Bulldog

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This will be a Mini Velo type bike like I made last month, only this will be more rugged. Like a bulldog with it's short legs, this will have 20" wheels on a 24" frame. I've been using the frame for my exercise bike.
frame 24.JPG


I use a 26" fork to get clearance for the standard set of cranks. The wheels have heavy gauge spokes and are thick metal. I had the rear wheel made up this morning with a 7 speed cluster added at the bike shop. The tires are also heavy, 20 x 2.125 but thicker material than the usual. Bear claw pedals with a 48 tooth chain wheel. Low gear on the cluster will be super low. The handlebars and stems were cheap, so I bought 3 of the handlebars and 2 stems. They say GT, but we laughed about that at the bike shop.
parts raptor2.JPG

This bike will be made to take a lot of punishment.
 
The new derailleur was incredibly cheap, so cheap I was going to just make it a one speed on the 16 tooth cog. Then I remembered an old Suntour derailleur with worn pulleys in my junkpile and cleaned it up. It isn't perfect but it works. If I find the right pulleys for it then it will be permanent.
suntour.JPG

Now just the brakes and an inner tube. I'll test ride this this week.
progress 20 mar 21.JPG
 
The derailleurs aren't long enough to get the chain up on the lowest gear cog, the derailleur hits the 34 tooth cog. but on a 20" bike it really isn't needed. The cluster goes from 14 to 24 teeth, then jumps to 34. I had one of these on my 26" Diamondback some years ago so I checked the ratios. If I don't utilize the low gear, my 20" bike range is 40-70 gear inches. Low gear would be 29 gear inches. If it was a 26" wheel, the lowest gear would be 37 gear inches , so that's almost the same as my second gear. So I'm set for gearing. The Suntour shifts nice and smoothly with just a little chain noise.
cluster.JPG
 
I adjusted the derailleur and it'll get all the gears now. I was going to knock the rust off the forks when I noticed they have a slight backward bend. They were used, not NOS like everything else I got at the dump. I tried all my other forks, all too short for the headtube. This one had enough threads for the cone nut but no more. So I tried a trick I used awhile back, I attached the stem all the way down to hold the cone nut. Seems to work fine. And it's a NOS BMX fork, just right for this bike and almost the same color. The bear claws came off, they look good but catch shins too often.
bmx fork.JPG
 
I got the inner tube in and it's ready for a ride! Maybe tomorrow morning. There's only one rear brake because I'm waiting on cone wrenches to get the rear set up for a band brake. I'll have two brakes on the rear when it's finished.
bulldog mar 24 21.JPG

I was looking for a rack and remembered some wide flat bar I had. I'm planning on putting a 12" x12" rack on the front, just above the tire, taking advantage of the low center of gravity. I'll do some bending tomorrow. It'll be heavy duty in keeping with the bulldog theme.
Bulldog rack 1.JPG
 
The bike did very well on it's maiden voyage. It didn't get the lowest gear again but 2nd was low enough. It needs more braking too. It's just the right size to ride around the neighborhood.
ride 25 mar 21 a.JPG

The seat post has plenty of height adjustment.
seat height 25 mar 21.JPG

The hard part is the walk uphill back to the house. It's steeper than it looks.
hill 25 mar 21.JPG

It'll be complete when I get the front rack on it. And the extra brake.
 
Got some work done, my new cone wrench showed up and I installed the band brake, no long cable yet but that's all it needs. A lot of alignment work getting it done, different size washers and cone nuts. 2 brakes on the rear should be sufficient.
bandbrake 27.JPG

I bent some bar for the rack but 12 x 12 looked too big when I sized it up, so I'll look again tomorrow and see if it needs to be 8 by 8.
bend 27 mar.JPG
 
6 x 8 is the size it'll be. It looks normal at that size.
bending.JPG

I am thinking of using the brake bosses as a mount along with the brake hole in the fork. Then the front wheel will be able to be changed out without removing the rack braces.
 
The long band brake cable finally came in, and it was just long enough, no extra to cut off at the end. Now it has good brakes. I changed out the stem to one I had saved from an Earth Cruiser years ago.
I decided against the rack, it still didn't look right to me. So Bulldog is done.
2 apr 21 done - Copy.JPG

2 apr 21 - Copy.JPG
 
Now it's really done. I added a BMX style chrome fork and shined up the original blue paint as much as possible. Also a pic of the bike frame when I purchased it from the scrap yard. It was made to be a 24" ten speed road bike.
finished 17 Apr 21.JPG

While cleaning it I discovered that the rear rim is a real Araya, not like the other rims I have which are the fakes named Arava. It's like a Worksman rim with countersunk spoke holes.
17 apr 21 paint.JPG



bulldog frame salvage.JPG
 
With it's weight it didn't see much use, so I'm converting it to a 24" as it was made for. Instead of 10 speeds, it'll be a one speed coaster easy to ride with little maintenance needed. Simple. The biggest downside is the 24 x 1 3/8 tires that are available. It will get a splatter paint job and probably be ready to ride as soon as I get the wheels trued up at the shop. I laced up the rims in a 4 cross pattern to use all my stainless spokes meant for 26" wheels.
4 cross wheels.jpg


frame 15 Nov 21.jpg
 
I couldn't do any spraying of clearcoat today. The washed clothes are drying in the shop. But I finished the paint. I wanted to experiment with different thickness of paint, so this was more practice for my build off bike. I had two more colors to throw on but stopped while I was ahead.

splatter bulldog.jpg
 
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I bolted it together and see a geometry problem.
mockup bulldog1.jpg


The trail is wrong, too short, and the pedals come too close to the front wheel. I need to put more of a bend in the fork legs. That will level the frame along with making it steer correctly and look right.
 

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