Engine Plates

Let's start on the engine plates. I drove to two places looking for some 6061 plate as my 3' piece is now somehow 24". Second place I found some decent drops. $26 later I ended up using what I had left - sharing the diagonal cut helped. I will remove an inch or two off the bottom of the plates as they would drop well below the hypothetical "loop" of the frame plus they will look a little bulky below the engine block - I want to keep that pretty low slung in the frame. There will be four mounting holes(narrower than scribed) that will mate up with bungs on each of the tubes. I'm not sure if I'll wait on those till I get the frame tacked up or if the plates would help align the tubes. I will also add a tube to bridge the down tube and seat tube for added strength - it will be concealed under the plate. The Dykem wasn't really necessary at this point but the flashback to model airplane dope days alone was worth it! I also mounted the stock 26" forks just for kicks. I knew I would have to widen the crown and add an upper triple tree and trusses but I didn't think they would be that short. I'm beginning to see why many of the "replicas" look so awkward.

"Mockup of the frame"

The modified notcher is making great fishmouths now. Perfect angles are another story. I bought some larger size end mills in case I needed to touch up a few cuts but it may not be worth the extra time - they are pretty close. A friend asked today if I was going to braze it. Well, the notches aren't that perfect. I have considered making a tube holder for the cross slide of the lathe that would allow more precise notches but, again, I'd like to see how close this comedy of errors will be fitting basically by hand. Even modern frames are straightened at the factory after brazing so it should be fun trying to straighten this .120 tubing once welded! If I decide to make additional models I will have to build a jig and revisit the notching method. Anyway, here are a few pics of the main tubes. The top tube is missing as it has to be bent. A friend has "committed" to buying a bender soon so ......... he can use my stuff if I can use his right?(you know who you are - hint, hint) I didn't hit my lines well before the pic but everything is pretty close. The angles are what concern me the most. You can immediately see the gap where I will build plates to replicate the "Marion" frame under the engine. On the Indian and HD, the engine, after about 1915, was a stressed member on most racing models. These plates will carry the motor and then be mounted to bungs on the down tube and seat stay tube - same principle. Putting the earlier-style bend in the frame would leave little room for adjustment - something very much needed in this mock up.

Back on Track

Okay, some shimming and a little of this and...... Now we're talkin'. It is as close as it can be now but there is a strange twist in the body of the notcher. The piece shifts as you tighten the angle adjustment bolts............. I'm wondering if the bushings are even in line with the bearing block. Geez. I should be done by now!

Trouble?

Okay, anyone who knows me realizes that I cannot go too long without a rant about something - usually about something which bothers only me. In addition it is usually unprovoked and random. This time it's cheap Chinese tools. My parents started buying me tools when I was young - mostly Craftsman. Most of them I still have today. While I have worked around those who buy only Snap-On, Mac, etc., I can honestly say I have never broken a socket or wrench made by Craftsman, and believe me, I have tried! There are much more expensive and elite tools out there but even with misuse and abuse Craftsman have held up well. I have never even returned one for replacement. My point? Well, a lifetime guarantee is no good if you are replacing a tool every week - even if for free. Wait, that wasn't my point at all. Okay, the Chinese import boom and crap dealers like Harbor Freight, Cummin's, and WalMart have helped many people, who could not have otherwise afforded it, get involved in DIY projects using their cheap tools. It has also put some pressure on US manufacturers. Some stuff is passable and some is laughable. I have a HF lathe and a Grizzly mill - both Chinese imports. These would be examples of having "cheap" tools or never having any at all. Waiting to afford a Clausing or Bridgeport would put me close to retirement. For what they are, they are, IMO, when carefully modded and adjusted, "passable". But I'm no machinist! I don't mean to imply the "made in the USA" means it is always better. There is some real crap out there - it's a world market now and there is enough crap for all of us to sell. Back to the subject of this blog. A few weeks ago I picked up a tubing notcher at HF. It appeared to have a better mount than the earlier versions I had seen. I took it apart, cleaned it, lubed it, and adjusted it. I then mounted it to the drill press table using a center point in the chuck to line it up perfectly with the arbor. After a few more minutes of fiddling, I tried to make my first 50-degree fishmouth cut in the downtube of the BTR frame material - 1 1/8" .120 DOM. Am I the only one who sees this isn't going to work? This is not distorted from the camera angle. It was that far off! This thing is self-centering and will just need to be shimmed but it's really irritating that I have to spend half a day figuring out what is centered, figure the shim stock needed, go get some, and reassemble this thing just to get it to do what it is supposed to do. Dare I check the protractor? Not a chance. I knew better and never even looked at it. I guess my point is you get what you pay for - either in cash or your time (didn't I hear that before somewhere?). I suppose the Chinese to English translation was incorrect. It should read "Useless" or, in the King's English, "Crappy" Along the same lines, here is the rear of a Chinese-made mountain bike I cut apart. Again, this is no camera distortion. Not only are the seat stays not symmetrical to the post but the hole for the rear brake caliper is nowhere near parallel to the wheel travel and not even in the center of the tube - had to be hand-done. It all looked much worse on the bike. I wouldn't have let a clown ride it! Can you imagine if this entire project from beginning to end was done like this? Don't chuckle - it might be!

First Part Made!

This morning I turned out the head tube. Here, I'm cutting the 1 1/2" heavy wall tubing: Using the lathe, I faced each end and then bored each for the bearing cups: And finally the completed head tube:

A Few Authentic BTRs

These are all I can access at work right now. I'll add more later.

More Thoughts

I never revealed my true real-world intentions with this project. Do I want an exact replica museum piece? Do I want a nonassuming(yeah right) everyday-use moped? Who do I think I will fool? Where do I think I can ride this? What cop wouldn't pull me over? Ultimately, I want a discussion piece. I enjoy people saying, "What is it?", "Where did you get it?", "How did you do that?" "Why is this sitting in your house?" This is a huge reason we are into cafe racers - well, not the last one. I'm not near dillusional enough to believe I will have a bike that will keep up on today's roadways. I also doubt I will actually be able to pedal it far - the tubing alone weighs a ton. I am crazy enough to think I will learn more than I want to about making it work and learn how better to use my tools to make other bike projects. I need to get some rest but I forgot some pretty relevant info. This project is actually going to be about 1/93 scale. This is for several reasons. Cost is the ultimately consideration no matter the project or compromise considered - cost in time, cost in patience, cost in materials - all weighed against the usefulness of the end product. The cost of perfection is often not ever completing the project. Otherwise, do what Brodie did. Skill may be my greatest downfall there. 26" bike parts, new or old, are cheap. Cheap compared to motorcycle parts (and who has heard of a new 26" or 28" motorcycle wheel?) and certainly cheap compared to authentic antique motorcycle parts. I came up with 93% by first deciding to use a 26" wheelset. That left me with a standard or scale to use to extrapolate from an image of a true BTR. This gave me a place to start - What would the wheelbase be? The trail? Head angle? Chainstay angle? Dropout plate dimensions? About how much tubing would I need? Bla Bla Bla. This does nothing to reveal structural considerations - elasticity, yield strength, deflection..... I'm pretty much limited to what they came up with back then. I'm basically trying to find out what geometry they used, not what I think would be good, that's all. The rest is only for discussion's sake. This is yet another reason I went with the heavy wall tubing. If I changed the geometry to support the load differently I would alter the overall appearance of the bike. I won't be using cast lugs either. Fillet brazing isn't the same but a better fit for the project. One real comfort is that not much has changed in the world of bicycle geometry over the past 125 years. I'll have to trust that the design and relatively crude construction methods used then will allow me to at least go around the block and stay upright. Check out this board track racing bicycle of the 1890s: Precious little has changed in road bike geometry. Okay off to bed. Tomorrow I hope to cut something metal!