MXA TEAM TESTED: TWIN AIR RADIATOR SLEEVES

WHAT IS IT? Twin Air radiator sleeves are used to keep mud and debris from blocking much-needed air to your bike’s radiators.

WHAT’S IT COST? $44.95.

CONTACT? www.twinair.com or (800) 749-2890.

WHAT STANDS OUT? Here’s a list of things that stand out with the Twin Air KTM radiator sleeves.

(1) Concept. Back in the golden oldie days, when two-strokes roamed the earth at will, savvy two-stroke riders would attach a section of wire mesh across the downtubes of their bikes to knock down mud before it could clog the fins of their air-cooled engines. The mud would stick to the wire mesh and then vibrate off. Twin Air obviously has some old moto soldiers in its design department, because that is exactly what Twin Air radiator sleeves do—except for radiators instead of cylinder fins.

(2) Mounting. The Twin Air radiator sleeves are easy to mount. On a KTM 450SXF, the drill is simple: First, remove the four bolts from the radiator louvers and slide the Twin Air sleeves over the louvers. Second, align the pre-punched holes in the sleeves with the stock bolt holes before reinstalling the louvers. Third, when mounting the louvers back on your bike, hand-tighten all the bolts a few threads so that the soft material of the Twin Air sleeves does not bunch up around the bolts when they are tightened. Once all the bolts and sleeves are in place, tighten the louver bolts.

(3) Performance. The radiator sleeves did not disappoint. They held up well under all the conditions we threw at them. Not only did they help keep debris and mud out of the radiators, they also made for easy cleanup at the races. There was no need to pick at the radiator louvers or scrape for mud, which could potentially damage the radiator fins. After long test days in the hot sun, we did not lose any coolant due to the bike overheating with them installed. We rode with the sleeves on our test bikes for four months. At the end of the test, the radiator fins were in great shape. They didn’t have any of the normal dents and bent-over fins. On a side note, if you own a Honda CRF450 and race, you should invest in Twin Air radiator sleeves, because we destroyed both CRF450 radiators when roost went past the Honda radiator guard louvers and closed off the finning.

(4) Appearance. Since the radiators are hidden behind the side shrouds, the Twin Air radiator sleeves didn’t hurt the cosmetic appeal of the bike.

(5) Durability. Twin Air radiator sleeves have been tested on the almost-always-muddy European Grand Prix circuit since 2014. As for the MXA wrecking crew, our SoCal home base isn’t known for its rainfall; however, we spend several days a week testing at seriously over-watered tracks and occasionally find actual mud during our rainy season. During our test period with the Twin Air radiator sleeves, we went looking for mud wherever we could find it and made lots of riders around us angry with our penchant for hitting every mud hole on the track.

(6) Material. We had no issues with the spun-glass yarn material that Twin Air uses. Did you think they would use chicken wire like back in 1974? The Twin Air radiator sleeves are made from a nylon-coated, glass yarn designed to shed mud and dirt before it builds up. You could jerry-rig pantyhose or wire mesh to save money, but it won’t work as well as the Twin Air product—or last as long. We put them on and forgot them for six months. Then replaced them because what rocks and roost does to your radiator, it can do to spun-glass yarn (only a lot cheaper to replace).

WHAT’S THE SQUAWK? Two quibbles: (1) The price is on the high side. (2) The color of the glass yarn became dull and faded over time.

MXA RATING: If your racing environment is rainy, muddy or over-watered, you will find the Twin Air radiator sleeves invaluable. Radiators only work if air flows through them. Twin Air can make that happen in the worst of conditions.