Park Tool DAG-2.2 Derailleur Alignment Gauge: Rider Review

 Our "Rider Review" article series features the honest reviews from verified purchasers of Worldwide Cyclery. They contain the photos, thoughts, feedback & overall review you are looking for. 

As a mountain biker, there are a few things you should learn to fix at your house, one of those is shifting. Sometimes its just cable tension, but other times you whack your rear derailleur and throw the derailleur hanger out of alignment, to fix that you need a Derailleur Alignment Guage or Tool. Park Tool is the most prominent bicycle-specific tool manufacture in the industry, making so many component-specific tools, including this Park Tool DAG-2.2 tool we are looking at today. Such a simple tool, that makes a very simple alignment adjustment, can make all the difference while out on the trail riding and shifting through your gears. Let's see what Mark has to say about his journey to purchase and use the DAG-2.2. 

Mark's Review of the Park Tool DAG-2.2:

This tool is a must for any home mechanic. Before purchasing this tool I thought that I could get by without it. I saw the $80 price tag and figured I could buy a lot of new derailleur hangers with that money. I was mistaken. Derailleur hanger alignment was the reason I could not get a perfect clean shift every time and that all ended as soon as I bit the bullet and picked up this tool. I looked into cheaper options before picking up the higher end Park Tool model and am glad I did. As someone has said, “Only a rich man can afford cheap tools.” Do yourself a favor and spend the money now to get a tool that will withstand the apocalypse. Seriously this thing is beefy and never going to fail you.

Being a fan of riding skinnies basically requires me to own this tool. I can’t tell you how many times my back tire slides off a skinny and has wrecked my hanger. My old technique of using an adjustable crescent wrench to bend the hanger what I thought was straight. This worked but was not nearly as precise. This thing gets my hanger back to brand new and the days of spending hours messing with the tension of my derailleur cable are gone.

The Tool In Use:

Using the tool is simple. You take your derailleur off, screw the DAG-2.2 into your hanger and then use it as a lever to bend the derailleur back to straight. To properly align you adjust the metal bar on top and match it up with the rim where the valve is. You then rotate the wheel so that the valve is in another location and recalibrate. Do not move the bar that goes to the rim but you can slide the rest of the tool up and down to match the rim. Align the bar with valve again and if it does not align then you know your hanger is off. To fix, just bend the hanger in the direction that you need and recheck the alignment. Once the calibration bar on top meets the rim when turning the wheel in 360 degrees you can be certain it is straight. My biggest tips to make this a smooth process are first, be careful when screwing the tool into the hanger. Hangers can be notorious for being stripped easily so make sure that it is aligned properly before installing. Next, make sure you are measuring the rim in the same spot. Your rim may be out of true so if you use a different location to check alignment you will not get an accurate alignment. (I use the valve for reference). Lastly, know when it’s time to replace a hanger. I do believe that each time you straighten the hanger it loses a bit of integrity. I find that hangers will bend easier and easier until it is worth purchasing a new one altogether.

Final Thoughts:

Overall, the Park Tool DAG-2.2 is a great tool that I highly recommend to any home mechanic. The simple, yet, highly effective alignment gauge has saved me lots of time and frustration getting the shifting correct after a crash or hit to the rear derailleur. It does the job right and will last forever which is everything you can ask for from a tool.