For 2016, Scott has gone big on the new 27.5in Plus wheel size, launching eleven models in total from hardtails to ebikes to run alongside its current range of 27.5in and 29in models.

So what’s the Plus tyre size all about?

It’s basically fatter tyres and wider rims. Think of it as the acceptable face of fat biking with tyre sizes in the region of 2.8in to 3.0in. The wider rims make the fatter tyres more stable so they are much less likely to roll off or burp when running lower pressures.

The fatter tyres produce a much bigger contact patch, which dramatically increases traction. They also increase the wheel radius so they roll over bumps better and the extra height of the tyres offer more suspension too.

>>> For more info on how the wheel sizes measure up click here

Exactly how much bigger is the contact patch on a 27.5in Plus tyre?

According to Scott, a 2.8in Plus size Schwalbe Nobby Nic at 1.0bar has a 21 per cent bigger contact patch than a 2.35in Nobby Nic at 1.7bar. Additionally, pinch flat resistance is increased by 8 per cent with the fatter tyres.

 

Sounds great. Are there any drawbacks?

Yes, the main one is that the wheels are heavier; typically 250g more than a regular 27.5in wheelset with 2.35in tyres. Tyre choice is also limited at present.

Rolling resistance isn’t a big issue as you’d think — the difference is as little as 1 per cent. And while you definitely notice the extra weight of the wheels when leaning in or accelerating out of a turn, the fatter tyres don’t feel draggy when pedaling along at a constant speed.

So can I plug 27.5in Plus wheels into my Scott Genius 29er?

Nope, that would be too simple! The issue isn’t the rim diameter — the difference in wheel size between a regular 29er wheel and 27.5in Plus is as little as 10mm. And this is why Scott has been able to use the current Genius 900 front end on the new Genius 700 Plus bikes.

The problem is the width; frames and forks need to be wider to gain the necessary clearance for the bigger tyres. Dropout spacing has also been pumped up to the new Boost standard to make the wheels stronger.

So the Plus size Scale, Genius, Genius LT and Genius E-bike all see the rear axle standard increase from 142x12mm to 148x12mm and the fork dropouts grow from 100x15mm to 110x15mm. You can read more about the benefits of the Boost standard here.

 

>>> Click here for our review of the 2015 Genius LT 710

How do I know which wheel size each model has?

Is not as complicated as it first sounds. All of Scott’s 900 series bikes have 29in rims while 700 series bikes get 27.5in rims. So the Genius 700 Tuned Plus has 27.5in rims and Plus size tyres.

 

Do the Genius bikes still have adjustable geometry?

Yep. A flip chip in the upper shock link lets you choose between a high or low setting. The Genius LT no longer comes with offset headset cups though.

 

So Scott had just changed the wheel sizes and widened the frames to take the bigger wheels?

Hardly. One of the key changes for 2016 is that the TwinLoc suspension has been improved. You still have three distinct modes, Lockout, Traction Control and Descend but the addition of new EVOL negative air sleeve on the Fox shock brings improved small bump sensitivity in Descend mode.

At the other extreme, the Lockout now offers a very firm platform. The TwinLock lever has been improved too and is mounted under the bar in place of a L-hand shifter on all models with 1×11 drivetrains.

The wheel size changes have knock-on effects for the bikes’ travel, too. The Genius LT 700 Plus has 160mm travel front and rear instead of 170mm like the standard 27.5in bike. Because the Genius 700 Plus shares a front end with the Genius 900 it also has 130mm, but it does get 10mm extra up front to compensate for the difference between 29in and 27.5in Plus wheels.

Is the new Scale 710 Plus hardtail a race bike?

No. The focus here is trail riding. The bespoke Plus size frame gets slacker geometry for improved handling on descents and the stem lengthens have been reeled in too. In many ways it’s more like a Genius 700 Plus hardtail rather than a member of the Scale family. All that’s missing is a dropper post!

>>> Scott Scale 770 review

Did you mention a Genius E-bike?

We sure did. Last year Scott introduced the E-Spark and this time round it’s the more capable E-Genius 700 Plus that gets a Bosh Performance CX 250w motor. All three bikes in the range get 140mm forks married to 130mm travel on the rear. The top-end E-Genius 710 Plus featured here comes with the wide range 11-speed Shimano XT cassette, a very welcome addition for attacking the steepest climbs.

When will the Plus sized bikes be available?

Pricing and delivery are still to be confirmed but stay tuned for first rides in an upcoming issue.

For more info visit the Scott website here