Building a Suspension Fork Impact Tester for Science

I bought a real cheap air fork that shows some promise-for the Kent Trouvaille of course. In our quest to upgrade this bike with the cheapest most effective parts, we need to step up our testing a bit. This is the reason why I'm going through all this trouble to build an impact tester.
Sure, the tester is a guillotine combined with a kettlebell, but with a little tweaking it could deliver better results.
In the future, we can add other jigs to the smeasher to fit other mountain bike parts in, and quite possibly parts we make here. You'll also find out next month where I'll be keeping this thing...
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[@quincybuickerood3070]

You need something to guide the weight down. This will make it so the weight hits exactly in the same spot each time, not just a similar spot.

[@SethsBikeHacks]

yes, like the one Cane Creek has. Part of the reason I didn’t was lack of ability. I may need to work this out…

[@ghostly07]

good idea but you are probably never going to hit the same spot in the real world

[@YujiSsi]

@@SethsBikeHacks I don't know if it's possible, but I guess you could drill a hole to attach a bar through the weights; and create a guide hole trough out the wood.

[@christiannieman8144]

Or maby even just directly mount the steerer in the clamp

[@MatroniFitness]

You may be able to put some steel or wood across left to right so the force equally distributes up and down. I bet you’re getting some torsional deformity in addition which affects its future deformities

[@michellesharpe6159]

So, you've made a bike fork guillotine. Love it!

[@TheNinthPhotography]

Happy to see that I am not the only one reminded of this particular device …

[@Pufferfishmaster]

I was just about to comment this but then i saw your comment

[@Herran42]

I saw the diagram and instantly thought guillotine

[@billydoesntexist5061]

@@Pufferfishmaster same!!

[@frl_drifts_official]

Pretty much.

[@nilz6432]

To actually use this as a tester, it needs to be significantly stiffer than the object you are testing. The Wooden platform that you mounted your clamps to will flex and dissipate a lot of the energy, allowing the Forks to experience less Load. Also the Weight needs to hit at the same place every Time, and the Forks sould be stopped from rotating. I could continue with this, but as far as fun and entertainment is concerned, the smeasher works perfect.

[@ThatVoxelBlock]

he might be getting close to patent information if he uses steel

[@falsemcnuggethope]

Maybe he should start testing wooden forks

[@ThatVoxelBlock]

@@falsemcnuggethope like a mediaeval mountain bike forks made with brass accents

[@nilz6432]

@@ThatVoxelBlock Yes, but you would still need a pretty decent Steel beam as a base to act as a counterweight (maybe 200-400 pounds?) or the whole things needs to be bolted to the concreet floor.

[@jamesroscoe7555]

Yep, the cost (and effort) to build this to properly test forks would easily exceed the cost of just buying a good high end fork, but the entertainment value as it is, is priceless! That sticker was hilarrious!

[@yakwabbit]

As an engineer, I appreciate the the term; 'moment' of truth. Perhaps that should have been the name for this device?

[@daviddoornenbal44]

I used to have that exact same fork on my bike, but it broke after like 5 months of taking heavy flat drop hits from 2 meters and a few jumps.

[@muhammad2086]

How did it break?

[@acr_master5594]

what broke on it?

[@40bikes]

@@acr_master5594 bolany forks Pretty poular here in SEA, lowers usually blow out near the arch. Crown cracks.

[@daviddoornenbal44]

By my fork the steerer tube just snapped in 2

[@daviddoornenbal44]

@@muhammad2086 i dropped a 1m drop to flat and then it made a loud noise and when i came home i took my bike apart and it just broke in 2

[@eddmorrell90]

If you ever get tired of riding with Seth, you can smeash things with Seth! Great video 👍

[@mtbrwannabe5484]

I have been watching you from 10k subs. There is still nothing more exciting for me, than to see “Seth’s bike hacks” has posted a video. I had just started to ride a bike again for some fitness, I found your channel, was totally inspired to push myself harder and faster. Then spent a large amount of money on my new whip, you showed me I can fix it myself. Heartfelt thank you for your abundance of inspiration you share all over the world, every time you post a video. Carry my love and strength with you at all times ❤️🤘.

[@Officialtheminimalmom27]

👆👆 congratulations I got a fantastic gift for you 🎀🎁 ..

[@curt13g]

Love the video. R&D Engineer here, if you put the fork at the top and tie a rope between the weight and axle then drop the weight, that would result in much higher consistancy in the experimental results and eliminate a lot of the variability in the impact. Could also throw in a strain gauge on the rope to get measuments of how much force is being applied and change the length of the axle/weight rope to alter the force beeing applied.

[@Officialtheminimalmom27]

👆👆 Thanks for watching and commenting. Let's talk 💬

[@bladesageproductions326]

Love the video maybe you could make a budget guide rail by rigging up some brake cable vertically on both sides of the weight and attaching the weight to it with small carabiners or eyelet bolts or attaching some short pipe to the weight to guide it I love your videos where you engineer and build stuff, you're quite good at it and it are relatable at the same time.

[@WestCoastMountainBiker]

I think the weight should have a flat bottom. That might already make a difference in the way the impact treats the fork as well as how the deflection will be if any.

[@andresgargut]

I was going to suggest the same

[@amechanicalengineer4088]

It's a good idea and an interesting route to take the channel! I will say, as a testing engineer, some of the design decisions were hard to sit with. I'm glad to hear there are some future revisions coming for the smasher

[@AntiDEDok]

just great idea, that definitely needs some upgrades. you totally got our respect because you mentioned problems with that version

[@Marvthegrate]

I particularly love the look on Oscar's face at 0:35 with captioning turned on.

[@tslaforest]

Thanks for the science lesson! Nice to see other people push the limits of parts. Maybe a frame stress test is next?

[@MTB_Rider_96]

Wow, Excellent job on this. I work in an ASTM/ISO professional test lab, and you did a great job on this.

[@Officialtheminimalmom27]

👆👆 congratulations I got a fantastic gift for you 🎀🎁 .

[@aydinatavash9854]

dont fall for the scam

[@SamSalty]

Seth goes above and beyond on everything and it is great. Customised sticker like what the hellllll!

[@whitmankwok1034]

Just finished our 3rd helmet impact test rig at KAV and we learn something new each time.

[@amiramz]

so i just remembered i noticed on several of your vids you were wearing a Winder Towing tshirt... just imagine how cool a colab vid with Matts off-rod recovery could be :) just putting it here... awesome vid! thanks bro

[@timmyreeves4546]

Netflix series I would watch it on repeat lol. This is one of the most entertaining KZbin channels I've seen thanks so much please keep them coming 🙏 👍

[@Officialtheminimalmom27]

Let's talk ^^,,

[@myprelove6818]

Hi seth, Big big love from philippines. i've been your fan for a month.

[@Littleweenaman]

I love this channel overconsumption is the best!!

[@benjaminjessop3429]

Seth! Please do a video on the camera gear you use and how you make your videos. What gear would you suggest for a beginner with a price range? What different types of products are available and what are they best used for?

[@cozmo4694]

The smasher could be improved in many ways, but i think a guide for the weight would benefit it the most. You should be able to add one with thick linear rods and bearings, linear rails (you can find big ones used from cnc machines for cheap) or v slot wheels but then you would have to build the frame from v slot extrusion

[@gustavobaquedano6992]

I hope you never stop making videos you’re awesome

[@MTBNewMexico]

I’ve been waiting for this video :) I was hoping for it

[@Nitrodozer]

It's crazy to think I've been watching you for about six years now!

[@WeekendPirate]

The mad bike scientist is at it again!

[@jonahtillman9499]

I have an XCR 32 in my mtb and it still hasn’t been upgraded because it doesn’t need to be upgraded. I’ve replaced my bars, seat, tires, brakes, and cranks, but man, the suntour forks and freakin indestructible. They’re a bit heavy, but the cheaper we can get people into mtb the better!🤘🤘

[@carlwilliams3488]

The XCR is loads better than that XCM, XCR has an alloy steerer, air spring, rebound damping and alloy stanchions. It's the first half decent fork in the Suntour range. My wife has one on her Cube Access, it isn't much different to the Raidon on my sons Voodoo Bizango really, but I haven't torn either down to compare them so I would think the damper in the Raidon wil be better.

[@f--lg1hu]

I can't wait to see what is to come in the future.

[@joshallen1846]

How many squares of toilet paper do you use to clean your Tallahassee?

[@bmxbandido473]

You’re a genius Seth!

[@Officialtheminimalmom27]

👆👆 Thanks for watching and commenting. Let's talk 💬

[@mtbville]

Awesome video Seth 🤩🤟🔥

[@RCandSR]

So creative and entertaining!😂

[@Officialtheminimalmom27]

Thanks for 👆🏻👆🏻👆🏻 watching and commenting give me a message I have a fantastic gift for you

[@knordberg]

I love the way Seth says "smash". LOL

[@B0BBY073]

Hi Seth, just wanted to let you know. In the Philippines, there are a lot of BOLANY Fork users because of its price. And one of my friends uses it on his MTB. It is great way for me to share this video with him. I can't wait to see this fork in action on the trails. Thanks for this one. Great vids btw.

[@MrHawkis]

I love your videos, they’re always nicely done. It’s really funny, this video made me think, “Ok, but do you really need to build this thing?”.

[@Officialtheminimalmom27]

Thanks for 👆🏻👆🏻👆🏻 watching and commenting give me a message I have a fantastic gift for you

[@mdturbo764]

"Honey! Look what I built! Its a guillotine but with a weight instead of a blade so its only 2/3 as dangerous and so it will be perfect for our kid! Their gonna love it! - Seth's final words before death by wife using his own creation "The Smeashotine"

[@sebastiana.345]

Hi seth 1: love the content. 2: you haven't made a tips/tricks video in a while and maybe im dumb but I can't find a video for the essentials for a solo ride, as someone who started riding solo once I got to college I forgot some important things on my first ride and I think it would be a cool video to make.

[@62swampboy62]

No free advice here LOL. Loved the vid.

[@thisisabsolutelystup]

Congratulations on the workers comp machine

[@laneoler6506]

So sick love the vids so much

[@Anderson_999]

Now we just need a Berm Peak express video of you smashing random stuff in the smeasher

[@fisherhayes6828]

I smell a series cooking up!!

[@zacht017]

Hey seth. Something you could try to fix your issue with the box limiting the amount of deflection the forks have is you could add a second rope and pulley and pull on a angle with the weight tentioning the rope only a few inches before it hits the ground. That way the sky is the limit for how far the fork can bent. Hope that is helpful. 🤙

[@sheldonh200981]

That thing is awesome

[@neotim5]

Thank you for your content, made me go out and ride my dusty thing again

[@Officialtheminimalmom27]

👆👆 Thanks for watching and commenting. Let's talk 💬

[@Porter3]

Love on of those air forx love the videos

[@carlwilliams3488]

I've used Bolany cassettes a number of times when doing budget 1x upgrades. They are excellent VFM and have all worked well so far. Better quality that the Sunrace I purchased.

[@evan24pen]

A quick and dirty way to guide the weight down might be a set of long, heavy duty drawer slides mounted on both sides with a middle frame to hold the weight and keep them square as they descend. Excited to see the modifications!

[@derrickquintal]

Another absolute Smeasher of a video Seth!

[@Officialtheminimalmom27]

👆👆 congratulations I got a fantastic gift for you 🎀🎁,,

[@RicardoPetrazzi]

This was very cool. 😎👍

[@Officialtheminimalmom27]

👆👆 congratulations I got a fantastic gift for you 🎀🎁

[@jonahkrynski8001]

Woah! Return of the SMEEEEAAAASH?

[@dibster7731]

i love these vids so much

[@rabonour]

This is vintage Seth's Bike Hacks level of sketchiness... love it.

[@Officialtheminimalmom27]

👆👆 congratulations I got a fantastic gift for you 🎀🎁

[@rupedog]

Nearly 2.5m subs.... wowzers 💪👏👏

[@benjaminblakemore9704]

DEAR BIRM PEAK, HERE IN NEW ZEALAND, UNFORTUNATELY IT HAS BEEN A CRAP SKI SEASON AND MT RUAPEHU IS IN RECEIVERSHIP. THIS WOULD BE THE MOST EPIC MOUNTAIN BIKE FACILITY BRO!! CHAIR LIFTS ETC.... I THOUGHT OF BIRM PEAK YOU COULD HELP MATE!! DONT LET THIS DIE, KINDEST REGARDS BEN FROM NZ 👌😎😜

[@slow_RIDAAA]

Yes thank you I wanted to get this fork

[@aervinreyaguillon2616]

I've seen many bolany forks here in philippine and they sell it for only 2,000php around 35usd. I seen also many broken arch of that fork even though the trails is for xc with minor jumps.

[@elgiedeleon4393]

Keep on creating interesting, meaningful, informative, straightforward, helpful and honest contents! Did I just become a bit too redundant? Anyways! Great job!

[@elrictdb]

I really enjoyed this video, like you took pains to stress, version 1 has some flaws but you still made an awesome tool to learn something to pass on to new bike owners and your viewers. I'm dying to see the next one already because "upgrading" to a cheap air fork from stock Suntour coil is something alot of budget conscious people are definitely going to think about. A home built rig is never going to be flaw free (perhaps bolt some steel on to help reduce some flex if it's very excessive), but I do believe that the data will be useful in helping come to conclusions about fork suitability....like I was amazed that the zoom hydraulic brakes you used recently actually stopped a bike /shock'n'awe!

[@Officialtheminimalmom27]

👆👆 Thanks for watching and commenting. Let's talk 💬

[@oleksiykolesnykov339]

I have a weird nostalgia of sorts for “smeash”, amazing

[@RTurnquist]

Love your videos

[@heathb4319]

I learned something today and i enjoyed the video. I learned how not to make a smasher :) Love you brother, keep it up.

[@Officialtheminimalmom27]

Let's talk ^^...

[@mOkz312]

“sounds sketchy but stick with me” Sketchy is why we stick with you Seth

[@aarongreen9014]

Seth is now the dignified Whistlin Diesel of bikes.

[@JH-tc3yu]

Comparing anyone to that jackass is more of an insult than a compliment

[@PePratiMTBRoma]

Awesome Bro:)

[@samueldeter9735]

5:01 man it was probably just me, but boy was I eyeing that closed garage door on your initial test

[@hardwoodswisconsin4871]

Idea for your smasher, run the kettle-ball through large pvc or similar pipe to guide the decent. Drill holes in the pipe to view the weight drop. Good luck 👍

[@brycebonilla4288]

Hey Seth, you should try tapping screws into the metal pipe that holds the fork that screws into the steerer tube, so that the fork does not deflect or come loose

[@Officialtheminimalmom27]

Let's talk ^^

[@DonaldEdney]

Seth is becoming the project farm of biking

[@bmxscape]

that sounds amazing

[@wasifzihan4662]

As a to be mechanical engineer and a diy crafter I praise the effort seth. But it would be thetter if the weight had a angled point which would hit the fork, also, you can build a guide for the weight to come down precise everytime with the sideposts as guide rails.. And the steer tube clamping vice would fare better if they were mounted to a hard surface, The wood would create dents and lose energy

[@LiveLaughJordan-oi6tg]

Lmao SMEASH! Man I love your videos

[@Officialtheminimalmom27]

Thanks for 👆🏻👆🏻👆🏻 watching and commenting give me a message I have a fantastic gift for you

[@sotoboxios]

THE SMEASH STICKERS ARE BACK !!!

[@Officialtheminimalmom27]

👆👆 congratulations I got a surprise package for you 🎀🎁

[@christianhb3314]

Thanks for looking out with this sweet sweet *Chefs Kiss* content Seth. Con mucho mucho amorrrrrrrr

[@Officialtheminimalmom27]

👆👆 Thanks for watching and commenting. Let's talk 💬

[@charlesc3664]

It would be cool to test out carbon bars on their smash strength, I’d imagine only thing to change is the clap method.

[@oldetymebiker2405]

I was like the Scottish dude from family guy. "Ah Seth, yer doin et wrung, why ar ya doin et like thaaaat" I'm glad you put the different ending in.

[@Porter3]

Love the videos

[@mtbwithfinn]

Really cool!!!

[@emoneydev8684]

Nice, I need one for fun

[@Jack-cy8qg]

Hi Seth! My name is Jack and I’m from Nova Scotia. I really love your videos and my Dad and I decided to build a bike trail in our back yard! Do you have any ideas on what we should build for new bikers?

[@Stickman550]

My favorite thing about this video was the amount of times seth said "smash"

[@Officialtheminimalmom27]

👆👆 congratulations I got a fantastic gift for you 🎀🎁 ..

[@James_carved_a_thing]

Hey love your work

[@NonLegitNation2]

A friend of mine just got this exact fork for his e-bike 2 weeks ago to replace the heavy stock coil fork.

[@originaljws]

seems like you need a more "standard" headset setup to keep the steer tube from sliding/banging around in the clamps. The 2 clamp setup you have seems unnecessary, you could use a pipe (or cut off head tube) sized to fit the top of the steer tube with a bushing instead of a bearing and a normal topcap (perhaps with an expanding plug instead of a fangled star nut). At the bottom you could use a similar setup (bottom of head tube, bushing) or a simpler "yoke"/cradle to act as the fulcrum. +1 to guiding the falling weight...maybe garage door tracks or sliding closet tracks? Something to keep the force in the Z alignment.

[@antonioZaRasFiNaLbOsS]

You're actually lefty! Wow i didn't know that. That's awesome!

[@mikemarion2154]

I have the BOLANY 27.5 with remote lockout on my ebike. For my purposes it's good so far. But the dust seals are super hard and scratch the stanchions. Good too see it held up to the insane abuse that Seth could throw at it.

[@Officialtheminimalmom27]

👆👆 congratulations I got a fantastic gift for you 🎀🎁,,

[@tobins6800]

I'd say use C channel you can get from the big box store. Also, a weight platform that has a set weight already, for instance 5 lbs, that is easier to add weight to and a way to secure it.

[@keithcampbell5914]

“Bodily harrm” for when the bodge really gets you.

[@caledfwlch]

Return of the “SMEash”

[@chrisgenovese8188]

I was wondering what you would name it. Was not disappointed.

[@owen_som]

any trips coming up soon? More riding videos would be awesome

[@outoffocus875]

those stickers really give it a personality

[@michaeltorres6109]

That fork is popular here in the Philippines. Low quality specially the stanchion. Easy to break and also arch. Can't wait for another test. Be safe on using it on your bike. Keep safe

[@ertai222]

The dogs like "what're you doing Dad?"

[@MartinTeerly]

I'd like to see how much crank can take 👌🏻

[@code3xiv]

No need guide rail. Just a plank with hinges on the other side that rest on top of the fork. The pivoted hinging plank only go one direction which is down/no side slant. Thats good enuf.

[@gerp9p788]

could you maybe show us your whole garage and stuff? would love that

[@SkiRidesMTB]

They've done a bunch of shop tours on the channel.

[@michellesharpe6159]

He seems to do one almost every year, and they get better every time.

[@SkiRidesMTB]

@@michellesharpe6159 They also moved houses twice and kept adding to this shop. It doesn't really seem like they've added much to the shop in the last year.

[@kw6919]

Perhaps replace the Stem Tube holding pipe with a PVC Pipe that can actually flex to hold the stem lightly to keep it from rotational deflection. Just a thought.

[@MyChannel-eo9tw]

thinking can you weld a metal piece to the bottom of the weight that is the horizontal length of the box to smeash and not twist the fork

[@natr8301]

i had a very similar fork to the baloney. during one quite bad nose case the valve where you pump the air in blew off couldn't hold air once re attached.

[@Officialtheminimalmom27]

Thanks for 👆🏻👆🏻👆🏻 watching and commenting give me a message I have a fantastic gift for you

[@mdrochford]

All this talk of guide rails, but I want to see more of Seth’s Revel Rail. NBD and then radio silence was quite the tease.

[@Officialtheminimalmom27]

👆👆 congratulations I got a fantastic gift for you 🎀🎁