We test the new Rotor INspider MTB compatible with Shimano cranks

ROTOR recently expanded its range of power meters with the addition of the new ROTOR Inspider® MTB Shimano® Compatible, which allows you to enjoy its spider power meter on your Shimano cranks. Since its recent launch on December 20, we have been able to test it and below we bring you all its details.

News and features of the Rotor INspider MTB Shimano Compatible

This new compatibility of the second generation of the Rotor Inspider® is specific for MTB and allows to mount the power meter on the Shimano XTR, XT and SLX cranks. It is manufactured by CNC machining with 7075-T6 aeronautical aluminum. It has a more reduced and compact design than the first generation, thus being more integrated into our bottom bracket. Now it is compatible with any current MTB frame that equips Shimano cranks.

This smaller size and the reduction of the BCD to 100 mm allow it to mount chainrings from 30 teeth, including oval Q-RINGS chainrings, thus expanding the possibilities of developments for all users. For this, a characteristic shape has also been given to the chainring bolt housings, which decrease their section as they move away towards the outside, in order to allow the circulation of the chain avoiding any friction with the spider. The bolts screw directly to the chainring and are made of steel instead of aluminum.

At the expense of this feature is the lower availability in the market of chainrings with this BCD. It is a new standard created by ROTOR that will surely extend to other component manufacturers to make their chainrings compatible with the INspider meter.

Low weight and accurate measurements

Its weight is only 99 grams (almost 50 grams less than the first version of the INspider), without chainring, checked on our scale. A figure that places it as a reference among the lightest spider meters on the market. With a 34-tooth chainring, which is what we have used and what is probably the most widespread among users, the weight stops at 169 grams. The weight increase that is added to the bicycle is insignificant compared to the benefits of training with a power meter.

As for the measurements, it offers an accuracy that stands out for its margin of error of +/- 1.5%. Rotor ensures that it is capable of giving accurate data even with its oval chainrings, thanks to the multiple measurements it makes in each revolution. By estimation it gives the power values of each leg. As expected in ROTOR, its meter has its own OCA and OCP metrics, which allow us to know the most favorable angle of pedaling and with it the most optimal position in which to place the oval chainring. Although in this case, the OCP technology cannot be applied to Shimano cranks, since their spline only has one position. To be able to make use of it we should acquire Rotor cranks together with the INspider meter.

IP67 protection and a renewed App

Regarding its durability and resistance, it stands out for obtaining an IP67 certification that ensures the protection of its electronics maintaining the tightness against water, dust or mud, standing above its competitors in this aspect. In addition, Rotor ensures accurate values in a temperature range between -20ºC and 50ºC thanks to its compensation system. Its smaller size also allows it to reduce the possibilities of bumps and impacts.

It can be connected via Bluetooth and ANT+ to cycle computers and any Android or IOS mobile through its ROTOR Power App. In it, in addition to updating its firmware, you can record your activities, adding or configuring the necessary screens. You can get the OCA and OCP values through the Torque 360 graph that we can use to improve pedaling performance. It even allows you to share the activities performed with Strava and TrainingPeaks.

Great autonomy

The battery autonomy has been improved compared to the first version, becoming 350 hours of use (200 hours in the previous model), that's many MTB outings without needing to charge the device. To charge its Li-ion battery it uses a proprietary design charger, with magnetic connection directly to the power meter. Effective and easy to use. 

We test the ROTOR INspider MTB Shimano Compatible

Our test of the ROTOR INspider MTB Shimano Compatible began with its assembly. Starting with the placement of the chainring, in its round version for a first test. A simple assembly on the crank that is done as if we were changing the chainring for another one. We remove the original chainring from our Shimano XTR, place the Rotor INspider power meter in its place and it is ready to be used.

To link it, you just have to turn the pedals a little and the cycle computer or the mobile App quickly detects it.

Prior to our first outing we calibrated the meter. An equally simple process, which we can perform from the App or directly from the cycle computer, leaving the pedals free and placing the cranks in the correct position.

During our outings with the ROTOR INspider® we have not noticed communication losses or strange power peaks. It has offered stable and coherent data at all times, which have remained similar on the days that the test has lasted. Only in the measurement of the balance of pedaling between both legs is where we have noticed a little difference compared to our pedals with power meter, showing a more adjusted balance than that of our usual meter.

Although the crank lacks the possibility of adjusting the Q-RINGS chainring, the Torque 360 graph included in the App provides us with useful data to help us improve our pedaling efficiency. 

During all the outings we have made, we have not had any connection failure between the cycle computer and the meter, even combining both with the mobile App we have had continuous reading on both devices without cuts.

The connection to charge it is very handy and is perfectly fixed magnetically. During our outings the power meter has been exposed to mud and water with some pressure during the cleaning of the bicycle, without showing signs that the weather conditions can affect it. Even so, we do not know how it will be affected over time, as it lacks protection against possible impacts.

There have been several days of testing in which we have not noticed noises caused by small clearances, possibly thanks to the fact that the device is anchored and fitted in the same way as the original Shimano chainring.

Conclusion

The ROTOR INspider MTB Shimano Compatible can be a very interesting option for users who want a power meter while keeping their Shimano cranks. For an adjusted price of 449€, a figure below many of its rivals, and adding only 99 grams of weight, we get a good performance and a reliable data report for training and competitions.

Specifications

Plates available	30T  |  32T  |  34T  |  36T oval and round
Weight (with R34 BCD100x4 crankset)	160.5g
Material	7075-T6 aluminum CNC - Black anodized
BCD	100x4
Measurement	Both legs (Right-Left combined)
Data	Power  |  Cadence  |  Balance (estimated)  |  Torque 360  |  OCA (Optimum Chainring Angle)
Data accuracy	+/- 1.5%
Battery life	350 hours (Riding Time)
Battery type	Rechargable Li-ion + USB cable
Connectivity	ANT+™ & Bluetooth® Smart compatible
Wireless technology	ANT+™ 2.4 Ghz | Bluetooth® Smart
Water resistance	IP67
Frame compatibility	Compatible with all MTB frames
Groupset compatibility	Shimano® 1x12 |  SRAM® 1x12 Eagle ®

For further information and to purchase, please visit the official Rotor website.