The tires were definitely more stable, not only on side-hilling but also on squirrelly climbs. The tires were planted and very stable—they definitely helped. I then attempted a few rock faces that had undercuts in them. On the smaller ones I was able to push my truck up to hard and get the tires to bite and overcome the obstacle. That was pretty awesome, as in the past my tires would go all the way down to the rim and not grab. The ring definitely helped.
All in all, these wheels are awesome. They held a strong bead and increased my rig’s performance. I like that they are very tunable. To change weight, you can swap aluminum or Delrin rings on the rim, or you can run the tall or short center rings. This will also affect how much stability you gain in your tire. These tires worked awesome with the RC4WD X-Lock tires, and I can’t wait to try them with some other 5.5-inch tires that I regularly use in competition.