Slip-assist makes things comfortable
Ped discovers that the Triumph’s clever clutch makes riding a breeze
As I mentioned in my last report, Triumph’s Street Twin is a fool-proof way into retro bike ownership. Not only is the Street Twin amazingly easy to ride with its low seat height, friendly power delivery and lightweight controls, but behind the classic facade, it also boasts some hidden, hi-tech help such as traction control and a slip-assist clutch.
Slip-assist clutches aren’t that new but the way they work is interesting. Inside a slip-assist clutch are the usual things you see in a normal clutch such as springs, a pressure plate, clutch plates and a clutch basket, and the way a slip-assist clutch is engaged or released is the same too. When a clutch is engaged (lever away from the bar) several springs press the clutch plates together creating enough friction to enable drive to the gearbox. To disengage the clutch (pulling the lever to the bar) a rod presses onto the rear of the pressure plate, compressing the clutch springs and freeing the
plates, allowing them to slip and disengaging the clutch.
The extra components in a slip assist clutch are a series of sliding ramps on both engine and gearbox sides of the clutch. When the clutch is fully engaged (lever fully out) and the torque between engine and gearbox increases (as you accelerate) these ramps slide up onto each other gradually increasing the clamping pressure between the clutch plates. When the torque between engine and gearbox is reduced (as you decelerate) the ramps slide back to their original positions. In a slip-assist clutch the springs are no longer required to provide all the pressure to drive the clutch plates (as they are in a normal clutch) so the springs can be weaker, resulting in less effort needed to pull the clutch lever.
If you’ve ever ridden a bike with a heavy clutch you’ll know how tiring it can be. For an inexperienced rider, anything that disturbs or interrupts the concentration is bad news. I’d argue that for a new rider the slipassist clutch is more important than something like traction control (in my experience novice riders are usually extra cautious when accelerating on slippery or broken surfaces anyway). For the experienced rider it just makes the Street Twin a nicer, relaxing place to be. On a winter city commute every
‘The slip-assist clutch is more important than something like traction control’
TRIUMPH STREET TWIN £7350 FUEL 12ltr@63mpg = 164 miles WEIGHT 198kg (dry) SEAT HEIGHT 750mm POWER 54bhp TORQUE 59ftlb PED BAKER Enjoys tinkering nearly as much as he does riding the Triumph. HEIGHT 6ft 4in WEIGHT 90kg
Stop making me look an ass Less clutch lever effort makes for a more relaxed ride
Bottom looks a right Titania on the Street Twin on his way to apologise to Puck