The XV sidecar - start of making a sidecar subframe and a plethora of other things (pt. 5)

Let's start with the biggest morale booster aside from firing up a bike for the first time and that's being able to sit on it for the first time. 

 

Assembling the bike up to a certain point has definitely been necessary, but the fitting of the tank (when the picture was taken) was hopelessly premature. But then again it felt incredibly good to sit on the bike.

The sidecar-swingarm-wheel-axle is about the right length and also 20mm so the wheel went straight on.

Laying out the sidecar - I wanted to stay within a track width of 1200 - 1300mm, sidecar wheel lead of about 300mm and about 15-20mm of toe-in.

The numbers achievable without any incredible handstands are 1280mm track and a lead of about 320-330mm. Toe-in will be set once the actual bike is built, but I plan to build it with 0 frame-wise, so I can set it up as I please once it is done.

Next job was to tram my milling vise and make the first bits in the lathe and mill. 

Added some pads to have more contact-area between frame and subframe-mounts.

Obviously the roundstock needed some flats for the nuts to sit on.

The adapter installed on the front cylinderhead.

Originally I wanted my bends to follow my engine very tightly, but to be fair, it would probably have given me next to no benefits in rigidity and less more work and the problem areas with the exhaust would not have been addressed this way.

I said, I wouldn't TIG-weld the subframe and guess what... here I am happily TIG'ing away.

Just to give you an idea of the size of my workshop... that's a 3m bit of tube. Cutting stuff got a bit tricky at times.

And here's one of the two downtubes (test-)fitted to the adapter.

The lower mount will be included (boxed in) into the downtubes. Due to lockdown I had to turn down 35mm roundstock to 24 over a length of 130mm. Definitely not a fun job as due to the cold the belts in my lathe are rather slippy.

Then I realised that in order to work out where the rear lower sidecar mount would go, I would have to fit the mufflers as it feels like everything is fighting for the same spots on the bike.  

In the past, I would simply have cut off a bit of M8 all-thread, drilled and tapped my mufflers and then welded them in. But not this time. Now as you surely know, stainless has the nasty habit of eating taps for breakfast and my M8 tap is as dull as can be. So I drilled 6.5mm holes (after fruitlessly trying to tap into the exhaust) and turned the stubs to 6.55, so they would be a gentle press fit and then welded them in. 

 

 

And there you go. She's looking more and more like an actual motorcycle every time.  

So what's next?  I need another spacer for the lower front mount on the other side and then this section can be completed rather quickly. After that the sidecar frame will (for the first time) get attached to the bike and then I'll see what the lower rear mount has in store for me. Lower frame and center-stand will undoubtedly need a modification and now that I know how the lower front mount is supposed to work I know I will be able to fit an oil-pressure sensor to the engine case. (I dreaded it would get in the way of the spacer.) Unfortunately this means the engine has to come out once more and I have to do some aluminium welding to fit the bung.