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Hello all,
My name is Kyle. I live in Oregon, and I'm building a bike.
I've been riding bikes all my life and have raced mountain bikes for the last 5 years or so. I've always wanted a bike with a motor and not a electric or 2 stroke. I'm no stranger to custom built stuff. I "resto-modded" a '71 c-10, lowered, c notched, shaved stuff,etc. I current have a jeep xj with lots of subtle things done.
I sourced a frame and a motor.
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I don't know what the frame is. The paint was stripped and no badges.
The price for both- free!
 
I'll call it a Schwinn. The Briggs motor is a 5hp off a really old rota tiller. It's sat for a while but some brake clean down its throat fired her up right away. I'm going to change the carb and build a exhaust pipe, of course.
The frame is small. So I had to cut the downtube.
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I played the front of the bb with 1/8" wall to cover the old downtube hole and to give a thicker surface to weld to. I notched a piece of 1.25" tube horizontal out about 12" then used the rest of the old down tube to connect it.
I'm not stoked on the kink in the old down tube, I'll probably change it.
Any way, today I cut the old drop outs off and widened the rear to fit a 135mm shimano hub with a cromo bolt on axle.
I cut out some 3/16" drop outs and slotted them
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I roughly tacked them In place to get a visual.
Stuck the fork I want to use in there for more of a visual
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It's a rockshox 140mm travel 27.5" fork off my trance. Obviously I have to change the head tube for it to fit. It's a tapered steer tube. That's where I'm at now. Just mocking things up.
 
Looks great really like the look of the frame modifications. Should be a fun bike to ride .


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Thank you. I'll be ordering jackshaft parts soon. What gearing should I start with? I'd like to have a solid 35mph. There are some hills around here
 
Looks like it could be cool, good luck on the build.
If you have a serial number from the frame, you might get an I.D. if you want it.

Welcome to the site. Whereabouts in Oregon? I use to live in Corvallis, and RRB member @RustyGold is out there. Probably a couple others as well.
 
Thank you. I am in bend. It would be nice to pick someone's brain. I'm going to change up a lot of things. Probably be completely cutting off the seat and chain stays and starting over. Put another BB between the rear wheel and the seat post. I need to get a wheel set and head tube for the fork. I'll lower the fork to about 80mm travel.
 
Well, you're definitely in the right spot for brain picking.
Unfortunately, I won't be much help. Only built a motorized bike with those Chinese kits, but watching this will be educational.
 
I'm still on it. Though I'm kinda at a stand still right now. I need a wheel set and a headset to get the frame geo finished. Doing it on a budget just makes it take longer
 
I found a wheel set I'm going to use. 26" mtb stuff is a little harder to fine now days. I'm going with a 27.5" front and a 26" rear. Both dual wall rims. They are both tubeless compatible so I can run the tires tubeless.
I have a good friend at Hope tech right here in bend. He hooked me up with a head set. Next step is the steel shop tomorrow.
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I flipped the drop outs and trimmed them. Just had to get a profile shot. The head angle will be similar to that.
Looks cool tho, I'm excited
 
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I got some 1.25"x .188" wall tube from the steel shop. I don't have a bender but I have access to a massive press. I used plates that have centering channels. So I slowly finessed a curve in to the tube. I would tap the tube with a hammer to relax the steel. It took about 30 presses to get this curve.
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I cut out the old downtube, notched the new tube and set it in place.
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I had to order a head tube off the internet from nova frames. It should be here next week
 
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Serial # looks like I or T 6855242
Couldn't find it in the schwinn database, no idea what it is.

Overall stance is looking good.
 
Update!
I had to backtrack with the head set. The head tube I got was 44mm straight through. Which is fine for tapered steer tube. But the headset I bought was much bigger. I swapped it's out for a 44mm headset. I didn't completely cut the old head tube off the frame. I cut it down the sides and opened it up.
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Like that.
It made lining up the new tube easier and made more weld surface to the tube. I drilled a few holes for extra spot welds.
After I welded the tube on I cut it to length. 5". I'll have to trim it more cause the steer tube isn't long enough. There is plenty tube left to cut above the top tube.
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Some grinding. Then pressed the headset in.
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The final stance should be similar to this.
Wheel base is around 47"
 

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