Building a ‘Straight Dangerous’ Dyna Drag Bike
Killer build quality and a clear plan promise to make this Dyna drag bike one of the quickest rides around!
Wild, custom Harleys are cool and all. But we also have a love for all things fast. After all, Harley-Davidson is known for building some pretty speedy bikes, both on tracks with turns and straight up drag racers. So when we came across HD Forums member SpaceReapersNOLA and his amazing Dyna drag bike project, we were immediately interested. A street/strip quarter mile maven? Sign us up!
“I thought I would start a thread detailing my newest project I’m calling “Straight Dangerous,” a Dyna drag bike built for the streets. I figure it is far enough along to start the thread and I will update as things get done. PLEASE keep in mind that this is a purpose built street drag bike. All design decisions are made with one goal in mind – going really fast 1/4 mile at a time.”
The OP is no rookie when it comes to building fast bikes, either. His previous 2003 Dyna pumped out 135 hp, yet had issues getting all those ponies to the ground. So this time around, the first order of business involved making the new Dyna hook like a proper drag bike.
“First thing we did was take the front end off and replace it with an inverted front end from an 09′ Yamaha R1. I had a machine shop make a custom set of triple trees to mount up the front end and will be running the R1 wheels, brakes, controls etc. I chose the R1 wheels specifically because of their light weight, easy availability and awesome braking power. If you go fast you gotta be able to stop fast.”
Right off the bat, this Dyna was already looking like the business. But there is some science behind the parts selection as well.
“Up next we got a Brocks Performance aluminum swingarm. This beast is 8-11” over stock and accommodates the 200 rear tire and R1 wheel with the 28mm axle. I had a nice conversation with Brock Davidson from Brocks Performance. He told me a neat little fact – for every pound of rotating weight you take off the wheels, it equals 7 pounds of static weight loss on the bike. So going from a stock Dyna rear wheel (which weighs in at 51 lb with tire, rotors, axle, etc.) to an R1 wheel (which weighs in at 35 lb, there is a 16 lb difference. That’s the equivalent of stripping 112 lb off the bike! The aluminum swingarm, even at 11 over stock, weighs 6 lb less than the stock length Dyna swingarm!”
Unfortunately, an issue with the OP’s other bike siphoned much needed funds from the Dyna project. But that didn’t dampen the enthusiasm.
“So now, in the middle of this project, the cam bearings on my Road King decided to take a dump and take the whole bottom end of the motor with them. So what would be the smart, reasonable thing to do here? You guessed it, get an S&S 124 kit for the Road King, add a chain conversion, and send the swingarm off to RB Racing for their conversion.”
This obviously slowed down things on the Dyna dragster, but it’s still making progress.
“The Dyna is currently at my good friend’s shop Royal T Racing. It’s getting a custom gas tank and tail section built for it. Pat and Luke formally worked for Jesse James at West Coast Choppers and their fab skills are unbelievable.”
And the OP has a clear goal in mind for both builds.
“I am still hoping to have both bikes up and running and testing by the end of February for a Harley vs. import race down here in Louisiana. Up next for the Dyna, we will be adding a BDL belt drive open primary, custom set of mid controls, air shifter, Ohlins shocks, ceramic wheel bearings, and trying to get it on the road. Once it is rolling we will start to try and get more horsepower out of the motor.”
It’s early, but we’ve got a feeling this Dyna dragster is going to be one seriously fast ride. Judging by the quality of the work done so far, it’s also going to look the business. You can (and should) follow along as this bad boy comes together by heading over here!
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