Yalla!

Head Tube Angle and Reach

Using a 56mm diameter head tube means that if you’re ever in a pinch or want to use your favoured brand of headset, it’s a common diameter that shouldn’t make it hard to source parts.

But a 56mm diameter also gives us room inside the headtube to adjust the reach and head angle of the bike, or both in combination, while keeping everything zero stack.

63° is the base setting, but if you want something more stable up front or conversely, something with a little more sprite in the steering and feel, you can adjust the head angle by 1° each way from 62° to 64°.

Flat-out fast and rough tracks, think legendary Mont Saint Anne, might benefit from the added stability that a slacker head angle brings. Whereas flatter, slower and more picky technical tracks might benefit from the opposite, a slightly steeper head angle.

You can also change the reach of the frame by plus or minus 5 mm. This not only changes the fit of the bike but also changes the load on the front wheel and also the feel of the bike in terms of stability and manoeuvrability.

Lots of the racers we’ve supported are from the UK, and lots of the British National tracks are akin to racing a Star Wars speeder through the trees. Stability is still needed, but a shorter overall bike, in part from the shorter reach, helps to up the agility of the bike and allow it to be chucked around the tightly packed woods with more ease.

Lots of bike park riders might also like a shorter bike, at both ends, to cater to the more man-made nature of the tracks and the manicured radius of a berm or take-off.

Riders and racers looking for that stability needed for tackling a lot of the menacing race tracks will find solace in making the bike longer. It’s not so much adjustability as to make it a new size of frame, but the longer front end gives the bike even more of a sure-footed nature and allows you to focus more on what’s coming up at warp speed, rather than thinking about what the bike is doing beneath you.

The reach adjustment can also help fine-tune the fit. We’ve tried to keep the sizes representative of the size of riders we see on the Yalla!, and also coming from our experience with the Madonna and Jibb. But if you know you’d feel less stretched out or less cramped up, then this adjustability opens the door to make the bike fit that bit better, again leading to a better ride.

We also can adjust reach and head angle together, so if you fancy the sound of longer and slacker, then no worries. Shorter and a bit steeper, not a problem. Our range of headset cups are designed to be a doddle to use with clear and accurate markings on the frame and cups. A good press fit ensures a solid fit and no need to glue cups in the frame to avoid dreaded creaky noises, like some race teams have to do.

BB Height

Our stock BB height is around 345 mm static. With our suspension design, it means we can exploit a low BB height for stability and the ability to turn confidently without compromising the ride height. But we’ve given the option to fine-tune this as well with the ability to go 3 mm higher or lower.

You can raise the BB for more clearance, think janky Snowshoe rock gardens, or drop it for more stability and even more of an in the bike feel, if the terrain isn’t too chunky.

If you prefer to run a soft suspension setup, you can easily raise the BB to account for riding dynamically lower in the travel. Or on the other hand, if you prefer to run a firm setup and want to drop the BB back down a little, you can.

The BB height adjustments will also have a slight change to the leverage ratio, but it’s only very subtle, and each of the three groups of leverage ratio are more defined by the adjustability we have in the suspension progression and leverage ratio.

Suspension Progression & Leverage Ratio

So far the adjustments have been more of a static adjustment. Sure, they will certainly affect the dynamic shape and feel of the bike, but you can measure their change when the bike is just standing there.

The suspension adjustments are more of a dynamic adjuster, really coming into effect when you swing a leg over the bike and send it down the hill.

Our stock setting of 25% progression starts the leverage ratio at 3.08 and ends at 2.31. For us, this setting can work well in all types of tracks and situations, coming back to the idea that if you’re not into tinkering, then no problem. Just pump up the tyres and head out for a ride.

But, it’s possible to adjust the level of progression by plus or minus 3%, adjusting the leverage ratios in the process, especially in the portions of travel that you’ll spend more time in. If your bike is set up well, you’ll usually be spending more of your time riding in the first two-thirds of travel, rather than in that last third, clanging off the bottom-out bumper all day long. If this is the case, then we need to have words.

Adjusting these earlier portions of travel means that the adjustments have more of an effect, more of the time, and can be felt more easily.

The higher, 28%, option will give higher starting leverage ratios, giving you more sag without any adjustment to the shock, or needing more air or spring to maintain the same sag as the mid progression setting.

More progression and higher ratios will make the bike more active in its suspension use while giving more mechanical ramp up as you go through travel. It can work well with shocks that display a more linear character or if you ride in very rough terrain, think Val di Sole rough, or if you are hitting big man made bike parks and like to run your suspension firm.

The lower, 22%, option will lower the starting leverage ratios, giving you less sag without any adjustment to the shock, or needing less air or spring to maintain the same sag as the mid progression setting. It can work well with shocks that are very progressive in their feel or if you ride in terrain that isn’t overly rough and you want to carry speed, think Fort William, or if your terrain isn’t very challenging and you’d like the bike to react more to the inputs you give it.

And in the same flavour as our headsets, it is possible to combine the BB height and progression amount. If you’d like more progression but with a higher BB height, we’ve got the parts for that. Less progression and a lower BB height, we’ve got you covered.

Chain Stay Length

Out back we use the same system to adjust the chainstay length as our Madonna and Jibb, meaning that all parts except the axle are the same between the bikes.

Each Yalla, regardless of frame size, comes with the axle in the middle position, meaning that each rider has the option to go shorter or longer. But we also maintain a balance to the front end length of the bike as the sizes grow by making that middle position longer on each size. M sits at 445 mm, L at 450 mm and XL at 455 mm.

For us, having that balance through all the sizes is more important than trying to get the shortest chainstay length possible on all sizes. We feel that you can ride a bike harder, and have a better ride if the bike is feeling balanced. And even with a 460 mm chainstay on paper, that XL rider’s inputs into the bike aren’t going to be completely sapped up by any mushy suspension, as we considered the two things together during development.

Chainstay length is going to adjust the stability/agility balance while also adjusting the balance in load between the wheels, and altering the suspension a little. But don’t worry too much about that last one, 5 mm longer chainstays only need 2 psi more in the shock to maintain the same sag.

A longer chainstay brings more stability to the bike as well as placing more load on the front wheel, by taking a little off the rear wheel. You’d be surprised just how much change in bike feel up front can be achieved by an adjustment out back.

Shorter chainstays will then bring in a little more agility to the bike, especially in movements like manuals and bunny hops, but we’re also not designing a slopestyle bike, so even a 440 mm chainstay for an M-size rider is still in keeping with our concert of bike that is built for sending it.