ConTENtious

[CRASH]

For some reason, I’ve had a bug up my butt to build a 10 speed muscle bike. There weren’t many 20” versions, so I decided to make something up.

When I do resto-mods, I try to make them look like the “should” have been made, but were overlooked. So whatever I come up with, I want it to look “correct”.

So I’m going to dig stuff out of my pile and see what I can come up with.

 

[CRASH]

I had to shamelessly steal a “before” picture from TRM.
This is an Eliminator twin stick shifter. One side is a 5-speed click shifter, and the other side is a drag brake.

Years ago I bought the derelict guts from @kingfish254 to get one part I needed. I kept the rest just because. Today I have found a use! I also have another broken Eliminator shifter I’m going to work on restoring at the same time.

I am going to try… no… I am going to SUCCEED in making the second arm a front derailleur shifter.

This is what I’m starting with.

 

[The Renaissance Man]

Here's another one for you.

 

[CRASH]

Thanks @The Renaissance Man. I'm pretty familiar with them, as I've restored a few. If you have questions... ask. (In this post because I'm not talking in the other one. )

 

[MattiThundrrr]

In this post because I'm not talking in the other one

"It's not fair!"

 

[CRASH]

The muriatic acid tub is freed up, so in goes this console.

 

[CRASH]

Wanted to do something a little custom for the bars on this one. @deven_science runs Alchemist Custom Bicycles and does great work. He’s a retired steel working Seabee Chief, but despite that flaw, this retired aviation Senior Chief thinks he’s tolerable. Anyway… Deven dove in to try some custom work for me. We talked about the bars of the type, and I gave him artistic license to design something. I think I went nuts with my imagination, but Deven kept me in check and designed something simple, era appropriate, and cool. So these are going on.

 

[The Renaissance Man]

Crash & Alchemist Custom Bicycles

That's a high standard of excellence!

 

[CRASH]

So I dove in to what might be the toughest part of this project. Creating a front derailleur shift arm for the Eliminator twin stick console.
So I worked with my guys in my fab shop at work. My laser guru used the broken brake arm I have (notice it’s missing the “prong” that grabs the brake knarp.) to draw up a simple design for the laser. We used some scrap metal and cut these out.

Then we got them on the press brake to get the right bends in it. The first piece was sacrificed because it was screwed up, but the second attempt came out great. It’s the one on the left.

For the shift cable portion, I sacrificed an old shift arm.

I cut it down and removed the pressure plate for the click bearing.

I cut away some excess to make it line up better with the arm. Here is is lined up. I stacked 3 washers to fill in that void.

And all welded together.

I had to do a lot of belt sanding to thin out the cable router. It was too thick to squeeze into the twin stick assembly.
Not pictured, but I had to have a very odd size washer fabricated to make the assembly work… but I think it’s going to work. Here’s the whole thing mocked up.

 

[CRASH]

Here’s how it looks in my other cover.

The challenge will be to design an indicator that looks like it was meant to be. The rear derailleur indicator is accomplished via a painted metal strip that is moved back and forth showing what gear the rear derailleur is in… which you can see through the cut out “window” It’s a bit complicated and I can’t reproduce it for the front. So I think I’m going to have to use a simple pointer that I’m going to attach to the shift stick.
I’ve got this cover out of here, so I am putting the cart before the horse and decided I’m going to design something right next to the shift handle, so it needs a window. So I cut it out.

And as you can see, following the muriatic acid and 50 years of abuse, this cover needed a lot of body work.

So after a long holiday weekend of bondo and sanding… all the way down to 2000 grit, it’s as smooth as I can get it and ready for some new chrome.

 

[The Renaissance Man]

Very cool!

Have you considered ditching the ribbon indicator and making matching pointers for both front and rear?

 

[CRASH]

Very cool!

Have you considered ditching the ribbon indicator and making matching pointers for both front and rear?

Yes, as a backup if I cannot find metal ribbon strips that will work. I'm trying to keep it as authentic as possible, with the scenario that this bike "Could/Should" have been made. However, my front derailleur shift arm, and it's loose engineering/execution seems to spit at that. I am restoring a second Eliminator console with the drag brake arm, so I need a ribbon for that as well. So... I'm boldly pushing through with the hope that I can find a solution.

 

[The Renaissance Man]

How about a metal key chain tape measure?

 

[CRASH]

How about a metal key chain tape measure?

Being shipped. It says due next week, but it's in California already. I couldn't find one that small locally, so ordered from Ebay.

 

[The Renaissance Man]

Awesome! I hope it works!

 

[CRASH]

One of the proposed features of this bike is "Triple Brake Action". For the front I have a tall rat trap fork, so how do you put a brake on a rat trap fork? I was bouncing engineering ideas through my head because I also want to install a fender. But getting a caliper to work without interfering with rat trap might be tricky. What I really wanted was a drum brake, but I couldn't find one. Until I found one. A guy I know had one that didn't have the axle. So we struck a deal.

I didn't take pictures of the trial and error that I went through trying to figure it out. What I can tell you is that I ended up using a rear axle/races+spacers, but I used loose front hub bearings. The axle is extremely long, so I'll correct that in steps ahead.

But first... I'm going to tear it apart so I can measure for spokes.

 

[CRASH]

For the rear portion of the “Triple Brake Action”, I’m envisioning a double caliper set up like a Screamer.

Finding one for sale is… well… I’ve never found one for sale so… how hard can it be to make one? I’ve got a couple Excel Grand Prix sets, so, let’s see if I can make this happen.
FYI: my biggest concern isn’t building it, or getting it to fit the rear wheel with an unknown fender. My biggest concern as I’m coming up with this plan is that I’ll be using a brake lever for the front brake, so I’ll only have one lever for both rear calipers, and they’ll be actuated from two different sides.

So anyway…

To build the center, I’m using a 120mm M6x1.0 bolt and a spacer I got from work.

So I bored it out and tapped it, and set the end length to what a regular brake pivot bolt would be. Then I had it tacked in place.

So next is going to be the tough part… cutting in the spring guide. I’ll try that this weekend.

 

[barbedwire]

Reading thru your progress so far is fascinating, so much engineering creativity going on here... I am really liking the dual rear brake working off one Lever, that's how they definitely should've been made on a Screamer!

 

[RustySprockets]

My biggest concern as I’m coming up with this plan is that I’ll be using a brake lever for the front brake, so I’ll only have one lever for both rear calipers, and they’ll be actuated from two different sides.

Hmmm... I'd probably be looking at modifying BMX gyro cables--they split 1-into-2 right out of the box. The problem might be length, since the lowers only run between the brake and the headtube. They may prove too short.

If you can find one long enough, it would provide an elegant solution. The lower units, like the one pictured, are typically 120cm/4ft in length.

 

[Captain Awesome]

Hmmm... I'd probably be looking at modifying BMX gyro cables--they split 1-into-2 right out of the box. The problem might be length, since the lowers only run between the brake and the headtube. They may prove too short.

If you can find one long enough, it would provide an elegant solution. The lower units, like the one pictured, are typically 120cm/4ft in length.

View attachment 247693

I was thinking the same

Otherwise look for a universal 2-1 throttle cable from a motorcycle/snowmobile shop. Not sure on the housing OD but those used to come in at least 4’ lengths. May require some cutting and soldering of different barrel ends but there should be an option out there somewhere