Topeak TSG-01 Digital Gauge

Big Ring Adventure Team

Ride. Research. Report.

Home | Go | Gear | Top10 | About | Mix | Search Results

Custom Search

Tip: Be sure to enable ActiveX for our site if you want to take full advantage of Google features. Results of your Google searches will appear on the Search Results page.

Key Search Terms: Topeak digital gauge, tire pressure gauge, Topeak TSG-01.

Please support our sponsors.
Big Ring Media Team, Inc. Impact! Creative technical writing and photography entertains as it explains to make your message stick. It's your story. Tell it well.	Weber Sports Serving cyclists, runners, swimmers, skateboarders, and others with the best gear and the latest information. For your active lifestyle.

Product: Topeak TSG-01 digital tire gauge. Battery: CR2032 x 1. Measurement Range: 0-255 psi; 0-17.6 bar; 0-18 kg./sq cm. Approx. Dimensions: 2.25 x 4 x 1 inches. Mass/Weight: 62 g/2.2 oz (Topeak Web site says 95 g; our measurements from our digital scale). Product Put in Service: No record; estimated mid-year 2006. Reviewed by: Rich Ries. Cost: MSRP not known; typical street/online price $18-$20. Recommended? Yes, with reservations.

Executive Summary: Unmatched accuracy but can be cumbersome to use.

Ratings

(1 is lowest, 5 is highest)

Comments

Ease of Use

Good on Schrader; can be too tight on presta; wish it had a bleed valve; fat head and short neck limit access

Cost/Value

If you fret about half-pound variations in pressure

Style

It's digital; we'd give it a 5 if the body were carbon fiber

Don't depend on your pump for accurate pressure readings. Pump gauges are estimates, at best. Their accuracy is further limited by parallax, which can be a problem with any analog gauge. (Parallax results in inaccuracy when your eye, the gauge's needle, and the scale of units aren't in perfect alignment.) For most riders and most applications it doesn't matter. If you're off by 5 psi on your road tires that's less than a 5 percent error if you want to run 110 psi. If you run 1.9 tube-type tires and 45 psi on the trail, 5 psi is an insignificant variance. But if you're off by 5 psi on your 2.3 tubeless MTB tires, that can be a 20 percent error assuming you normally use 25 psi. And variations of 5 psi one way or the other during suspension setup can seriously alter performance.

The Topeak TSG-01 digital pressure gauge solves that problem. I assume it's accurate, although I've never had it calibrated. I assume it's consistent, too. I know for certain it's easy to use. Slide the thumb lever on the SmartHead to select Schrader or presta. Tap the Reset/On button and in a few seconds the gauge beeps and the display updates to let you know you're ready to take a reading. Tap the other pushbutton to toggle through the display options of psi, bar, and kilogram per square centimeter. Once you select a unit of measure the Topeak retains it at subsequent startups until you select another.

While Topeak says the TSG-01 can be used for all Schrader and presta tires and suspension components, it's best suited for Schrader valves on tires. It really hates to let go of presta stems at times. In fact my first TSG-01 came off a presta valve in pieces once. I contacted the distributor, Todson, and they sent a replacement in a matter of days at no charge. Also, the head is kind of fat. It's easy to get between spokes for tire pressure readings but it won't fit tight spaces around shocks or recessed valves on top of fork legs. The short neck further compounds access issues. Why not put a hose on the gauge like suspension pumps have? Because the hose on a pump is pressurized as you adjust the shock or fork. The TSG-01 gauge starts with no pressure (actually, 1 bar of atmospheric pressure) in its neck. Stick it on the valve and air would flow from the area of high pressure (tire, shock, or fork) into the area of low pressure (gauge hose). This would bleed off too much pressure. As it is Topeak says the TSG-01 bleeds 1-1.5 psi each time it's detached from a valve. Another limitation is that while max pressure is listed as 255 psi, the instructions say the “effective tire pressure display zone” stops at 160 psi. I'm not sure what that means. The Topeak Web site has no clarification (it also lists 255 psi max) and no Contact Us option so I can't ask. I do know that for most shocks carrying most recreational riders 160 psi is too low to be useful.

So my short list for improving the TSG-01 would be a bleed valve, an auto reset, and a smaller head/neck. This would provide better access and the ability to over-inflate the item and bleed down to the desired pressure without removing the gauge from the valve. It would still not fit well on most shock valves, but I could accept that limitation. In fact, I can accept the TSG-01's limitations in its current form. Despite those limitations its attributes - ease of use, accuracy, and consistency - make it my first choice when checking pressure.

Photos

The Topeak TSG-01 in its blister pack (above) and in the raw (below).

The TSG has a big, easy-to-read display.

Note in the photo below that the centerlines (white lines) of the gauge and the Schrader valve on my Fox Float RP3 shock can't line up. The gauge is against the linkage and cannot be moved up any farther. Even if it could, the head of the gauge would hit the shock body before the valve core was pushed open.

The TSG won't fit tight spaces on shocks and forks.

The photos below show the effects of parallax. The camera was positioned left, center, and right over the gauge, resulting in readings that varied by about 5 psi.