WBO Project Oldboy

Starnger

Pro Member
Aug 4, 2016
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Poznan, Poland
Hi everyone!
I have made a post, asking if i should take part this year with a bike i have already had, and people seemed to be quite okay with it, so here it is!

Let me introduce you to the bike. Here is the frame, 90's made stingray copy purchased from USA.


The plan is to build newschool/oldschool mixed BMX with some influence taken from two motorcycles from Kustom Konwent in Wroclaw last year.
Here are GT mags from 2001 Dyno Air i parted for that build


Here are the motorbikes that i want to refer to visually.



Today i have started to actually working on it by welding the braking bosses to the fork.
Starting with cleaning a newer style BMX forks up.
IMG_4514.JPG

Then making this simple device to hold bosses perfectly in needed distance.
IMG_4516.JPG

Next step is setting all up on a welding table for max precision :)
IMG_4517.JPG

And here we go, the fork is ready to accommodate v-brakes!
IMG_4519.JPG

Next step is to figure out how to attach so called gyro, the system to prevent braking cable to intertwine when turning the bars around.
 

Starnger

Pro Member
Aug 4, 2016
747
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Poznan, Poland
here ya go bro...
View attachment 109184 View attachment 109186
They're a couple different brands but pretty much the same line up...

Carl.
The issue is that i have two complete setups like that, but none of them would actually sit in my frame. The bike has 32.5mm head tube 1" , i am going to use modified 1-1/8" headset with it. The head cup of gyro is supposed to be pressed by the headset cup, but actually is too loose, since the frame head tube is more narrow. I might try to cut the headset cup deeper, to have more pressing surface, or weld the plate onto the frame, or possibly use threaded solutions like modern BMX bikes have. Three options to choose from, and a bit more research to be done for that, to make sure which is the best :)
Thank you for support! :)
 
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Apr 28, 2019
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The issue is that i have two complete setups like that, but none of them would actually sit in my frame. The bike has 32.5mm head tube 1" , i am going to use modified 1-1/8" headset with it. The head cup of gyro is supposed to be pressed by the headset cup, but actually is too loose, since the frame head tube is more narrow. I might try to cut the headset cup deeper, to have more pressing surface, or weld the plate onto the frame, or possibly use threaded solutions like modern BMX bikes have. Three options to choose from, and a bit more research to be done for that, to make sure which is the best :)
Thank you for support! :)
The headset cup is too loose on the frame?

If you want I have more of the adapters that my friend made for the K-Rat:

You can use them to adapt a 1" headtube for a 1 1/8" headset.
 
Sep 14, 2013
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Bradley Illinoiz
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I wonder if you can create, find or modify a couple thin washers to pinch the headcup with? Or even one piece to weld into the head cup, effectively creating a 1" headcup...

Carl.
 

Starnger

Pro Member
Aug 4, 2016
747
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Poznan, Poland
The headset cup is too loose on the frame?

If you want I have more of the adapters that my friend made for the K-Rat:

You can use them to adapt a 1" headtube for a 1 1/8" headset.
Thanks for the offer, but what i have here is not our normal 1" so common in Europe, but old USA 1", usual for on 80's BMX bikes. I also would be happy to practice my lathe skills in case making an adapter would be the best option. But by now i am looking into using modern BMX threaded gyro mounts.

I wonder if you can create, find or modify a couple thin washers to pinch the headcup with? Or even one piece to weld into the head cup, effectively creating a 1" headcup...

Carl.
I am quite sure it is possible, but just taking a bit of material off the existing 34mm headset cup seems to be an easier solution.
 
Sep 14, 2013
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Bradley Illinoiz
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Ah. I didn't catch that the headset cup was big. I was thinking it was smaller.

You have one of those rubber bits that hold sandpaper cylinders? You may be able to chuck that cup up and spin it against a file. I'm always looking for a down and dirty way to do things with hand tools on hand...

Carl.
 
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Starnger

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Aug 4, 2016
747
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Poznan, Poland
Ah. I didn't catch that the headset cup was big. I was thinking it was smaller.

You have one of those rubber bits that hold sandpaper cylinders? You may be able to chuck that cup up and spin it against a file. I'm always looking for a down and dirty way to do things with hand tools on hand...

Carl.
This is already solved, since i have an access to a lathe at school. But still somehow the cup does not press the plate enough, while functioning perfectly in every other way. That's why i decided for an alternative solution.
Filing cups attached on a drill is also a method i used a couple of times though! And it is less violent on the tooling, since they are often very hard steel, and brake simpler lathe blades :) But however also less precised and less controllable.
 
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Starnger

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So, finally had time to work on the bike.
I managed to fit the gyro and the wheels quite well. However, i found out that the front wheel tire is too wide, and rubs against the brake bosses. Also, apparently the bosses i used are not same as the ones i need, so i would have to change the bosses for the wider ones to work with u-brakes from my Dyno. Or switch to v brakes, what i don't really want to do. Caliper brakes are not an option since they most probably won't clear the wide tires.
I guess i am going to switch to rear brake only now, and would have to modify the frame again.
IMG_4759.JPG

IMG_4760.JPG

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Some goodies like NOS seatpost clamp and headset cover add up to the build and more cool oldschool items are to come! Pretzel bars also look awesome here.

IMG_4757.JPG

IMG_4758.JPG


I like the looks of the bike a lot so far, now i need to fix the functionality and to try to manage with painting before the deadline.
 

Starnger

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Aug 4, 2016
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Poznan, Poland
Hello everyone!
Time for the build is running out, so i have decided i will not paint the bike for now and do it later, to be able to get the best quality i can without a need to hurry. I actually like the way the bike looks as is, even without any paint. I still need to modify the frame and fork again, adding the correct bosses. I found the source for them, but still had no time to go and buy them, and then to take the frame apart, weld them and put back together. Next week i am planning to do that, so i should be okay with the deadline.

In the mean time, couple more cool bits have arrived. Here is a nice (probably 1980s) checkered seat and a KMC golden chain. I expected the color to be more saturated on that one, but still looks good.
IMG_4789.jpg

Also, since the bike is going to be purple in future, i decided those valve caps would look cool on it! Ones of those things that sit in your parts stash for years waiting for THAT build :D
IMG_4790.jpg


Here is how the bike looks at the moment:
IMG_4791.jpg
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I also have learned, that "El Gordo" means "The Fat" in Spanish. That's what the original sticker i still have on the left side of the frame says. Kind of fits the build too :)
 

Starnger

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Aug 4, 2016
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Poznan, Poland
Those mags keep Killin me! I've wanted a set for about thirty years! Fat tires look great on them
I just got very lucky and found mint 2001 Dyno Air for sale at olx.pl, that is like local craigslist for like 100 bucks. Those things don't pop up here at all! I was just searching for a new set of mags for my trailer, and got this. Needless to say i was very happy, this is the only one like that i have ever seen in real. Now the frame and other bits are used for a custom built bmx for a friend of mine, so the bike got a nice new life. I am also glad it is not so old, so i haven't felt too bad parting it.
 

Starnger

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Aug 4, 2016
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Poznan, Poland
Time for some custom stuff.

I start with powder coated black 44t plain sprocket.
IMG_4796.jpg

Then i get some Oracal vinyl film, transfer foil, cutting mat and other tools.
IMG_4797.jpg

Then i let the plotter do the job for me, instead of sitting there for hours cutting little elements :D
IMG_4798.JPG

After that i use the transfer foil to transfer the cut pattern to the sprocket. It is important to degrease everything in the process for better adhesion and make sure no air bubbles come in.
IMG_4799.JPG


As you can see i did not manage to center the pattern perfectly, but i got pretty close. If i won't like the result i can always redo it later. Now time comes to clean the part up by removing unwanted elements from the sticker.
IMG_4800.jpg

That's how it looks after all the background material is removed:
IMG_4801.JPG


And that is the final result, after putting back the pieces that didn't catch with the transfer foil or did stick to it too much.
IMG_4802.jpg

Should match my seat well :)
 

Starnger

Pro Member
Aug 4, 2016
747
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28
Poznan, Poland
100$ is stelly pretty much for a set of 20" wheels :eek:

Purple? Why not leave it bare metal, it looks so cool right now :cool2:
Yes, 100 for the whole bike. 60 would be the price for mint Piston stem only, another 40 for those handlebars :) I also sold the frame set and leftovers like tires and seat, so that was quite a good deal with that one.
And talking about the color, you may be right. Probably it is just my imagination that is so occupied with how i have imagined the bike. But somehow i still think nice dark sparkly purple would fit all the black and gold parts well. When i put the black seat post and Piston stem on it, the frame would be only last part that is chromed, so why not darken it out.