Acid. Reborn (finished)

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Suspension linkage done from good old Swedish “bondjärn” (nicknamed ‘peasant steel’, formally C9D (SS 1312) steel.
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Tested it today. As requested by @OddJob, here is a video it in motion

Overview video
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Closeup video
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Turns out @metalchewy was perfectly right, the springs are too weak. Probably need about double the force. Either parallel springs or just beefier ones.

Test was successful though, as I’m quite happy with the suspension travel range and its progressiveness; gradually reduced mechanical advantage for the linkage through its travel, so it doesn’t bottom out harshly but very gradually
NICE! Now you have planted a seed, now I’m thinking about rear suspension as I wait on my rear wheel build. Think I’m just thinking though. I’m impressed.
 
I would like to make a tank of some kind, possibly with faux air intakes.

Any suggestions on design?
 
I would like to make a tank of some kind, possibly with faux air intakes.

Any suggestions on design?
One I did with a similar frame.
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Today I made a front brake caliper mount.

First, attachment to dropout
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…to fix the caliper mounting plate.
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With the bike turned upside down, I found the reason for the wheel sitting so crooked in the fork.
-I can’t grasp that I overlooked this for so long.
The fork’s spacing is wider than my wheel’s 100mm.

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So, ad modum @GeePig, I cut off a dropout.
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Fitted the extra dropout to one side…
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And voila, the wheel is straight and secure, fork legs somewhat parallel.
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Finally done!
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In motion
 
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As work continues, the progress bar goes backwards.

I started experimenting with a high pivot idler pulley system. We'll see if I keep it or scrap it.
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https://www.bikeradar.com/advice/buyers-guides/what-is-a-high-pivot-mountain-bike/High-pivot designs originally rose to prominence on downhill bikes in the early-2000s. The high pivot helps the rear wheel suck up everything it hits.
The reason is that a high-pivot system has a more rearward axle path as the suspension compresses, allowing the rear wheel to take a smoother path over obstacles. This translates into a smoother, grip-abundant and planted feel on descents and climbs. That is why high-pivot suspension systems feel supple and are able to soak up rough terrain with greater precision and ease.
As a high pivot’s rear suspension compresses and the wheel moves up and rearward along its arcing path, the bike’s effective chainstay length (the distance between the centre of the bottom bracket and centre of the rear wheel’s axle) grows. This, in turn, results in both upper and lower chainline growth – the lengthening of the distance between the centre of the rear wheel axle and the bottom bracket.
Lower growth is compensated by the rear derailleur cage moving forward when the suspension is compressed.
Upper chainline growth, on the other hand, causes pedal kickback. Because the cassette and chainring move away from each other when the rear wheel is moving backwards, the cranks are ‘pulled’ back as the suspension compresses.
The idler pulley is the high-pivot solution to pedal kickback. If a traditional drivetrain setup were used, pedal kickback and pedal bob, where the bike’s suspension dips in and out of its travel as a rider pedals, would be a significant problem on high-pivot bikes. The idler pulley allows for pedal kickback to be virtually eliminated.

So I could say that a high-pivot suspension offers plusher-feeling suspension with better grip on rough terrain. Its downsides being pedal kickback and pedal bob. But by routing the chain over an idler pulley, near the high-pivot, chain growth and pedal kickback will be significantly reduced, and possibly offering the best of both worlds, blah blah blah…

It's like side pipes and injectors on a Charger
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Prototype for a rear brake caliper mounting bracket
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Before I test fitted the projectors, I got a pair of OEM Kia Optima LED DRLs on an auction, dirt cheap.

They look nice. Not sure how I’d mount them though as they’re quite large. Maybe I’ll saw of the innermost pair from both sides and combine them to a quad light
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