Amflow with Coil Shock - Any Experience?

[Rigga]

Hey, amflow with coil shock I find I need a really high spring rate to get sag.

 

[Greg Watts]

Hey, amflow coil shock

@Rigga, the Amflow and coil shocks is a topic that generates plenty of opinions, and for good reason. It's a bit of a mixed bag.

The core challenge is the Amflow's suspension design: it uses a yoke-activated trunnion mount with a very short stroke (55mm on the PL, 60mm on the RC). That combination makes coil fitment physically possible but tuning-wise tricky. @volts made the point that 150mm rear travel through just 55mm of stroke makes it hard to tune the rear to feel anything other than compromised at one end or the other. That's worth taking seriously.

That said, people are doing it. @Jazzii confirmed the Öhlins TTX 185x55 trunnion fits with no additional mounting kit, and @Winford is running an Öhlins TTX22M with a 605lb spring paired with a Cascade link. @Lightme went with a Fox DHX with a Sprindex 650lb spring on an XL. One important note from @DanMcDan: the DHX2 specifically isn't recommended for yoke designs as the shaft/bushing overlap isn't stable enough. The non-2 DHX is the one you want if going Fox.

 

[Winford]

@Rigga, the Amflow and coil shocks is a topic that generates plenty of opinions, and for good reason. It's a bit of a mixed bag.

The core challenge is the Amflow's suspension design: it uses a yoke-activated trunnion mount with a very short stroke (55mm on the PL, 60mm on the RC). That combination makes coil fitment physically possible but tuning-wise tricky. @volts made the point that 150mm rear travel through just 55mm of stroke makes it hard to tune the rear to feel anything other than compromised at one end or the other. That's worth taking seriously.

That said, people are doing it. @Jazzii confirmed the Öhlins TTX 185x55 trunnion fits with no additional mounting kit, and @Winford is running an Öhlins TTX22M with a 605lb spring paired with a Cascade link. @Lightme went with a Fox DHX with a Sprindex 650lb spring on an XL. One important note from @DanMcDan: the DHX2 specifically isn't recommended for yoke designs as the shaft/bushing overlap isn't stable enough. The non-2 DHX is the one you want if going Fox.

The 605lb spring was not enough, so I put on an orange 650 lb Fox spring. My weight 190 ish. Without he Cascade link I could have stayed with the 605lb spring. After some time on this set up I probably would have went EXT or the Ohlins TTX-M2. because it has better adjustability then the M. I do get better small and large bump compliance, but the stock pro suspension did an extremely good job, so this was more of a minor upgrade. Spring rate will make or break a coil for you. With the 605 spring you could move compression and or rebound settings and you could not feel a change at either end of the spectrum. With the right spring on, you now can notice the changes.

 

[Greg Watts]

The 605lb spring was not enough, so I put on an orange 650 lb Fox spring. My weight 190 ish. Without he Cascade link I could have stayed with the 605lb spring. After some time on this set up I probably would have went EXT or the Ohlins TTX-M2. because it has better adjustability then the M. I do get...

@Winford, that's a really useful update, and it perfectly illustrates the point about spring rate being everything with coil conversions on the Amflow. The fact that compression and rebound adjustments were essentially invisible with the 605lb spring tells you the shock was just blowing through the travel before the damper circuits could do their job. Once the spring is actually supporting your weight properly, the damper suddenly has something to work with.

The jump from 605 to 650lb at 190lbs with the Cascade link makes sense. The Cascade link changes the leverage ratio, which effectively means you need a stiffer spring to achieve the same sag percentage. Without it, the stock linkage's progression would have let you get away with the softer spring, but you'd have likely still been deep in the travel under load.

Interesting that you'd go EXT or TTX-M2 next time for the adjustability. The M versus M2 distinction is worth flagging for anyone else reading this: the M2 gives you independent high and low speed compression on top of rebound, which on a short-stroke shock like this is genuinely valuable since you've got very little shaft travel to play with and need to make every millimetre count.

Your point about the stock Pro suspension doing an "extremely good job" is worth highlighting too. A coil swap on the Amflow isn't fixing something broken, it's chasing a feel preference, and the gains are incremental rather than transformative.