Anything Goes! FM71 2019 chopper

#1
I'm in. Been a while since I played along and I need to purge my shop of extra parts. I've always favored the scratch builds and can't seem to get enough of the chopper style so here goes. Going to enter a scratch built chopper for my 2019 build. I'm attempting to keep the design simple with a rigid frame and forks, 10" OldMiniBikes chrome wheel kit with drum brake, and a predator 212 for power. Pics attached of my rough sketch along with my parts cart and 7/8 tubing. Machinists handbook from 1956 on my bender. Happy building, thanks for having me and thank you Dave for the moderation.
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#4
Received my wheel/tire package along with a couple other necessities from the OldMiniBikes-Warehouse yesterday. Really excited to get the main tubing rails mocked up to the proportions I'm striving for. I went with a Rupp Trials tire for the rear because it makes more sense for the terrain this will most likely be driven on. Thanks OldMiniBikes-Warehouse for the timely shipment, it's just in time for me to get busy/started this weekend. IMG_1429.JPG
 
#5
Day 1 of my build. Laid out the frame pieces, bent and tacked up on a jig/work station. Proportions are not coming out as my original drawing showed but like all things, I'm just going to roll with it and let the build take on its own personality. I had to raise up the neck area in order to clear the predator engine and tank and it will definitely be a one of a kind bike when all is finished. IMG_1448.JPG IMG_1454.JPG IMG_1455.JPG IMG_1456.JPG IMG_1457.JPG
 

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#7
Thanks Chipper, they make quick work of setting up and can be easily moved when you're mocking up designs.

I Put the rear wheel halves together and mocked it up in the frame. Still need to adjust the jackshaft setup and make the mounts for it and the rear axle. Will be adding some cross bracing/gusset tube above the tank area which will give strengthening and add some visual appeal by simulating a traditional gas tank. Neck tube will be cut next and welded in place along with some gussets to lower frame rail. Frame height is about 23", wheel base comes out about 48" with a seat height of 16-17" so it's not exactly a mini but should make a comfortable ride. Still considering a small banana style seat with moderate sissy bar setup IMG_1460.JPG .
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#8
Placed a couple braces between the upper and lower rails and started to weld in the neck area but need to come back to this later after I warm up a little. Most likely will require some body filler if I can't blend the weld passes in better. Will post more updates towards the end of the week, happy building to all!
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#10
Looks like everyone is making good progress so thought I would post a quick update. I put a jackshaft together and massaged the drum brake lever a little in order to get it in alignment with the cable and frame rail. Also played around a little with some mockups in order to make sure my proportions were still to my liking. My next step is one I've been dreading and that is to make the front forks and handle bar. Debating on whether I want to incorporate some type of springer (which I have attempted before and not had good results) or keep it simple. Also, anyone know why I can't get a 5/8 axle shaft into these wheel bearings? They seem a little tight and the calipers proved it wont go. Wondering if I should shave a little on the lathe or change these bearings which I doubt I can get out without a press. (they wouldn't budge with a little persuasion worrying I would distort these wheel halves.). IMG_1486.JPG IMG_1487.JPG IMG_1488.JPG IMG_1490.JPG
 
#14
I made a little more progress on the front end area. As I anticipated, this has been the most challenging for me with the hardest part being maintaining symmetry while setting and tack welding the sections in. With everything in its proper place and measured for symmetry, my next step will be to finish weld up everything and start thinking about where the smaller brackets and final parts need to be on the main frame. I tried turning the photos to the correct orientation but they continue to load the other way. Current progress below. IMG_1508.JPG IMG_1511.JPG IMG_1514.JPG IMG_1517.JPG IMG_1518.JPG
 
#15
I made a little more progress on the front end area. As I anticipated, this has been the most challenging for me with the hardest part being maintaining symmetry while setting and tack welding the sections in. With everything in its proper place and measured for symmetry, my next step will be to finish weld up everything and start thinking about where the smaller brackets and final parts need to be on the main frame. I tried turning the photos to the correct orientation but they continue to load the other way. Current progress below. View attachment 241123 View attachment 241124 View attachment 241125 View attachment 241126 View attachment 241127
Wow. Really nice.
 
#17
Sorry haven't posted in about a month -sort of lost some of my mojo but after last week's snow storm, I'm more motivated this week with Spring in the air and 50 to 60 degree temps. Happy Easter! and below are some pics of setting up the rear chains and making some axle mounts. Still haven't done much with the front end but hoping to get the backend taken care of today and start making the seat hoop and sissy bar. IMG_1554.JPG IMG_1557.JPG IMG_1558.JPG IMG_1559.JPG
 
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