🚲 How-To DIY Step By Step: Build Your Own Super Strong Torque Arms 💪

[@hightech-lowlife]

1. I'm seeing some comments from viewers coming to this video and not knowing what a torque arm is. I was going to include a small blurb in the beginning of the video, but if you're watching a video on how to make your own TA's then you probably already know what they are, but a lot of you apparently don't, so here's the part I would have included in the beginning: A torque arm is an additional piece of support metal added to a bicycle frame to more securely hold the axle of a powerful hub motor. It’s designed to help your bicycle’s dropouts (the part of the bike that holds onto the axles of the wheels) resist the torque of an electric hub motor. When you convert a standard pedal bicycle into an electric bicycle, the bicycle’s dropouts may not be designed to handle the torque produced by the electric hub motor. This is where a torque arm comes in. It grips the flat part of the motor axle and connects to the bicycle frame in a sturdy way to help resist that torque from forcing open the dropouts. Torque arms are particularly necessary when dealing with more powerful motors. From my personal experience smaller motors of 1000 watts or less are usually fine to run without (if your dropouts are steel), but once you start getting up to about 3000 watts, problems can occur, especially with front forks and weaker materials like aluminum. In these cases, a torque arm is required to resist the torque of the hub motor. 2. I'm also seeing the usual "that's not strong enough" when you speak about anything regarding torque arms. Most concerns are with the hose clamps: PF already did a test of tensile strength of a lot of hose clamps and almost all were over 1000lbs before failure (mish golds are over 5000), even at 1000, that's about 20x the weight of this entire bike. kzbin.info/www/bejne/oKWwgaRooaxgbrcsi=hdVrSRshWkTjnPjV&t=729 The QS205 (5KW Motor) puts out a max of 182NM of torque, which is 134ft-lbs of torque. The motor I am installing on this bike is 3KW, but will see peaks of 6KW, I'm confident that these hose clamps are more than strong enough for this application. If they are not, I will make a video on it, and also show my solution. This video is just showing one way to make them, you can add additional hose clamps, or even come up with stronger attachments (create your own steel clamp that is bolted, etc). Thanks for watching.

[@TheYUNGBALLA88]

This is the most sensible thing I’ve seen so far on e-bikes videos.

[@hightech-lowlife]

Thanks man!

[@sixfoursoul2538]

Thank you for this video! For all those who are clueless why this is important if you ride an E bike chances are sooner or later the torque from the axle spinning in the opposite direction is going to shred your dropouts especially if you have an aluminum bike, it finally happened to me after a year of riding, this is overlooked by most eat bike manufacturers but trust me it is a very real thing that can hurt you or even kill you if you do not have these on an E bike that has a 750 W motor and up....

[@hightech-lowlife]

Thanks man, I actually sit on both sides of the fence because I got a lot of flack for saying in a lot of instances you don't really need torque arms and I've built a lot of bikes that don't have them (without any issues). I take a nuanced stance that if your frame and power level requires them, then they should be used for protection, but if they don't, then you don't need to run them which is dependent upon a lot of individual factors. I feel I have gained the experience to know if and when I need to run them. A lot of people tend to think you need to use them for all applications, upon all ebikes, for all purposes, and in all scenarios, no matter what. This is something I don't believe. Of course it won't hurt your bike to install them even if you don't need them (although you do sacrifice some convenience, and it will cost you some money (or time, or both)). I don't have a problem with people running torque arms on their bikes even if I don't in some circumstances. I not only take responsibility for my choices, but I have the means to correct a problem if it comes to that. I do have a problem when strangers try to tell me how I should use the things that I own, that I bought with my own money.

[@sixfoursoul2538]

Well no matter what case you're in at least you're making good content I'm in a situation now where I never thought I would be in I've had my e-bike for over a year have over 1500 Mi on it's a Chinese e-bike and now I can't ride it because the axle keeps twisting out the only way to save this bike now is to find some type of welder or I hope these torque arm actually work whatever it is I have a challenge in front of me

[@hightech-lowlife]

@@sixfoursoul2538 Thanks man! Yeah, if you can get someone to weld on new plates for the dropouts you'll be back in business, that's what I would do. I have a welder so I can make such repairs. If you're inclined, you can get a stick welder for very cheap and it will do the job just fine, it just won't look pretty but it will be very strong. Or find a local welding place and tell them what you need, shouldn't cost too much to repair. 👍

[@HolgerBeetz]

Just a side note for those with a 3D printer: Some simple OpenSCAD script / CAD designing enables you to design a perfekt template matching your axle plus the angle related to the dropout of your frame. I even did a two part torque arm in OpenSCAD which was lasered from 6 mm stainless steel. There are a lot companies doing this for a relative low price compared to those mucho U$$$ torque arms from Grin.

[@hightech-lowlife]

These are great tips Holger, thank you. Yes once you have the 3D model you can get them cutout from a service like send-cut-send in whatever thickness steel you needed and it's not "too" expensive, especially if you need something precise and robust. 👍

[@E-BikingAdventures]

Hose clamps are relatively strong, but they are still just thin strips of metal. I understand the mechanical advantage, but I would feel better by putting 2. Doubling them up side by side.

[@hightech-lowlife]

You can put 3 if you want 😎

[@E-BikingAdventures]

@@hightech-lowlife . Wow! Three hose clamps. What a beast!

[@hightech-lowlife]

@@E-BikingAdventures You can also extend it as far as you want and also just weld directly to the frame if that's not strong enough 👍I will test on my new 6KW build and if the single hose clamps break, I'll be sure to let you guys know.

[@hightech-lowlife]

More research, PF already did a test of tensile strength of a lot of hose clamps and almost all were over 1000lbs before failure (mish golds are over 5000), even at 1000, that's about 20x the weight of the entire bike. kzbin.info/www/bejne/oKWwgaRooaxgbrcsi=hdVrSRshWkTjnPjV&t=729

[@yenerkayahan3737]

@@hightech-lowlife how does it hold up still going solid?

[@tacticooldennis]

Hose clamps don't exist with torque arms because of their quality to do this type of job, but simply due to their universal nature. You would be better off bending the steel to cradle the frame or finding a hole to bolt it to.

[@hightech-lowlife]

It's possible, this is the 2nd critique of "hose clamps not being strong enough", but unless you have data it's speculation. I will test these on my 6KW build, if they break I will let you guys know for sure. If they can handle it then I would confidently refute this speculation. I state that you can weld directly to the frame. The further from the pivot the less strong the hose clamps need to be due to leverage. You can also double and triple up the clamps if weary. Maybe for my next higher power build I will make a video on how to make even stronger torque arms. Most people are not running 6KW to their dropouts however, and these are more than enough for that.

[@hightech-lowlife]

More research, PF already did a test of tensile strength of a lot of hose clamps and almost all were over 1000lbs before failure (mish golds are over 5000), even at 1000, that's about 20x the weight of the entire bike. kzbin.info/www/bejne/oKWwgaRooaxgbrcsi=hdVrSRshWkTjnPjV&t=729

[@aayala1053]

​@@hightech-lowlifethat would be pretty intense. The 6 inch lever arm with a 1000lb breaking force, that set up should withstand 500 foot pounds of torque from either side, or maybe 1,000 ft lb of torque overall. Even at 6kw, you are at way less torque

[@markj6984]

best advice get rid of the hose clamps and buy heavy duty hose clamps. the screw on with a big bolt rather than a weak piece of aluminum. never really have to tighten them. u saved me alot of hassel i have two of those same cheap torque arms and one grin v4 but none of them fight correctly and everytime i ride the bike i worry. im doing this tomorrow lol

[@hightech-lowlife]

If I beak a hose clamp I'll replace them with stronger ones (and document that on my channel), but due to the pivot point they don't see nearly as much torque, plus they are good for hundreds of pounds of force. I have these on a 6KW bike and there are zero issues, but if you don't trust it, go for it. You can add two or three (or more?) if you want but it's overkill. If you really wanted you can use U-bolts, or make your own clamps from thick steel. 🍻

[@bbllrstv13]

Oh no....now you're even making custom beefy torque arms?! Big torque arm really got to you huh? 😂

[@hightech-lowlife]

I totally did this on my own volition, I was not threatened in any way or coerced to make this video whatsoever *blinks twice* 😅

[@bbllrstv13]

@@hightech-lowlife I knew it! 😂

[@hightech-lowlife]

@@bbllrstv13 🤐😎

[@chikararexzpo]

I had the same exact problem when I was using that same exact brand but matte black The drawing process is 48 hours not 24 hours they lying😐 I find that really helps when you put it in a tiny room with a big box fan No light no heat🤨

[@hightech-lowlife]

Yeah I've never seen any paint that stays that tacky after such a long time, most will dry fully within 1 day 👍 Thanks man!

[@merevoyt8265]

I‘m new to mtb riding but what id that for

[@hightech-lowlife]

Really only necessary if you're running a hub motor 👍

[@catlos2006]

🔥

[@hightech-lowlife]

Thanks man!

[@matox01tekk]

tell you what i watched the entire video without knowing what torque arm is or what is it for, so basically i watched the video to find out but i didn't

[@hightech-lowlife]

Thanks for watching, I was going to explain what they are in the video, but I figured if you were looking to build your own then you'd already know what they are and that info would be redundant/annoying 👍 www.ebikeschool.com/torque-arm-need-one/

[@AlaskaBikeDoctor]

What problem is this solving? Also, looks like this adds quite a bit of work to a flat tire repair.

[@hightech-lowlife]

www.ebikeschool.com/torque-arm-need-one/ 100% makes changing tires more of a pain, but hub motors already complicate this, and if you're familiar with that, then this is just another 5 seconds added to the process, pretty easy to take on and off.

[@mihaiiorgu6756]

use some laquer after paint if it's sticky

[@hightech-lowlife]

This particular paint just needs a very long time to dry 👍

[@sgtgotten]

How to Fix a non problem?

[@hightech-lowlife]

Most likely they are not needed, however this build is 6KW, and once you start getting higher up there in the torque it becomes more and more of a necessity.

[@stellaji888]

Once you start doing some high performance mods, you have to make sure you’re safe. These give you peace of mind.