This review is for the Fly Proton Freecoaster and the Cassette version. Everything is the same on these two bikes except the driver, which you will choose when completing the checkout process. Fly designed the 2020 Proton to be a well-rounded street machine, with a 13″ chainstay, 4 pc bars and a freecoaster option. It even comes with 4 pegs and hub guards.
✅ – Full Chromoly
⛔️ – Under $500
✅ – Double Wall Rims
✅ – Pegs
✅ – Fully Sealed Bearings
✅ – 3 pc. Cranks
✅ – Freecoaster
- Full Chromoly
- 48 spline cranks
- Double wall rims
- 4 pc. Bars
2020 Fly Proton Overview
The Proton now features full 4130 Chromoly 4-piece bars along with full 4130 Chromoly 27mm offset forks and a taller 9.25” standover height frame, giving the bike a better overall look and feel. On top of that, the 2020 Proton comes equipped with a cassette hub, four pegs and a short and responsive 13” rear end perfect for all of the street riders out there.
2020 Fly Proton Specs
|FRAME MATERIAL: FULL 4130 CRMO|
|WHEEL SIZE: 20″|
|TOP TUBE LENGTH: 21″|
|CHAIN STAY LENGTH: 13″ – Learn About Chain Stays Here|
|HEADTUBE ANGLE: 75° – Learn About Head Tube Angles Here|
|SEAT TUBE ANGLE: 71°|
|FORKS: FULL 4130 CRMO / 1 PIECE STEER TUBE / 28MM OFFSET|
|BARS: FULL 4130 CRMO / 9″|
|STEM: TREBOL TOP LOAD / FORGED / 6061-T6 ALUMINUM / 50MM|
|HEADSET: INTERNAL SEALED BEARING|
|BRAKE MOUNTS: Removable|
|BRAKES: TREBOL SPRINGHANGER / FORGED / 6061 T-6 ALUMINUM|
|FRONT HUB: TREBOL BUENO / SEALED BEARING / 3/8” FEMALE AXLE / 36H|
|FRONT RIM: TREBOL / DOUBLE SIDE WALLED / 6061-T6 ALUMINUM / 36H|
|REAR HUB: TREBOL / SEALED BEARING / 14MM MALE AXLE / 36H / 9T|
|REAR RIM: TREBOL / DOUBLE SIDE WALLED / 6061-T6 ALUMINUM / 36H|
|TIRES: TREBOL 2.35 FRONT & REAR / 60 TPI / 65 PSI|
|SPROCKET: TREBOL / CNC MACHINED / 6061-T6 ALUMINUM / 25T|
|CRANKS: TREBOL 3PC / 4130 CRMO / 175 MM ARM LENGTH|
|BB: MID / SEALED BEARING|
|PEDALS: FLY RUBEN GRAPHITE / NYLON – FIBERGLASS COMPOUND|
|SEAT: FLY PROTON TRIPOD / 100% SYNTHETIC LEATHER / 25 MM THICKNESS|
|WEIGHT: 11.2 KG / 24.6 LB|
A: Top Tube Length: 21″ – Learn what size is right for you here.
This is a long top tube. Perfect for tall riders.
Perfect for riders that are between 5’10” to 6’2″
B: Chain Stay Length: 13” – Learn About Chain Stays Here
This is a medium chainstay. Designed to make the bike more responsive and snappy.
C: Head Tube Angle: 75° – Learn About Head Tube Angles Here
Steep head tube angles make the bike “snappy” meaning more responsive to fast turns.
A less steep head tube gives you more control.
D: Seat Tube Angle: 71°
E: Bottom Bracket Height: 11.75″
F: Stand over height: 9.25″
This is a taller standover.
A tall standover gives you more stability and will make bars, and t-bogs easier.
2020 Fly Proton Price
A complete street machine for $580 makes it one of Fly’s cheapest completes. But is $580 actually cheap? It really depends on who you ask. When I was getting into BMX and looking for bikes this would be wayyyyy over budget. I was broke though.
2020 Fly Proton Quality
The 2020 Proton is a High-quality complete bike. Full Chromoly and double-wall rims make it a great bike. However, Fly added a few other aftermarket parts to make this bike really stand out.
Fly Tractor Sprocket: An aftermarket sprocket that is thicker than most.
Volcano ST Stem: The brand new Volcano ST stem comes with a shorter 48mm reach and a taller, more street-friendly 35mm rise, to make your ride not only ultra-responsive but also amazing looking too.
Solid for street riding
Like I mentioned before, the 13″ chainstay, 4 pc. bars and freecoaster options make this a street machine. With this Proton, you will be able to do a new variety of street combos while progressing fast.
The only downside that I see is the over $500 price point. And to be honest, for the amount of quality $580 is still a good deal.
Buy if you are learning:
- Any Trick!!!
- Especially street stuff.
Don’t buy if you are learning:
- Solid for any kind of trick
2020 Fly Proton Conclusion 🤩
Even though the Proton is designed for street, you will be able to ride anything with it. The specs are designed to help you progress faster with street tricks, but the bike will hold up really good in the park or on dirt. I recommend this bike for a mid-level rider that want’s to take their bmx bike quality to the next level.
Frequently Asked Questions
This bike is great for riders between 5′ 8″ to 6′ 2″
This bike has crazy quality and I think it will last most mid-level riders a while. Probably two years.
Really good bike and a really good price. Fly makes good stuff.
The Fly Sion weighs about 24.6lbs
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