Project Delta – Royal Enfield Super Meteor 650 Build Release

We have a sharp focus on consistent progress, and have held fast on the idea that if we stop moving forward, we will cease to exist. The reason I wanted to share this, is that because of this drive we sometimes hit a milestone that is worth stopping and taking note on. Reminding us of how far we’ve come. Project Delta is that milestone. Named after the Purpose Built Moto Delta, that represents a value of constant change.

When we were contacted by Royal Enfield to create a motorcycle based on their Super meteor 650, I wondered “why us?” I soon realised it didn’t matter why, the only important thing was we took this opportunity and ran with it, showing just what we’re capable of doing when given creative freedom and control over the outcome of a build in its entirety.

The Concept:

As we often speak on, our build ideas come from our relationship with the client, their personal tastes, the ride style they like and the energy they put out in our meetings and consult on their bike. Building for a manufacturer was a little different, as there was no one person we needed to get to know, I took a look at Royal Enfield as a company, poured through their history, and took their current messaging and community into account. “What are royal Enfield trying to build?” was the question.
My answer, was they have cultivated a die hard community of riders based on their unwavering commitment to heritage throwback motorcycles. The Royal Enfield range is void of cutting edge performance motorcycles, the latest technology and future driven design, yet the riders on their bike don’t seem to care. A Royal Enfield rider is in it for the experience of nostalgia, and the soul they instil in their motorcycle.

A perfect example of this is my friend Dave, He rides the Olive Green Royal Enfield Bullet 500 built by PBM in 2022. He’s done very well in his career and drives a number of classic exotic cars, expensive stuff. His motorcycles are another story. A 1970’s TT500 and a Royal Enfield Bullet 500. Why when he could afford any motorcycle he wanted, does he choose these? I asked him point blank, why don’t we build you something a little more Exciting? “What’s more exciting than a kickstart thumper” was his answer. I couldn’t argue with that, you love what you love.

Taking lead from Royal Enfield’s history we would craft a motorcycle that Was inspired by a very simple time in motorcycling the 1940s-1950s. Looking at models like the original Super Meteor 700, and one of my personal favourites the flying flea from World War 2. Delivering a classically styled motorcycle and a more visceral raw ride feel, just like you got on a Super Meteor from 1952.

The Idea:
To make the concept happen we would focus on a few first principles in our design.

Removing weight both visually and physically
Creating a more classic style riding position
Simplifying the silhouette

These 3 things if executed right would transform the Modern Super Meteor 650 into a Vintage styled roadster, and in turn make the motorcycle a unique experience for any rider. All while showcasing the incredibly styled Royal Enfield 650 power plant.

Our hit list of modifications included a custom front suspension, heavily modifying the frame and rebuilding the entire rear section, hand made body work, tank shift/hand clutch and a floating bobber style seat.

The Teardown:

The Royal Enfield 650 twin family has a number of different styled models built around the engine. The continental café racer, The Interceptor street scrambler, The Cruiser style Super meteor and Shotgun, and most recently the more Off-road focussed Bear 650. All models tied together by their 650 hearts. An oil cooled 270-degree parallel twin that put our just shy of 50HP and a little more than 50Nm of torque.

As the brand new Super Meteor was delivered we needed to uncover what was beneath the shiny exterior and get to the core of this bike to build upon that foundation. Everything was stripped to leave a rolling chassis and engine combo that would form the basis of our build. Everything else would be custom fabricated to realise our vision of what the Super meteor could be.

The Chassis:

First order of business was to get our wheels on the way, using a 23” clincher front tyre and 19” rear. This change would help create a more vintage board track style stance on our machine. Using a Continental rear hub on the rear and a universal single disc hub on the front we could build our new front end and swing arm around these.

While waiting for the specialty rims to be hand made and chromed, we moved on with frame mods. Oil coolers in their modern form didn’t appear on bikes until the 1970’s, so we wanted to remove this in favour of a more vintage styled approach. We’ve rebuilt the front engine frame rails and used an oil in frame set up. Detailing the tubes on the lathe to carry our styling details through the build. This modification isn’t as efficient as a modern oil radiator, but it cleans up the front of the bike amazingly well and works a lot better than a straight bypass. With this work also came a re-styling of the neck removing the heavy cast bracing in place of some neatly fabricated gussets.

This also slimmed out the back bone of the frame that would allow a tight fitting custom tank to be fabricated down the line. Next onto the rear of the frame. Traditionally the Super Meteor was a twin shock motorcycle with the classic loop frame style the Royal Enfield’s were famous for. In the interest of lightening the bike, we’ve removed the rear section of the frame leaving only the engine mount and swing arm pivot to create a direct drive monoshock suspension set up. Saving us around 12kg in frame weight with a few cuts. The swing arm was built around some new axle plates that we designed and machined for the build. Using lightweight chromoly tube and some stainless steel detailing in the brace section the Monoshock conversion was finished with a custom built Nitron shock. The end result is a drastic change in the silhouette of the Super meteor that delivers a far more vintage side profile for the build.

The Girder:

Something I’ve wanted to build for a long time, and a perfect fit for this project was out custom Girder fork. Used on bikes from the 1900’s through to the 1940’s the principle of a girder really lets the builder get creative with the lines of the bike. This sort of work is also my favourite to do, designing a functional and pivotal style piece on the bike. Making something that elevates the style, but having to make it work well too. I took inspiration from the Girder design on the flying flea, added my own style choices and tweaked it to fit perfectly with the design elements of our build.

Starting with a 3D model in my cad program to get our dimensions + geometry correct, the model was broken down into individual parts for manual machining. Using a 1:1 scale physical print out to get my sand bend radius tubes and spigots aligned correctly. Making each side before welding the fork together with the cross bracing. We’ve used a downhill adjustable air shock for the suspension movement, linking the girder to the yokes with a set of stainless-steel dog-bones fitted with needle roller bearings.

Then machining the top and bottom yokes for the head-stem and beginning fabrication on the single piece handlebars and mount. The bar design was taken directly from a 1951 Royal Enfield Bullet 350 we have recently restored. The flat profile sits the rider upright and the reverse curve creates a beautiful outlook over the cockpit as you ride.

The Seat + Tail:

With the bike under its own weight and the new vintage style tyres fitted, project delta was coming to life. With the ultra slim profile on the rear, we wanted to keep things simple. Adding some shape to a reverse lip fender, we have finished the fender with a set of stainless steel fender struts and our new Deco rear fender light. The fender light base gets welded to the fender and the hidden cable routed away under the fender.

The tail light is modelled after 1930’s art deco Guide lights used on the front of motorcycles and cars. Tear drop shaped with a patterned cast lense. The seat is trimmed out in a vintaged cherry red leather, that was paint matched for the pinstriping. Jamason from timeless autotrim bought this design to life and used a heritage Royal Enfield logo that’s been laser etched into the seat sides. We’ve also laid out matching leather grips on the handlebars and tank shifter.

The Tank and Shifter:

A hugely important element of the design was the tank. Hand made aluminium styled to match the shape of the 50’s model Super meteor, with a reduced size to allow the engine to protrude from underneath and keep the slim profile of the bike intact.
Shaped from scratch by Cody as one of his first big jobs in the shop. A real challenge fitting the fuel pump into this tiny little tank but it was done with no compromise to style.

Alongside the tank is the hand shifter. Pivoted off the inspection cap on the stator cover, we’ve made the bike a hand clutch, tank sift configuration to keep to bars clean and add a bit of custom flair and novelty to the ride. The brake and clutch levers, as well as the hidden master cylinder all come from Kustom tech Italy.

The Exhaust:

Our hand built stainless exhaust gives the Super Meteor an ultimate growl. A note you can only get out of a 270 deg parallel twin. Making the fishtail style mufflers was a process I had in my mind from the beginning. After sand bending some sections of tube, splitting the bend down the middle and using a wedge piece to create the shape, the design allowed us to get the perfect note out of the bike with an internal muffler, and match the art-deco styling on the bike.

The Intakes:

On a recent trip to Greece I walked past a very interesting workshop in Athens. After a few minutes looking in the window I was invited inside by Michael and his father who has been metal spinning for 50+ years. We spoke about their craft and history in this small workshop, filled to the brim with hand spun ornate shapes. I asked if they could teach me some things and they kindly obliged me for a few hours shadowing them in the shop the next day.
They created the spun brass velocity stacks on this bike while teaching me and letting me had a go with some of their special tooling. Aesthetically its an amazing piece of the project, but to have a great memory behind this particular part makes it even more special.

The Paint:

Our paint design needed to be simple, letting the fabrication and design work do the talking and letting the shape of the bike shine. We sketched out a design that included some filigree detailing to be done in Gold Leaf and pinstriped with a matching cherry red from the seat leather. Justin from Popbang classics took the idea and ran with it on the paint work, and turned out a world class finish with the hand laid details and pinstriping. The tank wears the heritage Royal Enfield Logo, and of course the Purpose Built Moto signature.

The Ride:

With the work we’ve done the Custom super meteor is drastically different from the bike we’ve started with to ride. Lengthening the wheel base, building the front and rear suspension and using the 23” wheel creates a stable ride at speed. The comfort and ease of the factory super meteor is replaced with a complex and novel ride as you shift through the gears with your left hand. The ergonomics and cornering are indicative of a true vintage machine. And through the solid mount bars and girder fork you feel the road beneath you. Receiving constant feedback from the rumbling engine, the floating seat and tall wall rear tyre.

Although the super meteor is far from a traditional ride, for some reason it inspired confidence on the test ride, enough so to wind the bike out as fast as it would go, I stopped looking at the speedo and focussed on the road as it climbed past 160KM/h on a quiet back road. Trees blurring by and the wind pouring through my open face helmet as my eyes started to water. Winding off the throttle and coming to a stop taking note of what we’ve built. Until a motorcycle is tested like this it isn’t really finished in my eyes, the Project Delta delivered one hell of a first ride experience and I can’t wait to get to know her more.

This build put a stake in the ground and represents a shift in gears for Purpose Built Moto. Through our time we’ve built a unique skill set in the shop, that is now allowing us to create motorcycles on a higher level than we ever had before. From here we aim to push further with the re-design and engineering of our motorcycles. Creating truly one of a kind machines, rather than just modified motorcycles. You will still see the customs you love from our shop, but we will be exploring our frame up builds more in future. We hope you enjoyed this in depth run down, and if you want to see the build being pieced together go and check out our build series on Youtube.