thought it was all good and then it wasn't engaging 3rd gear at all... and 1st gear was such that i would have to hold down the downshift lever during initial coast and a then a few turns of the pedal, and then after a while it would upshift to 2nd all by itself. strange behavior.

took it in to have it looked at and professional help was stumped as well even after an hour of futzing with the cones and locknuts and indicator chain...

later that day i fitted a 30T sprocket i wanted to try out (thinking that the lower ratio would help with steep hills) and yikes the problem was EVEN WORSE... now it was in 1st gear all the time, and with 30 teeth it turned a casual night out to see some local bands into an exhausting amount of pedaling there and then home.

so next day i bought a flat wrench to fit the cones, and was determined to learn how to adjust the cones myself. i took the wheel off, loosened the locknuts to free up the cones on both the drive and non-drive sides, loosened the non-drive cone all the way out and then back in to just finger-tight... did the same for the drive-side and then tightened both just a tiny little bit each until i got to the point where the wheel was moving freely in both directions.

basically, i approached the adjustment as i would my bottom bracket - you want the cones to be snug (so your wheel doesn't wobble, and so the pawls get their necessary tension), but you want the wheel to move freely.

learned three things in the process. 1) if you tighten the cones too much it will greatly effect how tight/loose your chain moves when coasting and backpedaling. 2) depending on your cone adjustment, when you hold the axle in your fingertips and move the wheel in reverse to simulate backpedaling, you will hear the hub click a couple of times per rotation. 3) i now believe that the size of your chainring/sprocket will vastly improve or worsen the hub's ability to shift gears and stay in gear.

i don't know if the clicking while backpedaling in 3rd gear is normal or not but considering that i'm able to get 3rd gear whereas before i wasn't, i believe this behavior is by design... to me it makes sense, because the same "click" is what i see and hear when shifting through the other gears, but in 3rd there's no more chain positions to be 'found' so it clicks and then remains slightly slack as opposed to clicking down to 2nd or 1st...

backpedaling in 2nd or 1st, no click, just while in 3rd.

about #3 - as i said, with a 40T or 30T sprocket i was having all these problems. now with a 48T on my mongoose 20" frame, i was FINALLY able to feel the rush of speed in 3rd gear i had been hoping for all this time... it's almost as if the SRF3 needs to feel a specific amount of 'oomph' being applied to the pedals/chain/cog to get in gear and stay in gear.

p.s. if you want to fit a 48T sprocket on a bmx frame, be prepared to do some hammering... i spent upwards of an hour hammering a 'dimple' into where the chainring was rubbing up against the drive-side dropout arm.