Φ Bultakenstein [Aborted]

The Frontera 360 “bottom end” I bought arrived, and it’s much more complete that I had expected. It’s basically a complete motor, minus the barrel, head and clutch plates. It even came … A surprisingly complete engineRead more

Slowly making progress on the frame. Lots of measuring and nudging lately, not much fabrication. I did chuck up some aluminum in the lathe and made spacers that positively locate the swingarm … Gettin’ jiggyRead more

I am picking up some additional engine parts, in the form of this Model 143 Frontera 360 bottom end. It has the larger cylinder opening of the big bore (326–363cc) bikes, the … A larger engineRead more

I got the jig assembled yesterday, though I still need to attach the legs (the smaller tubing crossways under it). I have four threaded leveling feet (in the McMaster-Carr baggie). I also … Frame jig assembledRead more

I was down in the basement this morning and moved Bultakenstein’s rear wheel out of my way (yet again). I happened to check at the date stamp on my rear tire: 4310. … Use it or lose itRead more

I just ordered Chop Source’s “basic” frame jig kit. Essentially I’ll have what’s shown in the photo, minus the center cradle supports and transverse legs. The center part I really don’t need, … Frame jig on its wayRead more

My twin-shock swingarm arrived yesterday. It’s not quite the bolt-up replacement I was hoping it would be, but it will work if I decide to go that way.Compared side-by-side, the DT175 swingarm … Swingarm comparisonRead more

So, a few months back, I happened to find this photo of a converted Bultaco Pursang on the web. Looking at it, all I could think was that if I had simply … Abandon the monoshock?Read more

I finished the four frame lugs, cut the tubing to length, and mocked up the seat loop. I’ve decided to have it professionally welded. Unfortunately, my neighborhood welder can’t get me in … Seat workRead more

I was looking at some of the smaller ball and needle bearing sizes on McMaster-Carr’s website. I’m thinking of using these self-aligning, flange-mount roller bearings to mount my shifter crossover linkage. Less … Self-aligning flange bearingsRead more