Project "Firebolt"

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So, i've made some tooling to align the mid tubes today. The distance between the tubes on the back would be exactly 100mm now.
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Then i wanted to try to make some small notches in my mid tubes front, but my setup is too sketchy for that for now, i didn't manage to mount it well enough so the vibration doesn't let to unalignment.
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So i ended up just making those little notches by the grinder.
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Then i've test-fitted them once again, to mark the notches that would help the tubes to rest on the seat stays.
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While working on the bike, i've decided to throw some wheels in just for the size reference.
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While i obviously really like the looks of the vintage fork on it, the frame is designed for more offset, and there would obviously be a clearance issue even without a fender installed.
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If only i'd have a damaged Shockmaster fork, i would make it work perfectly here :) But i am too much in love with them to modify a perfectly fine one. Making a custom shockmaster inspired fork is long on my list, but would take more time then i can put into this now, so i leave it for later. I may end up still using it actually, just temporarily, before i can invest more time or money into the fork that would make this project shine.

Overall i am very satisfied with the bike proportions and it makes me happy to see it with the wheels. Though it is really still a bit far from finished, just the wheels make it look almost like it is ready to roll :D
 
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My friend Valery stopped by today and volunteered to help me with the bike!
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He is a professional welder, and only in comparison i can see how bad my welds actually are. Not that i ever thought they're perfect, but having a reference point it is even more obvious :D
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Together we started to put the mid tubes where they belong. Still some more welding to do there.
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You can use the shockmaster without damaging it. Make a set of extensions that will give the front axle the extra 2 inches forward it needs. You could also add some height and get the angle of the frame just right.
The horizontal support would be provided by bolting them to the existing drops and the vertical support would be supported by folded tabs made into the extensions which use the main fork legs for bracing. The tabs could be on both front and back sides of the fork legs or just the front, as that is where the force will be applied when there's weight on the fork. You wouldn't need extra braces.
The shape of the added dropouts could be in keeping with the lines of the bike.
I have limited skills on graphics, but here's the idea. The red line is where the tab would sit up against the fork. Of course the shape of the extension would be different than my crude depiction, but it would work.

IMG_6318.jpg
 
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You can use the shockmaster without damaging it. Make a set of extensions that will give the front axle the extra 2 inches forward it needs. You could also add some height and get the angle of the frame just right.
The horizontal support would be provided by bolting them to the existing drops and the vertical support would be supported by folded tabs made into the extensions which use the main fork legs for bracing. The tabs could be on both front and back sides of the fork legs or just the front, as that is where the force will be applied when there's weight on the fork. You wouldn't need extra braces.
The shape of the added dropouts could be in keeping with the lines of the bike.
I have limited skills on graphics, but here's the idea. The red line is where the tab would sit up against the fork. Of course the shape of the extension would be different than my crude depiction, but it would work.

View attachment 163150
I get this idea, and this is indeed a possibility. But i am afraid i just won't trust such an extension if it is not welded on with an electric bike. It is going to be a heavy and fast machine, so i need to make sure there would be no play possible anywhere.
But thanks for bringing this up, i would think about it and see if i can make it work somehow. Up until now i was also thinking on using some custom springs or extensions to spring mounting points to naturally lower the fork. But really even as is it seems a little too weak for an electric bike use for me. I guess only tests would really show if my concerns are rational or irrational.
 
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So, since welding the mid tubes is done, i've done a mock-up with the fork, and it actually looks better then i've expected!
I even managed to nicely mount it on the standard threads. The length and geomety of the fork allows me to run it both on threadless or threaded setup. I decided to keep it threaded for now, since i believe classic stem would look cool on that bike. Also cutting something off is always easier to do, then fixing it back in case i change my mind later :D
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I should keep in mind that since it is a suspended fork, the length would change with the weight on it.
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I guess i would just make it so the wheel axles are in line on the middle of the fork travel.
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Here is my first mock up for the fork drop out. A bit too low this way.
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Version number two is better. Not going to need a lot of offset on the dropouts, since i already have quite some on the legs. But i think it could still use a little twist.
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That's the way a-ha a-ha i like it!
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Though for now i am sticking to the version above, the shape kind of made me think of the spade symbol. Would look cool too considering it is a project 346 bike i am modifying. But i am aware that may be a bit too much going on. So i would try another one, more clearly in the spade shape tomorrow, and see if maybe i fall in love with it. If no - no big deal, i think i already have my favorite for now, so i can start to model it for the laser cut.
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I like the shape of those dropouts, especially considering it is a Project 346 frame. Maybe cut/weld 2 to each fork leg for a full spade shape? The rear could be drilled for fender braces or a disc brake mount…just thinking out loud….
 

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The midtubes are looking sweet

Maybe make the fork drops shaped like the 346 spade and mimic the other half of the spade with paint on the fork leg.

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Finally received some steel plates a couple of days ago!
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One big 6mm thick for the front dropouts and four 8mm thick pieces for the rear. The 8mm is so thick! But i believe it'd better be solid for the heavy electric bike.
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Then some fun with the laser comes, and i have a bunch of drop-outs and coaster brake tabs cut. Made a few extra in case i mess something up :) And if not, they would look cool on some other fork too. Maybe that old '47 Roadmaster fork?
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I've re-designed the shape a bit, so now it is smaller and a bit more accurate in my opinion.
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I've added a support bridge for the axle to rest on and some holes for the fenders. I've missed with the fender hole position for the rear a little, but we'll see if i want to re-make it once it is on the bike.
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The rear ones should be done soon too :)
 
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Mmmmmmniammm....

Will you be clipping the pointy bits off the top of the spades before welding them on, in case they melt during welding, or do you have another plan? I miss having welding kit around.
 
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Mmmmmmniammm....

Will you be clipping the pointy bits off the top of the spades before welding them on, in case they melt during welding, or do you have another plan? I miss having welding kit around.
I will sand them a bit on the surfaces and edges, but i am not planning to dull the peaks. If they melt - so be it :) The plate is quite thick though, so i suppose there is a chance it won't. I could also reduce the power closer to the tip, there would be enough surface contact for sure.
 

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