Coherny Professional Bicycles Hanger Alignment Gauge Alignment Ranging Tool for MTB and Road Bikes

Excellent product, reasonable price, delivered promptly.

This derailleur hanger alignment tool is machined from aluminum, and it's just as beautiful as it appears in the pictures. Very cool design, and the anodized finish is gorgeous. When I first got it in the mail, I was also surprised by how compact the whole thing is (only 9" long), so it's also a great option if you have limited space. Regardless, it's still a tool with a serious purpose. The various parts of this hanger alignment tool fit together very tightly (but they do fit), including the measuring rod and the red telescoping arm that revolves around the black threaded piece (Most of the black piece is aluminum, but the threads that screw into the hanger are steel). I found that a generous dab of grease helps the measuring rod extend and the red arm rotate more easily. However, initially it was hard to rotate the red arm around the wheel without the tool unscrewing out of the derailleur hanger. I had to repeatedly check to make sure the black part was tightly screwed in, but the red arm did seem to loosen up over time. As far as extending the red arm outwards to various lengths, that was smooth & easy from the get go. The measuring rod came with two black rubber rings to mark positions. My hanger was seriously out of alignment, so I ended up using a crescent wrench to make major adjustments, and then using the alignment tool to measure and verify improvements a few times. Per the instructions, the extending red arm is NOT to be used as a lever; any required bending should be done with the round knob on the black part. As I mentioned, the red arm did rotate around more easily after about 10 minutes, and I finished up by checking the hanger alignment against numerous spots around the wheel. By then, I was actually quite pleased with the tool, and I don't regret the purchase at all, especially considering the price.

I worked in a bike shop for a time and used several other hanger alignment tools. But, none compare to this. It is easy to use, holds it's setting and is very solid and well built. The solid construction allows me trust the measurements. If there is any play in the alignment tool, it gets magnified as you move it from position to position. This tool does not have any issues with play.

This product was cheap and I got a product that doesn't work. Assembly is required and the pieces do not fit. During assembly I broke a piece. I sent pictures back to the seller about my problem and three weeks later I have not received a response. I'm not happy at all with this product.

If you know how to use the tool it will work for a basic alignment but don’t expect pinpoint accuracy. There is play in the connection between the black bar in the red bar when connected which is a bad thing. To get a somewhat accurate reading, you’ll need to pull it back (or push fwd) when taking a measurement. Also, you should NOT use the red bar to bend the hanger into place because it will wallow out the hole in the bar, making it even more inaccurate. Using the black bar only leaves you with little leverage to actually straighten it out but it is doable. For 35 bucks, it will do but I will probably upgrade to the park tool in the future and gift this one to a friend.

Does everything advertised! Perfect fit! Works amazing.From one engineer to another, it might almost be too pretty... I think you could knock some cost out of the machining and still git'r done.Thanks for the great product.

This is beautifully made but unfortunately with the amount of play where the black derailleur hanger bolt goes into the red gauge stick makes it completely unusable. There is close to an 10mm difference on a 700c wheel. I tried making my own collar (15.86mm dia) to stop the play but there was still about 8mm of play. Once they get this solved I would gladly check out again, until then, look elsewhere.

My first one arrived without the M10 stud needed to thread the tool on. Not a huge deal, Amazon sent a new one ASAP. Once I used the tool everything went well. I put a cheater bar on the black piece to do the small bending of the derailleur hanger. The instructions say not to use the red parts to bend.

The derailleur adjuster worked perfectly and was easy to use. Does require a bit of mechanical expertise. Ask for the derailleur straightener video on YouTube and you're on your way!

The shaft wobbles and spins making reliable measuring of the wheel impossible. Buy the solid shaft version, park or superB style.

I also struggled with the wiggling at the main holding bolt which resulted in significant movement at the measuring end of the tool. I was ready to give up on this tool until I realized that the holding bolt is just pressure fit in the main shaft. I pulled it out, added two layers of packing tape, and put it back. Voila! No more wiggling and a good compact tool for the price.

Very poor tolerances , there is a full 1 centimeter of wobble on a 700 rim . A student on their first week of machining could make something tighter than this.

I was still able to fix the hanger misalignment but the tool has too much play. At the full extension i.e. to measure 29inch wheel there was about 6mm play the the top of the tool. One can correct for it but it makes the measurement trickier.