Hello
Imot truck looks wierd, dosent motice before today.
I wil tale some picture.
What can i do?
Get a new one, that shit looks warped beyond repair
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I feel dumb for needing to ask but can I run sHFI on an OG focbox single at 12s?
I think shifi needs the phase filters to work properly and I don’t know if v4 had that
It seems like I’m not the first to ask but I can’t seem to find a clear answer on this, how would one go about figuring out belt length with idlers? Is there a formula?
I imagine I’m not the first person to run boardnamics XL precision mounts (100mm c2c ±10mm), dual 636 bearing (6x22x7mm) idlers, and 15/72 gearing, can anybody say from experience what size belts work?
Guess. If your guess is wrong, chop it up and
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Unfortunately there’s no easy formula. If you already have a belt, you can use Brian’s method^^.
You can get an approximation by using string or maybe a thin strip of cardboard (you want a bit of thickness, so paper is less preferable) wrapped around the pulleys and idlers, but it won’t be perfect - might be off a tooth or two.
You can spend a bunch of time and effort in CAD drawing up your pulley arrangement and calculate the path length that way, I’ve done that once or twice.
Or you can take a guess and buy like eight sizes of belts, and pick the one that fits best. Also done that once or twice.
I use this calculator on sdp-si’s site
For your setup:
So you need an 88 tooth belt. 88 x 5mm = 440mm belt.
Probably one or two sizes up if using an idler.
You can adjust it to a 90t belt (450mm) and see that the center to center distances is now 106mm, still within the 100mm +/- 10mm.
EDIT:
I have the same mount, using an idler, on 20/36
Calculator shows a 335mm belt at 100mm. I’m using a 345mm and I’m about in the middle of the adjustment, so adding about 10mm to the belt length to accommodate an idler seems about right.
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or this:
or this:
https://boundmotor.com/electric-skateboard-belt-length-calculator/
boundmotor didn’t pay me to say that, just sayin’
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What’s everyone’s thoughts on TB motors nowadays? These were pretty cheap at $70+ domestic shipping… I don’t mind all the vents since it’s going on a street build.
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I used have a set of those motors, they were champs, worked great for a long time
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Those motors aren’t bad. They’re not the best motors anymore but were at a point in time.
There were also many iterations of those same motors, and the later ones are a lot better than the earlier ones.
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I had a set of the 74s that were brand new and tried to kill me with broken windings… be careful
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I’ll open them up and inspect before installing… Thanks. When did you buy the 74s?
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2-3 yrs ago now
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Is there any sort of standard when it comes to phase wire length and what is a good length? obviously they will be long enough to connect and allow for as far over as I can get the truck to turn to each side, but how much longer should they be past that minimum length?
I just don’t want to have to make them longer in the future if I am not considering another important factor
Make sure they have enough slack on them so that they aren’t pulled tight when the truck is at full lean.
By full lean, I mean remove the bushings and see how far the hanger will rotate before it comes to a hard stop somewhere. You may never need that slack in day to day riding, but if you have an impact on one of your wheels, you can reach that full lean point pretty easily.
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I thought the focbox had phase filters and that’s why it could run FOC at 12s
I second this. This exactly.
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