# Few questions from a newbie in e-bike



## XxTripodxX (Jul 30, 2020)

Hello, how are you guy's doing ?


I'm new in the forum, and i came here looking for help or tips because i want to convert my Trek Marlin 6 M/L 29" Wheels 2020 model to an e-bike. (really can't afford a trek e-bike ready to go..)


First of many question to come... and please don't be to hard on me as english is not my primary language and i use translator and corrector  ... 


I'm riding mostly in my city streets, and bike path (paved and un paved), and some Gravel roads.
I might wanna go later in MTB trails locally, but don't have the fitness to go uphills for a long perdiod of time, that's why some assist, would be cool...


Here is some of my questions..


- Should i look for Fronthub, rear hub or Mid-Drive ??. (i'm 265 Pounds Btw, if you need to know if that change something)


- What wattage would suit me better ? 250W-500W-750W-1000W more??? ( I would have got a 250W mid-drive as i saw most trek e-bikes have shimano or bosh mid-drive and are only 250W ..)


-Something i have a hard time understanding, is that the crank set on my bike is a Shimano M315, 36T/22T, 175mm length But...
I see that most of convertion kits available are 44t up to 52t and i see nothing less then that, isn't 44T too big ??
(SPECS on TREK mention that Max chainring size 1x: 32T, 3x: 42T) i'm confused...


or is there is a way to convert and keep my 36/22t ?


-also if you can tell me by experience what to avoid, it would be cool.


that's about it for now . If someone is willing to help me, i would be really happy.


Thanks for your time!


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## BrentD (Jul 1, 2006)

The Bafang mid-mount motor kits would be the way to go in this case. You can get them varying power levels.

https://www.bafangusadirect.com/bafang-750w-bbs02-mid-drive-motor-and-battery-p/60.htm


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## dundundata (May 15, 2009)

The chainring is going to be attached to the motor on a mid drive, you will not be using your current cranks. You can find alternatives to the stock chainring that the motor comes with. The motor on a bafang for instance will push your chainline out a bit so you should get more clearance than your current crankset allows.

Keep in mind the specs don't always tell the full story, for instance watt ratings are usually nominal and not peak. Some motors may have more efficient design with better internal gearing.

I would get the most powerful motor you can. If you get a hub motor then you probably want rear for more power. You can keep your current crankset in this case.


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## Old & Slow (May 3, 2020)

Post a photo of your bike at the BB. The frame geometry at the BB is critical for the Bafang and other mid-drive motors.


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## rangeriderdave (Aug 29, 2008)

From what I understand ,if you want to ride real mountain bike trails (not dirt roads) the mid mount motor is the way to go. If you look at all the production mountain bikes ,(the ones made to trail ride)they have mid motors.


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## XxTripodxX (Jul 30, 2020)

Old & Slow said:


> Post a photo of your bike at the BB. The frame geometry at the BB is critical for the Bafang and other mid-drive motors.


I'm not sure what BB mean, are these specs helping you ? I highlighted mine

Thanks!!


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## XxTripodxX (Jul 30, 2020)

rangeriderdave said:


> From what I understand ,if you want to ride real mountain bike trails (not dirt roads) the mid mount motor is the way to go. If you look at all the production mountain bikes ,(the ones made to trail ride)they have mid motors.


Awesome, i will definitively go with Mid .

Thanks


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## dundundata (May 15, 2009)

Bottom bracket	VP BC73, 73mm, threaded cartridge, this should work fine with mid drive.


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## XxTripodxX (Jul 30, 2020)

dundundata said:


> Bottom bracket VP BC73, 73mm, threaded cartridge, this should work fine with mid drive.


Great! thank you for the info!!


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## Old & Slow (May 3, 2020)

XxTripodxX said:


> I'm not sure what BB mean, are these specs helping you ? I highlighted mine


BB stands for bottom bracket (the bearings that carry the crankshaft).

In order to install any mid drive motor the BB must be removed and replaced by the motor driveshaft. The crank arms and pedals are attached to that driveshaft. The actual motor is connected to the driveshaft by a pinon and gear. That motor is large and can hang down in harms way depending on the frame geometry.

If your frame is identical to your diagram, then you're in good shape.

Adding a mid drive to a non-ebike always carries the risk of a low hanging motor. Unlike purpose built ebikes which have a custom frame to enclose the mid-motor.


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## dundundata (May 15, 2009)

i have bafang and use the bracket from Luna to secure the motor, you definitely don't want it to move around and smash the frame (especially BBSHD). I would also recommend to protect the frame with something at any point where the motor could touch.

it's not an elegant solution like the purpose built frames. bafang does make an ultra motor you simply bolt on but you'd need a whole new frame.


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## XxTripodxX (Jul 30, 2020)

dundundata said:


> i have bafang and use the bracket from Luna to secure the motor, you definitely don't want it to move around and smash the frame (especially BBSHD). I would also recommend to protect the frame with something at any point where the motor could touch.
> 
> it's not an elegant solution like the purpose built frames. bafang does make an ultra motor you simply bolt on but you'd need a whole new frame.


Good to know, thanks again Dundundata !!

I guess i will finally have to wait a while, i lost job cauz of covid, and i learned from my doctor this afternoon that i might have heart issues.... i'm scared as hell now to go biking :cryin:


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## XxTripodxX (Jul 30, 2020)

XxTripodxX said:


> Good to know, thanks again Dundundata !!
> 
> I guess i will finally have to wait a while, i lost job cauz of covid, and i learned from my doctor this afternoon that i might have heart issues.... I'm scared as hell now to go biking :cryin:


Well folks! i had good news today , my heart is fine! nothing to worry about! 

Now i will start to save money to be able to buy my kit next spring, because winter is coming soon here, so not much days left to ride ...

I'm going to get the Bafang BBS02 750W mid motor

This is the kit 
https://www.amazon.ca/dp/B083LMV4WY...CDD&language=en_CA&psc=1&ref_=lv_ov_lig_dp_it

Any advice on what display i should choose ? there is 9 models... :eekster:










And 44-46-48-52 T ??
12ah, 14,5ah or 17,5ah Hailong battery ? 

Bit confused here










Thanks for the help!


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## Old & Slow (May 3, 2020)

The 965 or the other B&W display. Color display, even if back-lit, are often impossible to read in bright light.

You might want to wait for the 11-11 sales for the motor. There's a YouTube video on the subject.


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## XxTripodxX (Jul 30, 2020)

Old & Slow said:


> The 965 or the other B&W display. Color display, even if back-lit, are often impossible to read in bright light.
> 
> You might want to wait for the 11-11 sales for the motor. There's a YouTube video on the subject.


Thanks! haven't think about that ! and i will look for that video , might be interesting!


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