from Rookie’s keyboard
Hello, friends
Today, I am going to talk about BMX and suspension. I decided to make this post after a reader sent me an e-mail. BTW, thank you, Nick. I appreciate all e-mails – positive and negative.
Let’s go, fellas.
The reality is this:
You can’t equip a 20″ BMX with a basic suspension fork because it will destroy the geometry of the bike.
Front shocks for 20-inch wheels are either custom-made and rare or designed for children’s mountain bikes and unable to sustain BMX type of stress.
But if for some crazy reason, you want to have a BMX-like bike with suspension, look into 24″ and 26″ dirt jumpers.
Negative Changes to The Geometry
BMX frames are designed for a rigid fork. If you install an after-market suspension fork on it, the conversion will result in the following complications:
Raised front end. If the fork isn’t engineered for a BMX, the front end of the bike will raise, and the headtube angle will become unpleasantly slack.
The maneuverability of the bike will suffer, and it will be very easy to “loop out” (the bike sliding in front of you).
So, just don’t do it. The bike will feel all wrong.
Even if the suspension fork is made specifically for a BMX, it can still create some issues because the frame itself won’t be built for a suspension fork.
When the fork compresses, the front end of the bike will get closer to the ground. The head tube angle will become steeper, and the rider’s weight will shift forward.
On a frame engineered for suspension, this isn’t a problem because the headtube is high enough.
But in this case, the outcome could include an accident such as getting over the handlebars.
This outcome can be prevented if the suspension fork and frame are engineered to operate in a union.
The frame needs to have a taller head tube than normal so that the HTA doesn’t get dangerously steep upon compression of the fork.
At the same time, the fork shouldn’t be excessively long so that the HTA doesn’t become uncomfortably “slack”.
Low Availability
Good luck finding a decent suspension fork for 20″ wheels. Most of the offers are either custom, rare, and expensive or taken from kid’s mountain bikes. A fork from a kid’s bike cannot cope with the stress that an adult rider would put on it.
Tricks Become Trickier
A suspension fork complicates the execution of some tricks. For example, it’s a lot easier to perform a nose manual with a rigid fork because you have a stable base underneath you.
Lower Road Sensitivity
A suspension fork absorbs the irregularities of the road. This is beneficial for mounting biking, but when it comes to tricks, the absorption is negative because it reduces sensitivity and the “connection with the ground”.
Bad Habits
A rigid bike teaches you how to absorb landings without counting on suspension. Thus, in some regards, a suspension fork could be seen as a crutch.
Heavy
Suspension forks are heavier than rigid ones due to the extra parts required for the proper operation of the shock.
Weaker
Suspension forks aren’t nearly as robust as rigid models. One has to be extra careful not to scratch the stanchions because they can deteriorate.
Also, a suspension fork needs frequent servicing which includes replacement of the suspension fluid, the lubricating oil, the foam rings, and the seals.
Alternatives
If you want a street BMX-like bike with suspension, 24″ MTBs are a good choice. They offer the following pros:
Suspension-friendly Geometry
Unlike standard BMX bikes, 24-inch MTBs have a frame designed for suspension. As a result, the head tube angle doesn’t experience dangerous changes when the fork compresses.
More Choices
It’s notably easier to find a 24″ fork than a 20″inch one
Small Tire Size
tires are fairly small and preserve the “BMX feel” much better than 26″ models.
Extra cushioning + Greater Roll-over-ability
24″ which tires are still notably bigger than 20″ and ride over obstacles with greater ease
Extra Speed
Larger wheels preserve their kinetic energy for longer once you get them up to speed. Hence why 24″ inch wheels require fewer crank revolutions in between tricks.
Below is a list of 24-inch MTBs with suspension that are as close as possible to a BMX bike:
- Black Market Contraband
- Union Street Molly Maguire
- Specialized P.Street 24″
Did you know that? The most popular 20″ BMX suspension fork is Answer PRO FORX. The fork came out in the early 90s and was designed for BMX racing. Many of the professional racers advertising it were using a PVC elastomer which was essentially turning the fork into a rigid one.
Well, Nick, I hope this post was helpful and answers your question.
Until next time
– Rookie
Leave a Reply