Beginner Question Thread! 2023 Edition

Hello, I attached a video showing my issue with the Uni1 V2 paired with the UBOX V2. Acceleration is not consistent and if I push for full throttle sometimes it does not give throttle whatsoever. Brakes work completely fine. I have previously used this motor controller with a VX2 with no issue. So far I have went through the exact pairing process that Spintend shown in their video and even re-flashed my motor controller to start from fresh still with issue. I also looked in the data analysis and the wheel is detecting the position just fine if I give say 85 percent it registers on the vesc tool that I am giving 85. The remote firmware is 1.02 and I am using Spintends 5.03 firmware for the UBOX. I also tried binding it with the receiver that came with the Uni1 instead of the built in receiver still with the same effect. Any people have similar issue?

Now there is an old mount!

Looks like it’s meant to use an idler since the motor is fixed

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Idler pulley is just a pulley that sits on the shaft right, spinning along with the shaft?

You can use a bearing or two as well

Still some pics on the old Ollin site

orevolverdd2

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Neat! might do that in the future. I want it up and running as soon as possible. It has been too long in the making! Ordered a motor pulley 15T and a 36T wheel pulley along with a 295 mm belt. Also 4 larger wheels.

Don’t match your pulley to your belt. Get the pulleys right first, THEN get whatever size belt you need. HTD5M synchronous timing belts are cheap.

Also, just in general, paying attention to order of operations will help you immensely.

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I wish I knew about the OOP before I started a few years ago haha. I have learned a lot though. Even though I got it in a mixed order, I will get it done. Next up is the helmet :stuck_out_tongue: but then I should just need to program the vesc and plug the connectors of the system in and it should work. The pulley kit I bought came with a belt of my choosing so if it doesn’t fit, it’s not a big deal as you said I can get them cheaply

If you have a belt that doesn’t fit or a broken belt, you can slice it lengthwise in half and use it to find the size of the belt you need. On the first try, with no mistakes or math.

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Thanks :slight_smile: I will do this if it turns out it doesn’t fit when I get it

Just realized that I could have 3D printed both pulleys and tested for the length of the belt via your empirical way

u need an idler in the middle to make it work, usually u find the “perfect” belt length, then u +5mm to account for the idler placement. when u install the pulleys, the belt will be loose, and u need to use the idler to adjust the belt tension

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Ah, so the function of the idler (the ball bearing) is to adjust the belt tension? What if the belt is tensioned enough when it is attached? or can that never be the case, because I wouldn’t be able to attach it without it being loose enough that it can fall off? I think I see how this is used

The idler also increases the tooth engagement; the belt will be in mesh with a slightly larger number of pulley teeth.

A lot of folks including myself though prefer not to use them.

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u need the belt to not skip once when u hard accelerate / brake, if u can have such a belt with ur ratio, then in theory, it should work without an idler

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So, this requires an idler because the mount is long? Shorter mounts would not need this? Or perhaps uses another tightening mechanism like moving a piece of the mount to or away from the wheel pulley to loosen or tighten?

Anyway, I think I should get an idler since that’s the type of mount I got. I didn’t get one with my mount

And out of curiousity, you guys prefer not to use them because it’s more work than necessary?

Non idler mounts allow you to slide the motor to adjust belt tension. With an idler mount, you use the idler to adjust tension. Tension is super important.

image

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not because the mount is long, but because there is no adjustment on the motor screws, for example, BN motor mount had the slot u can slide the motor back and forth so u don’t need an idler

image

dang it, sniped by @jaykup

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I’m only one person that prefers not to use them, but for me they are additional failure points, they make it more difficult to select belt sizes, it’s more weight, and I haven’t seen much better results using them.

Belt alignment is also important.

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ah I see. That seems like a better design. Easier to deal with it seems like.
Not sure I can get a hold of an idler for this specific mount either. I guess I could 3D print something and combine with a ball bearing

both have their pros and cons, but i’d say most of us use the slot design, and if they need more teeth engagement, then u can add an idler on it (as long as the mount support an idler)

u don’t really need any thing special, just a screw, nyloc, few washers, and either one wide bearing or two bearings

don’t forget if u have two bearings next to each other, put a thin washer / shim in between

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