(A) Ensure Bottom Bracket (BB) locator is fastened securely to the “0” end of the ruler. This is design to be a tight fit, and will need knocking on, I usually just tap it on the floor. Ensure that it is fully inserted.
(B) The Bottom Bracket (BB) / Handlebar measuring block needs to be slid onto the ruler next, with the arrow at the top pointing downwards. This line takes into account the 20mm offset when measuring the BB height.
(C) The remaining pieces can then be slid onto the ruler
(D) The Optional Seat Clamp spacer (20mm) can be used if the saddle centre width is wider than 90mm. For wide saddles this spacer helps keep the seat clamp level and square on top of the saddle.
Step 0 – Position the bike
Before you start, ensure that your bike is on a horizontal surface and is stood vertically upright. You can use the angle measurement feature on the app to check this if necessary. Normally standing the bike against a wall is sufficient.
Step 1 – Find your saddle centre
Place the flat face of the seat section clamp on top of the saddle and align with the mid point of the straight part of the saddle rail. Many saddles have measurements marked on the rail, but if yours doesn’t then use a tape measure alongside to find the centre of the straight part of the rail. For the majority of saddles this point is where the width is 70mm (Which is the fully closed position of the saddle clamp), however some designs do vary. If yours is wider, then loosen the allen screw (with a 2 mm allen key) and adjust your tool to the correct width, ensuring that it is a tight fit on the saddle. The intention is that you can then use this to quickly locate the same point on this, and other saddles in the future. Assuming you use saddles of a similar design then you should not need to change this once set.
Once your saddle clamp is set to the correct width, measure the inner length of the gap between the clamp arms and record for future reference, e.g. 70mm. The optional spacer can be added if desired for saddles measuring > 90mm. This will help keep the tool level and square on the saddle.
The App can also be used to check the saddle tilt by placing the phone flat on top of the saddle.
Step 2 – Bottom Bracket position
Dimensions: BB Height
Use the BB/Handlebar block to measure the vertical height from the ground to the BB center (Read from the line with the arrow). Enter this measurement in the app. e.g. 272 mm
Step 3 – Saddle position
Dimensions: BB to Saddle (Top of centre) ‘X’ & ‘Y’.
Enter your desired saddle height (BB to top of saddle at saddle centre) into the app, then place your phone in the phone holder and ensure that it is tight & secure. e.g. 768mm
Place the locator at the end of the tool into the BB centre and position the saddle clamp in the centre of the saddle.
Check the “Measure Saddle Position” switch and the phone will continuously measure the angle of the tool and calculate the saddle X (set back) and Y values in real time. Make adjustments to the saddle position until it is in the correct place.
When the saddle is in the correct position turn off the “Measure” switch to lock the angle. You can still manually modify any of the figures and the others will recalculate as appropriate
Step 4 – Bar position
Dimensions: BB to Handlebar centre ‘X’ & ‘Y’.
Use the BB/Handlebar block to measure the distance from BB centre to the handlebar similar to the way you have just measured the saddle. The dip in the block helps you locate the centre of the bar. You may need to reconfigure the tool and remove the Seat clamp. (You could equally just use the ruler and measure the point at which the ruler touches the handlebar.)
Check the “Measure Handlebar position” switch to measure the angle of the tool and calculate the handlebar X and Y values.
Step 5 – Hand position (Road bikes only)
Dimensions: Hand position height, Hand position to saddle centre distance
Whilst bike fit professionals generally prefer to use the handlebar centre as the main reference point (Step 4 above), for a home mechanic I also find it useful to capture the riders hand position, particularly if you have multiple bikes with different handlebar dimensions, brake lever sizes or a difference in height between handlebar centre and the hand position.
Place a ruler or something similar across the top of the hoods at your usual hand position, then use a tape measure to measure from the slot in the centre of the saddle block to the ruler.
Now use the tool with the Seat block to measure the height from the floor to the hand position. Important: Take the measurement from the TOP of the block not the centre, due to the 20mm offset created at the bottom of the ruler.
Enter this measurement into the app (e.g. 937mm), the app will then calculate the drop from Saddle top to the hand position.
Step 6 – Save a copy of the dimensions
The application doesn’t yet have a save/load feature, but you can use the screenshot feature of your phone to capture a copy of all the settings.
Additional tips and technical details for the App
Application compatibility: The application is a Progressive Web App (PWA), which means it can run on most operating systems in your Web browser and is also installable on your device like a traditional App from an app store. This means it can run when offline, and it can store data locally on the device. The application will run on Android and iOS phones, tablets and laptops. The angle measurement functionality is dependent upon your device having a tilt sensor. The first time you run the app you need to launch it from the web site (Link at the top of this page) There is no charge to use the App.
How to install the App:
Android: Press the install button, or “Install App” from the Chrome menu.
iOS: Click the Safari “share” icon then “Add to Home Screen”
Data privacy: All data used/captured by the application does not leave your device and is not shared with any remote services. Usage metrics are also not captured/tracked.
Device sensors: The application uses your devices tilt sensor, iOS devices will request access for this capability the first time you run the App. It is important to ensure that you grant access to this capability when prompted. If you accidently ‘denied’ access then you need to clear your devices browser cache then load the app again.
How to launch the app: Once the app is installed a launch Icon will be added to your device similar to any other app from your devices App Store and the app can then be launched directly.
How to get updates: The application will be updated over time and you will receive updates automatically. Normally it takes 2 reloads of the app for it to pick up changes from the server.
Current Application version: The current application version is 3.1. You will normally have to reload your application twice for it to identify and apply the update. If you are not seeing the correct version follow the instructions below, the same as for “other issues”.
Other Issues: If you have any issues with the application try the following steps:
1. Restart the browser
2. Reset/empty the browser cache
3. Uninstall the application and run again/install from the website.
If the issues still persist then please email firstname.lastname@example.org.