Reddit reviews GRIN Front Torque Arm for Mounting on Forks with Fender Eyelets. Thick 1/4" Stainless Plate

If you already have a bike to convert and you don't want to skimp on quality too much, you can probably do it for around $600.

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Plan for around $250 for a direct-drive motor kit, though you might be able to get one for cheaper if you shop around. You'll need to check a few things to make sure you get a kit that fits your bike:

Wheel size - Match this. Don't try to stick a kit with a 26" wheel on a 29er, for example, unless you know what you're doing and you're explicitly trying to alter the handling characteristics of the vehicle.

Brake type - It's getting rare to find a kit that isn't disc brake compatible, but it's still worth checking to make sure.

Dropout spacing - The vast majority of front hub kits are designed to fit in forks with 100mm dropout spacing, and rear motors are built for 135mm dropout spacing. This won't be an issue on most bikes, but some folding bikes will have narrower spacing, as will many older bikes (90s and earlier, mostly). Also keep in mind that these cheap motors use old-style solid axles, so they're only compatible with bikes built for solid axle or QR. A few thru-axle motors exist, but they're not cheap.

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For the battery, you don't just want to buy the cheapest thing available. Many of the cheapest lithium packs use unbranded or mystery-brand Chinese cells, which often tend to not meet the stated specs, wear out faster than expected, and in extreme circumstances, might even be less safe than a pack built with name-brand cells. LunaCycle and Em3ev are probably the largest and most reputable sellers of high-quality ebike batteries, but if you're on a very tight budget, UnitPackPower is a good, more budget-friendly option, as long as you keep in mind that they sell packs with unbranded cells alongside their packs with good cells. Shop carefully, get a pack with good cells, and make sure you get a pack that can handle the power that your chosen motor kit will demand.

For example, here's a 48v10Ah pack from UnitPackPower for $300 that uses either Samsung or LG cells (probably just whatever is cheaper at the time, but they're both good cell manufacturers), and is rated for a continuous power draw of 25A, making it suitable for most "500w" or "750w" rated motor kits. This battery should be good for around 20 miles of range at 20mph, or 13 miles at 28mph.

Note: All kits peak well over their stated wattage, so take their rating with a grain of salt when choosing a battery. If you buy a 48v 750w motor kit and pair it with a battery that can only handle 16A continuous output, you're going to have a bad time.

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And finally, remember to include a torque arm in your budget. There are a lot of flimsy knockoffs out there, primarily of a design that was found to be defective and subsequently discontinued by GrinTech back in 2010, so avoid those. If you're not sure what to get, you can't go wrong with the GrinTech V2 or V3 for front hub motors, or the V4 for rear hub motors.

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Add a few dollars for some wire and wiring connectors (if you buy your motor kit and your battery separately, they're very unlikely to come with matching connectors), and you'll be good to go for around $600.

It seems that your comment contains 1 or more links that are hard to tap for mobile users.
I will extend those so they're easier for our sausage fingers to click!


Here is link number 1 - Previous text "V2"

Here is link number 2 - Previous text "V3"

Here is link number 3 - Previous text "V4"



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^Please ^PM ^/u/eganwall ^with ^issues ^or ^feedback! ^| ^Delete

I donno I'd pick a 36v kit from https://www.electric-bike-kit.com. Not that I have any person experience with either.

In the past Dillenger had some pretty bad customer support. They could of gotten better since then, though.

Either way you probably will be fine.

These small hub motors are convenient and lightweight, but are not barn stormers. They should get you close to 20mph on flat ground and help you up hills if you pedal along with them.

The only thing I would recommend as a add-on to your bike is get a torque arm. For low-power setups it's not strictly necessary, but it'll protect your bike from damage.

https://www.amazon.com/Grin-Technologies-Universal-Version-Electric/dp/B00K57N9II/

or

https://www.amazon.com/Torque-Mounting-Fender-Eyelets-Stainless/dp/B00JOUOPY4/

Damn that's exspensive for a single torque arm.

Edit: here's one I found on Amazon for $22. This one is also Amazon prime. https://www.amazon.com/gp/aw/d/B00JOUOPY4/ref=mp_s_a_1_2?ie=UTF8&qid=1486946223&sr=8-2&pi=AC_SX236_SY340_FMwebp_QL65&keywords=ebike+torque+arm&dpPl=1&dpID=51eDhO7xPbL&ref=plSrch

Amazon also has one for $37 that comes with two torque arms but it's not prime.

https://www.amazon.com/gp/aw/d/B00WY7EGUC/ref=mp_s_a_1_1?ie=UTF8&qid=1486946223&sr=8-1&pi=AC_SX236_SY340_FMwebp_QL65&keywords=ebike+torque+arm