157 (Super Boost) uses a 0mm offset chainring. For a 135mm rear hub, you'd use a 6mm chainring.
What offset for non boost chainring?
There are 3 offsets: Standard Road/CX/Gravel: 6mm offset for cyclocross and road crank applications with 47mm chainline. Standard MTB: 6mm offset for non-Boost mountain bikes, GXP and long spindle BB30 cranks for 49mm chainline. Boost: 3mm offset for 52mm chainline.
Can I use 6mm offset with Boost?
From this article it looks like the ideal chain line for boost is actually achievable with a 6mm offset rather than 3mm, with the caveat being that if you want to run a 32t or 34t chainring you're not going to have enough frame clearance.
What is the difference between a 3mm and 6mm offset chainring?
3mm is boost, 6mm is non boost. I have a boost frame, but am running non boost wheels, but with a non-boost chainring to keep the chainline sensible.
What is my chainring 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.
20 related questions foundWhat is boost offset?
To guarantee the same drivetrain performance, Boost compatible cranks are absolutely necessary, or directly mount the Boost-specific chainring Spider. This offsets the drivetrain by 3mm to equalize the cassette's movement. The cranks' Q factor remains unaffected, as too do the axle and bearings.
What is boost on chainring?
For those not familiar with what "Boost" is, it really just refers to a widening of the axles on mountain bikes. From 100mm to 110mm in the front and 142mm to 148mm in the back.
Should I get an oval chainring?
As a direct consequence, Oval rings enhance a cyclist's ability to spin with a smoother power delivery and feel much easier on legs while climbing. Meaning you will go faster and get less tired. You will actually feel your pedal stroke to be more "round" with an Oval chainring than with a round chainring.
Can I use a non boost crankset on a boost frame?
The boost version has 3mm of offset. I was under the impression (probably incorrectly, but it hasn't affected my application) that there is no boost or non-boost specific crankset and that chainring offset is the determinant. Regardless, the short answer is yes.
Is 52mm chainline boost?
Shimano states 52mm to be boost and 142 dedicated, 55mm apparently boost dedicated giving better chain line. Looks like there isn't a 55mm “better” boost for XTR. I found 55mm to be much better for boost with a 5010 frame.
What should my chainline be?
The bike center line is an imaginary plane running front to rear through the middle of the bike. For example, a front crankset and/or front derailleur might be designed to have a chainline of 47.5mm. This means it will work best when the middle of the crankset is 47.5mm from the middle to the bike center line.
What is MTB chainline?
Chainline is measured as a distance from the center of the frame to the center point of a cog tooth. Most 9, 10 and now 11 speed MTB drivetrains and frames are based around 49-51mm front chainlines as specified by component manufacturers.
What is MTB crank offset?
Offset moves the chainring further away from the crank and closer to the seat tube. Reducing the offset from 6mm to 3mm on a long-spindle (external bearing BB cup) crankset will result in a 52mm chainline.
How is SRAM chainring offset calculated?
If you existing chainring is a direct mount SRAM ring the offset is usually stamped on the inside of the ring.
What is the difference between 30t and 32T chainring?
On a mountain bike, the small change of swapping from a 32t to a 30t chainring gives you gearing that is 6.7% easier. For gravel, going from a 42t to a 40t provides 5% easier gearing. That could be the difference between conquering a steep climb and being forced to get off and walk.
How does chainring size affect speed?
The number of teeth in the chainring determines the output you create in moving the bike forward while you pedal. For example, a 28t chainring will feel lighter and have less resistance when pedalling while a 36t chainring will feel harder to pedal against and have a strong resistance when pedalling.
Can I change chainring size?
Yes, you can. This will make it suitable for diverse terrains and make pedaling easier. Putting a smaller chainring on your road bike isn't a problem but you may have to change your crankset. Most road bikes come with double chainrings and can either be standard or a compact.
What is Super Boost Plus?
What is Super Boost Plus? Super Boost Plus (or SB+ for short), is a “standard” of rear axle spacing for trail and enduro bikes. Introduced by Pivot Cycles in 2016, SB+ builds on the increased rear wheel and frame strength brought about by the change to Boost 148 mm spacing.
What is boost wheel 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.
Are boost cranks different?
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.
How do I convert non boost to boost?
You can just order a boost-conversion kit off of ebay with two 3mm spacers on each side, 3mm brake rotor spacer, and re-adjust your derailleur. That's how I run my non-boost rear wheel in a boost bike and it works beautifully. Compatible with 142x12 Rear Industry Nine Torch hubs. They say a re-dish is needed.
What is the difference between boost and non boost?
Boost is ever so slightly better for stiffness but 6mm is pretty minimal, mostly unnoticeable for an average rider. New rims, especially going wider makes far more difference than boost ever will. Boost however is 3mm more room for the cassette, makes a big difference when going wider tires.
