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Ulu

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This build is based on a Trek aluminum frame junker someone tossed out on garbage day. It was going to be a chopper build but I really don’t like these forks.
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This frame was covered in several coats of flat black paint and dirt, and last Summer, I soaked it in old brake fluid in the desert sun for about a week. 95% of the paint fell right off from the hot brake fluid, but there was lots of detailing to do.

This bike has taken some battle damage but it’s not too scarred up and there’s only a minor ding or two. Most of the ugliness was in the drop outs which had been severely over tightened and gouged.

I have this BMX fork that was with it, and it used to be a nice chro-moly fork. Now it is twisted, bent, and gouged.
B1D8515A-6F8F-41EB-90EF-AA030EF6C66D.jpeg

The handlebars and clamp were trashed and went into the junk pile. The seat post was wrong, and the seat post clamp ended up being this shifter body on the Lengthy Insanity.
EF72FAB6-529A-4995-8E2E-358AB9398BC1.jpeg


There was also a forged crank that was chrome underneath all the black paint, but the bearings were shot and the sprocket was shot. No pedals, no seat, no wheels. Just a rusty chain, perched hopelessly on a pile of junk, until I came along and scooped it up.

Aside from that seat clamp, the only things salvageable are the bare frame and the head bearing races. (Nope. I had to toss the head bearings too. They were junk. This starts with nothing but a frame.

EDIT:
Forget the BMX idea. This will be another musclebike.
(I am moving this stuff over from Ulu’s Bike Update.)
 
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Ulu

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It is raining, and it is the nicest thing that’s happened here in a while. We’ve been under severe drought for several years.

But it’s gloomy out in the boat yard, and the concrete is all wet, and here I am buffing the remaining paint off of this aluminum frame.
4AAD69D4-2CE3-42FD-90DF-159DA13B6271.jpeg


As far as I can tell there are no cracks and no dents but a few small pits. The welding looks really nice. I’m jealous.
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I just tied it down on my anvil and now I’m going to use the electric drill, nylon shotgun brush, and then a scotch bright wheel.

Most of the remaining paint has been emulsified by soaking it In hot brake fluid & fell right off when I rubbed it with a rag, but some areas were stubborn.
 

Ulu

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It has been raining on and off for two days now and I had to move my operations indoors. I have spent several hours now scrubbing this frame with scotchbrite and detailing it with little picks, and it’s starting to look pretty nice despite the numerous small battle scars.
4215D49F-2860-44E7-9754-C0EB02ABACB5.jpeg
 
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Ulu

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It looks like I still have several hours of Scotch bright buffing to get this frame nice enough to clearcoat. But it’s still raining so I wouldn’t be able to do that today anyway.

I don’t think I will use the stinkray forks on this bike. I have a 26 inch mountain bike fork from the fake Schwinn that will take this bike out of the muscle field and into the dirt field.

I have a battlescarred chromed forged crank and some bearings for this, and the cups are all OK. But I might try to convert this to a more modern sealed bottom end if I can get the parts today.
 

Ulu

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I have spent about six hours cleaning this frame and detailing the welds. It needs another few hours before it’s ready to clearcoat.
9AA293F8-910C-408B-9902-CD41600CEF99.jpeg


Every time I look at these welds I want to take up aluminum welding. Anyhow, I want it to look really nice so my grandkids will feel guilty when they scratch it all up on me.

I made it to the bicycle shops today and scored some new bits. An American-to-Euro BB adapter, an RPM sealed bearing kit, a new used crank arm, a new bell, and Shimano steel hardware kits.
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The arm & hardware kits are for this Shimano 600 bio-pace set.
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This has very long 175mm arms, and it’s just not really off-road gear, so I think this is going to go on my townie bike, and the townie is going to donate its more BMX-looking crankset to the Trek.
 

Ulu

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I pulled out the cups from the bottom bracket today, and they came out nicely. They are still in usable shape, but they are past their prime.

I used this gear puller and I made a bridge by smashing a little short piece of tubing. I backed it up with a thick flat washer.
C892A2F6-118B-4BD0-8CC9-3BED4BCA7722.jpeg



In action:
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When you do it this way, you don’t know which cup will come out first. As it happens, it pushed out the non-drive side.

Here is the drive side.
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To remove the other cup, I drew it into this big bronze nut. I’m sure you will all have one of these in your toolbox. It fits inside a 1959 American standard toilet. When I junked the toilet in 2017, I kept the bronze parts, which were still fine. Fortunately I never recycled the nut.

8AD992EF-1CF3-45EA-94C7-2F6A8C478C9E.jpeg


I don’t know where the clamp came from. Something in the Air Force. There’s an M10 bolt there, Which drew the cup out quite easily. The nut wasn’t quite thick enough, but one tap of the hammer finished the job.
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You can see the two mongoose cups and an old cup from the 50s that came out of my dad‘s toolbox. The 1950s cup has a longer land turned on it, where it touches the tubing but otherwise the new ones compare favorably. Not like those Chinese ones from the LOL bike.

I took a cut off wheel to the cable guides. I hate having exposed cable on a bicycle when it could be inside a housing, but this bike will have only a coaster brake.
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I masked it with heavy duck tape to protect the tubing. I cut it as close as I dared on the first go.
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And I started filing. I don’t have a die filer, so I just did it by hand with a mill file.
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The rear guide is completely gone now, and the front one is next. Coarse scotchbrite disguises everything.
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I think it’s time for a break.
 
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Ulu

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Fortunately this bike only had 2 guides. I cut them off and dressed the tube nicely.

I used the greatest possible care not to file the tube, but a tiny bit had to come off to remove all evidence of welding. It was only possible to make it look so nice, because the welding was just perfect.

That kind of work takes a toll on my hands and wrists. Particularly the precision filing. Thank God it was aluminum!
 

Ulu

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Well I think that I was out of my mind when I decided to do this as an off-road.

I started looking through my collection of stuff, and I have everything I need to build a chopper except the seat.

The only thing I have for BMX is the seat. The other BMX parts are all trash.

I thought the fake Schwinn forks that I had were going to work until I looked at the wheel and brake set up I have.

It’s a No-go, plus I don’t have the controls. Not even the seat post will work.

Yet all that stuff I could get, and I would, except for three things.

The brake anchor set up on this frame is ruined.

I’ve already cut off the guides.

I’m only building this because I have almost everything I need already.

To build something that is. Not a prize-winning bike of any sort, but something useful that didn’t cost much.

The simpler it is the better. My grandkids are gonna ride this, and I don’t need trouble. I’m already afraid they are going to fight over the other banana bikes.

So about the time everybody gets used to this being in the off-road category I’ll probably kick it over to muscle bikes.

(Edit: and here it is…)
 
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Son of Kradus

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some great use of tools available removing them race's, and that ally welding..I too have fallen for the premium ally welding and am wondering if that work on your frame is a machine job or craftsman!
 

Ulu

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I had to straighten out the seat mast where the tube in caves in at the top from overclamping the wrong seat post. I don’t have the correct post or clamp.

The inside of the tube was gunky, and I cleaned it out first with the electric drill and wire brush, but I couldn’t get very deep (not even halfway) so I resorted to this drill extension with a brake cylinder hone to clean out the entire tube.
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I was surprised at how much dirt and crap there was in there.
E088021B-48E5-4E28-AA65-9E59D06C64F0.jpeg
 

Ulu

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Well now I don’t even have a BMX seat.

My sister brought her bicycle over today and I gave her my seat to replace the pitiful excuse on her bike.

Anyhow, I decided to see if I could set this up with the 26 inch mountain bike forks and the 16 inch front wheel. Then I decided to blow my cover completely and put the ape hangers on it.

725C3DCF-91E6-4602-AD59-F86733485FD1.jpeg

I sure hate the look of those modern round shouldered forks, but they are strong; and they were free because they’re from my junk pile.
 

Ulu

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I started to put in the American bottom bracket adapter kit today and I realized at that time that this has to be pressed in place, and it has to be indexed so that both sides match, otherwise you can’t get the little screws in.

I’ve got a ball joint press kit with some press plates that should fit this, but if not I’ll come up with something. Any old flat plates with a hole in them would work except that you cannot see the index mark while you’re doing it.

Also I never considered the fact that these are aluminum and I am going to be pressing them into an aluminum frame. I don’t want the aluminum to gall together, so I’ll put some grease or some anti-sieze on it first.

I think if I warm up that bottom bracket with the propane torch it will give me enough clearance that these things will slip in with a mallet tap.
 

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I started to put in the American bottom bracket adapter kit today and I realized at that time that this has to be pressed in place, and it has to be indexed so that both sides match, otherwise you can’t get the little screws in.

I’ve got a ball joint press kit with some press plates that should fit this, but if not I’ll come up with something. Any old flat plates with a hole in them would work except that you cannot see the index mark while you’re doing it.

Also I never considered the fact that these are aluminum and I am going to be pressing them into an aluminum frame. I don’t want the aluminum to gall together, so I’ll put some grease or some anti-sieze on it first.

I think if I warm up that bottom bracket with the propane torch it will give me enough clearance that these things will slip in with a mallet tap.
I put my adapters in the freezer and then use wooden skewers to align it while I press it in place. Grease too of course

Haven't done one in awhile but always worked well
 

Ulu

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I put my adapters in the freezer and then use wooden skewers to align it while I press it in place. Grease too of course

Haven't done one in awhile but always worked well
I put one of them in last night, and when I went to do the second one I found it was frozen to the freezer. I had to defrost it, and by then it was too late to finish the BB. Fortunately, the garage refrigerator is tiny and just enough for beer and bait.

Here I am doing the first one, and I just used a threaded rod with nuts and washers, and press plates from my ball joint repair kit.

D7AB16CE-367F-4A37-A880-0BE53C1AFFEF.jpeg

I put a good chamfer on the IDs and ODs before I started, and made sure there were no burrs to hang me up.

I put one press plate and the adapter in the freezer, and I use the heat gun to warm up the frame because it was very cold in my garage. When I measured this assembly there was one thousandth of an inch clearance, on paper. Both at room temp of 65F.

In reality, these aluminum things are not that round after welding (even though it’s obvious they machined the bicycle before assembly to get it true.) So even with the measured clearance, it’s still a press fit, and it’s not gonna move in that frame.

Assuming that I leaned on those wrenches with 20 pounds of force, I’ve developed a press force of over 1 ton to drive them in. I gave everything a coat of fortified lithium grease first, in case I want to take this apart, but that will never happen!
 
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Have you tried putting your things inside a plastic bag before you pop them in the freezer?

I have yet to try it, because I don't have a fridge in my garage in Lublin or my warsztat. It is on my list, but way, way down there.... ;)
 

Ulu

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Have you tried putting your things inside a plastic bag before you pop them in the freezer?

I have yet to try it, because I don't have a fridge in my garage in Lublin or my warsztat. It is on my list, but way, way down there.... ;)
It didn’t occur to me, as I haven’t done a shrink-fit in a long time. When my wife was working as a kindergarten teacher, she kept this tiny refrigerator in her classroom. Although she shared it with the other teachers, they made her remove it because “it wasn’t fair that everyone couldn’t have a refrigerator too.”

Anybody with $99 could’ve had one. Teachers in California were making an average of $45,000 a year.

But it tends to get frosty, and when I stuck that adapter in there it literally sunk into the frost halfway.
 

Ulu

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Heating up the iron vise, press plate, and frame. That frame by itself is a big radiator so if you want it to stay warm for more than one minute, you gotta heat up some iron.
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The top press plate and adapter were kept in the freezer until it hit 5°F. And I dropped it into the hole and tapped it twice. I put on the cold steel pres plate and cranked it down.
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Here are the adapters, pressed in and screwed together. I could not use the skewer method, so I just made little index marks on the frame and adapters with an x-acto blade.
7683A62A-9C18-4C80-AD3A-3C53360BA26E.jpeg


My dad’s old torque wrench is almost as old as I am. He built a wooden box for it out of bits of my highchair. I only bring it out on special occasions.
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It was so nice that I rolled it out into the sun for a photograph.
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It needs the frame longer and the chain shorter.
 

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