BMW Chopper for Born Free Part 2

If you had been following this build on Instagram and Facebook you will have a pretty good understanding of the effort I have been putting into it.

I have really focused a lot on raising my personal fabrication standards with this bike. Writing the ETS Fabrication School content has definitely helped!

The biggest change has come from writing and filming the ETS Fabrication School courses, I learnt a lot of theory behind what I do and I also set my workshop up to be able to do it on another level.

I am just finishing up the TIG course and through the extra understanding of the theory it has lifted my ability to weld chromoly like this.

The frame is a thing of beauty, the way the motor mounts into the frame and the frames lines produce a really good looking profile.

All of this productivity was necessary as BMW had planned a launch night to display the bike. Leading up to this event I worked 16 hour days for a week and a half and then a 38 hour day leading up to the bike being shipped.

Taking the bike off the jig was a huge moment for the project and made easy because of the 3 stage engine mounting system. I have a set of engine mounts that mount to the frame and then those frame rails remove from the frame via a pair of Camburg links to make a strong and uniform joint.

Whilst the frame was bolted to the motor in the jig I was able to complete over half the welding wich made the frame strong enough to then bench weld to complete the 360 degree welds around all joins.

The straight through Titanium pipes measure 1 7/8″ and have a wall thickness of 1.1mm, I love welding Ti and it really is just like any other metal, lots of argon (purging inside) and cleanliness are key to good results.

The more I strip off the motor the more I love the shape of it, the black combined with the billet aluminium, titanium, chromoly and the magneto belt drive setup with the dry sump pulleys harks back to my love of vintage drag racing.

The negative space under the gearbox is now full of brake and electrical components.

The reassembly process of the frame onto the motor went extremely well.

The workshop is a dream come true, tools at arms reach and everything fitting perfectly.

With the carbs on, brake master cylinders incorporated into the rear engine mount and reservoirs on it begins to take shape.

These Smart Carbs are a thing of beauty, the foot pegs are also attached and these have bronze bushes that will form the pivot point for the brake and clutch.

When I first started to get interested in choppers it was the simplicity and the slim nature of them that I loved, my plan with this bike was to accentuate the size of the engine by building a slim bike around it. I think its working!

I had planned to partner up with Volumetric in NZ to Carbon print a pair of intake velocity stacks but after sitting some titanium on the inlet side of the motor and seeing that flow of titanium- billet alloy carb- billet alloy rocker covers- into titanium exhaust I just fell in love with the aesthetic. So 28 hours into my work day I decided to make some up out of 2.5 inch titanium. This required a mandrel to be made up to expand the inside diameter to suit the carbs. I jumped on the lathe, machined a small taper into some 65mm barstock and pressed the tube over it in the press. (you can see all of this in my Instagram highlights)

The rear drive unit comes from the stock R9T I pulled apart to build this bike, its matched perfectly to the engines output and gearing so I really didn’t want to mess with what is a very well designed unit. I made the frame hug the drive unit and I believe it looks right at home. I machined up the driveshaft and then welded it together and assembled the universal joints to suit.

With the pipes and the rear fender attached and the bike is looking amazing!

The mix of raw metals on the bike looks incredible, stainless steel, titanium, chromoly and aluminium all in their raw state and all welded to the best of my ability. This was about 32 hours of work non stop, yep I was getting a little wired!

This tank came from the good people at Lowbrow Customs in the USA and after I removed all the mounting tabs it floats and looks great on the frame. I came up with a really neat internal mounting solution also depicted in my Instagram highlights.

From the rear I am over the moon with the semi finished product.

From the front I am even more excited. I can’t wait to ride this!

With BMW arriving in just a few hours I had just done a straight 36 hours working on this, I didn’t rush anything, I took my time and concentrated on each and every weld, made sure everything was laser aligned and the bike went back together better than anythin g I had ever made before.

With the bike delivered to the BMW launch I was excited to see its progress as were many others, I love building things, I love challenges, I love sharing the process and teaching people along the way, I had definitely pushed myself further than I ever had before with the hours I poured into this build so far and I think it shows. With the Born Free Show in the USA looming and the global climate making everything more difficult I am hopeful this bike will continue the way it has and get the grand treatment that it deserves in the USA. I just really hope I can still travel with it.

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