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How to adjust chainline for 2×10 crank set

6 min read

Asked by: Kathy Lopez

How do you adjust a chainline?

Chainline may be adjusted at the rear wheel by rearranging spacers on the rear axle, and with a steel frame, also by re-spacing the rear dropouts. Adjustable hubs use conventional threaded axles, so you can increase the OLD spacing by removing the locknuts and adding spacer washers, and replace the axle as needed.

What should my chainline be?

1. What is a bicycle chainline? Middle of the front chainring and middle of the rear sprocket should be at the same distance from the axis that goes along the middle of the bicycle frame from the front to the back. That means the chain will run completely straight from the front to the rear.

How do I know my chainline?

Chainline is the distance between the centerline of your frame and the average centerline of your chainring(s). For 1X this is easy – If the center of your chainring teeth is 49mm from the centerline of your frame then your chainline is 49mm.

Why is chainline important?

The chainline is very important for several reasons: more efficient transmission; the less you bend the chain, the smaller the power loss; better function and less chance of the chain falling off the rings; less wear due to less friction; better function of the front derailleur; and quieter operation.

How do you put chain lines on single speed?

Quote from video: To my chainring to the center of my chain ring and we're at let's say 50 51. And 1/2 let's say 52 millimeters. So that is my other number 52 millimeter – let's say to chain.

What chainline is super boost?

Super Boost Plus 157 uses the exis ng chain-line developed for DH bikes but uses standard trailbike BB widths and crank combinaYons to take 29” and Plus bike performance to the next level.

Which is better 1X or 3X crankset?

Gear range of different drivetrains:



In the above example of bikes with common drivetrains, the 1X bikes top out at 47 to 48KPH in their highest gear, while a 2X or 3X bike will offer 15-20% more speed, topping out at 56 to 57KPH.

What is chain ring offset?

The offset of a ring is how much it is dished over from a standard flat chainring, it is used to achieve correct tyre/frame clearance and also to set the correct chainline.

What is boost spacing?

Boost spacing allows for wider hub flange spacing, which correlates to better spoke bracing angle and dish when building wheels (this makes the wheels stronger). The brake rotor sits 3mm outboard of where it did before, as does the rear cassette.

What does boost crankset mean?

boost just refers to bikes that have a 148mm wide spacing between the dropouts for the rear hub, the Drivetrains are shifted outboard by 3mm. This may or may not affect the crank axle length depending on the bike and crank combo, In most case it has just resulted in wider q-factor cranks and not longer axles.

What is the difference between boost and non boost crankset?

The only different between boost and non boost drivetrain kits is the crankset. The only different between a boost and non boost crankset is the chainring. You can swap a crankset from boost to non boost or vice versa just by installing a different chainring. Hope this is helpful!

What is the Q-factor on a bike?

Q-factor is the distance between the outside face of each crank arm at the point where the pedal attaches, while stance width is the distance between the centre of one pedal to the centre of the other.

How important is chainline on a single speed?

Chainline is important on all bicycle drivetrains but especially so on a one-speed. A perfect chainline is one in which the chainring and rear cog are in perfect alignment with each other and the chain takes a perfectly straight path from the chainring to the cog.

What is the best single speed gear ratio?

around 2.7-2.8

If you’re just starting out on your adventure on a single speed or fixed gear bike, a gear ratio of around 2.7-2.8 will be ideal.

How many teeth does a single speed have?

A gear ratio is determined by the number of teeth you have in the chain ring and the rear cog. We personally recommend riding a fixed gear or single speed bike with either 44 or 46 teeth in the chain ring (hence the first number in the gear ratio) and a rear cog with 16 teeth.

What is chain ring offset?

The offset of a ring is how much it is dished over from a standard flat chainring, it is used to achieve correct tyre/frame clearance and also to set the correct chainline.

How many spacers does a 73mm bottom bracket have?

For 73mm Shimano HTII bottom brackets



If your bottom bracket shell is 73mm wide, you only need one 2.5mm spacer fitted to the drive side.

What is the difference between boost and non boost crankset?

The only different between boost and non boost drivetrain kits is the crankset. The only different between a boost and non boost crankset is the chainring. You can swap a crankset from boost to non boost or vice versa just by installing a different chainring. Hope this is helpful!

What are bottom bracket spacers for?

Bottom bracket spacers are used to adjust the spindle position to add extra clearance, or to fine tune chainline. For example, if your inner chainring is too close to the chainstay you can add spacers to move the crank outward just a bit. They are really great if you want a perfect chainline on a fixed gear bike.

Do I need spacers on my crankset?

For all cranksets with a constant diameter spindle (30mm, 29mm DUB and 24mm), spindle spacers are used as needed to remove any side-to-side play of the crank, and to center the crank in the frame. For most installations, the included spacers will be enough to properly position the cranks in the BB.

Where do the spacers go on a bottom bracket?

Quote from video: Side with your left-hand side crank arm attached to it goes through. And then pokes out the right-hand side and then your chain ring on this side with your arm. Goes on to the axle this side on these