Is Long, Low and Slack Geometry Right For You?

Starling Cycles started making bikes when the “long, low, slack” geometry movement was in its infancy. 

With early prototypes, we experimented with a range of geometry configurations. We tried super low BBs, super slack head angles, long and short reach, slack and steep seat angles, long and short chainstays… And more.

We found that a longer and slacker bike with a reasonably low BB and longer stays worked well, albeit within reason. 

If you’re a strong, powerful rider capable of manhandling the bike around in rough terrain, or regularly ride very fast tracks, you might benefit from a slightly longer and slacker bike.  Similarly, if you only ride super tight tracks, there’s a slight benefit from a steeper bike… but not much!  

We also found a strong relationship between front-centre and chainstay length. The longer front-centre compliments the longer stays. But it’s not quite that simple, longer stays do make the bike more stable, but also harder to manual and generate pop.  So longer stays are better for a rider who takes the direct line and carves corners, the shorter stays for those who pop off every root and lip and like to smash corners.

There’s also the effect of wheel size and weight, and there’s a whole article on that elsewhere here in the Starling Tech Journal. Similar to chainstay length, bigger and heavier wheels are suited to bigger bikes and more stability.  Smaller, lighter wheels are more suited to pop and manoeuvrability. 

There’s also one other aspect to smaller wheels, that for smaller riders the smaller wheel helps reduce the chance of the rear wheel hitting your bum on steep drops.

The geometry used on Starling bikes is good for pretty much everyone… except for those who aren’t honest with themselves and their capability. 

The range of wheel sizes on different models and chainstay length means most people can find the right bike. It should be noted that a small size bike is not available with the longer stays and bigger wheels of the Murmur. The balance of reach to chainstay length is not correct. Similarly, there’s no XL option with the smaller wheeled Swoop, it just doesn’t work as well.

It’s quite interesting to see that nearly all of the major brands are now zeroing in on sizing that Starling Cycles first used 3-4 years ago.  

Joe Mcewan

Ex-aerospace engineer Joe Mcewan is the founder and chief engineer of Starling Cycles. Passionate, outspoken and fond of a cuppa and a debate, Joe loves to challenge the established thinking of the industry.