ZTTO Derailleur hanger alignment tool in cool anodized colours! The DAG5

The ZTTO HAG5 is a $30 derailleur hanger alignment tool, made by a ZTTO a Chinese Bicycle manufacturing brand specialising in metal tools and bicycle components. They mainly manufacture from aluminium and often in many anodized colours.

I purchased my tool on e bay from a seller called Not Your Mums garage! they have a lot of ZTTO gear. You can also buy from Alli Express and a few other select places. There seems to be some copies of the ZTTO tool on Amazon, but be careful what you buy, things that appear the same often aren’t in real life and the engineering details matter on bicycle products.

weird shifting bro!

You are experiencing strange shifting, because your bike fell over and hit the derailleur or you crashed your bike – nowyour gears are a bit wonky or maybe very wonky!
The ZTTO HAG5 Its a tool to fix this issue, it checks, straightens and aligns your derailleur hanger. A quick trip to the bike shop can fix this, or you can buy a tool and easily learn to fix yourself.

There are a few manufacturers on the market that sell these types of repair tools, like Park DAG 2.2 $85, Abbey Bike hanger Tool $205 and a whopper Park DAG 3 $130. When comparing to other manufacturers you will notice the ZTTO is almost 100% aluminium, apart from the screw threads. Other brands tend to be steel, plastic and alumnium. Not that this material matters too much as long as the product performs well, which we will get to.

The ZTTO design is simple yet well thought out, it uses machined parts and simple shapes to offer high functionality. It comes in a variety of annodized colours, Blue, Gold, Purple, Silver and of course Black. Maybe you are itching to match your tools with your Chris King or Paul Components products :-)

The ZTTO tool is a checking tool, but it’s also used to bend and correct a hanger back to shape (alignment) , so it needs to be mechanically strong and well designed to apply a straightening force. ZTTO use tubular shapes, which are inherently strong, they have also considered leverage to make the job easier, which is why this tool is 15″ long.

The basic rundown.

The main principle is that the shifter works the best when its properly aligned to the wheel and cogs.
The plane of the derailleur hanger should be parallel with the plane of your wheel for perfect shifts. This is since the axle is sat at 90 degrees to the wheel plane and the cogs are aligned to that axle.
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After removing the derailleur mechanism, The head screws into the derailleur hanger hole. The arm rotates in a circle and the horizontal gauge / rule, measures the offset (or runout) at various angles or points on a circle.
If the offset is the same all the way around, this indicates the planes are parallel and great. If the offset is for example more at 90 degrees position around the wheel, this indicates the hanger is bent inward in that direction.

How to use the Derailleur Alignment Gauge

1. Put your bike in a stand, or upside down might work in a pinch. You will need the ability to rotate the rear wheel.
2. Ensure your rear wheel is mounted correctly and firmly attached. This is very important.
3. Shift into the smallest cog before doing this, and the smallest chainring up front. The remove the deraillur by its main bolt where it attaches to the hanger.
4. Screw in the ZTTO tool to the derailleur hanger.Becarefull not to strip the treads and use a little grease.
5. Place the wheel valve stem in the 9 o clock position, use the tool gauge and extend the gauge to the rim. Note the reading.
6. Rotate the wheel and valve stem to the 3 o clock position, use the gauge to make a reading.
7. Compare the readings, if all are identical then the hanger is straight.
   If there is a discrepancy, then the hanger is bent in that plane. Compare 9 and 3,
   Use the handle on the tool to gently bend the hanger until the readings are similar.
   Apply small amounts of slow force to coax the metal to bend.
8. Rotate the wheel and valve stem to the 12 o clock position, use the gauge to make a reading.
9. Rotate the wheel and valve stem to the 6 o clock position, use the gauge to make a reading.
10. Compare the readings, if all are identical then the hanger is straight.
    If there is a discrepancy, then the hanger is bent in that plane. Compare 12 and 6
    Use the handle on the tool to gently bend the hanger until the readings are similar.
    Apply small amounts of slow force to coax the metal to bend.
11. When the hannger is straight, uncrew the tool and remount the derailleur.

Advantages of the ZTTO tool

The HAG5 is well made and pretty well designed. The design or engineering. when set up correctly and carefully used (see rest of review) it is precise.
The tool stores well when not in use, the attachment shaft, retaining screw and gauge slide into the tube and store away nicely. This makes for a good consumer level tool that’s maybe kept in a drawer or tool bag where you don’t want to loose parts and space is a premium.

ZTTO Tool In Use

Drawbacks of the ZTTO tool

At first glances this $30 tool seems dreamy, but there are some smallish drawbacks.

1. The tool doesn’t come with instructions, like the operating procedure I listed above. Not a big deal but it would have been nice and omitted some research.
2. The Calibration Gauge (photo 3) is a very difficult to read because of low contrast markings and doesn’t have a quick way to mark. Some other tools come with rubber O rings on the gauge so you can slide, mark and reset position easily. If you are handy you can find some small grommets at the hardware shop to slide on the ZTTO gauge. We used a sliding red zip tie to mark it worked pretty well.
3. When measuring alignment at 3 and 9’oclock you swing the main arm from 9 to 3 position, passing the frame’s seat stay which means you have to retract and move the Calibration Gauge. You can see in picture 2 (above), as soon as you loosen the screw, the Collar can rotate on the tube. Providing some inaccuracy if not super careful.

Issues #2 and #3 means you have to be very careful to be super precise. We have a few workarounds like using a zip tie or finding some grommets. As far as controlling collar rotation, you could mark a lengthwise line on the tube and a small marker on the end of the collar. (see photo) This would allow you to move the collar and keep some constant alignment by aligning the marks. the anodised finish of the tool would mean marking the tool by scoring /scrathcingwould be very easy. Just removing some blue colour.

How would we improve the tool

We would machine a small slot in the length of the tube, this would allow you to lock / control the rotation of the collar as it slides down the tool. The screw on the collar can be used to run in the channel.
Make better contrast markings on the Calibration Gauge or provide some small rubberO-rings

Why is this tool inexpensive?

An obvious question given many other tools are $70+. The ZTTO tool is pretty clever in design. It’s made from very simple and mass produceable procedures. There is no welding, all the parts are user assembled, so there is no assembly cost at the factory and they use simple naturally strong shapes that can be machined and modified easily – Tubes.

Takeaways

The ZTTO HAG5 is a prosumer tool, meaning a high end consumer grade tool, that wouldn’t necessarily be out of place in a bike shop (maybe with a few modifications).
It’s easy to use, well built, precise and an attractive price. There are a few small downsides, with some craftiness you can get around them and the tool provides a high degree of accuracy. So you can spend $30 with some quirks or $90 on a park tool, with a few less quirks. If you intend to use this tool once or twice, I think the $30 offers high value for the features provided. If you intend to use the tool carefully this tool is excellent value.

Something to consider, manufacture of this tool is in China, where different / lesser environmental regulations apply. Anodizing can be a very toxic process and can easily pollute sources of drinking water, contaminating with harsh chemicals.

About $30 on ebay – the seller Not Your Mums Garage, is very fast and trustworthy.

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