Rank Newbie to convert a 2005 Trek 7200 FX Hybrid

ace5000

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Hello,
Any help would be appreciated! This is for running around the city streets maybe 20 miles round trip, mostly flat some inclines.

I'm looking for a reliable kit - speed is good!
Rear hub kit is best, yes?
I did see one on Amazon - Ebikeling??? Any good?

The trek has 700x35C tires
750 Rims
11-32, 8 speed x 3
1/2x3/32 chain

Thank you!!!
 
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Hoggdoc

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I have the same exact bike, spent a couple of days looking at all the various kits and what it would take to do a good conversion to the bike came to the conclusion that it was better to buy a ready-made E bike.

There are so many things you would need to change on the Trek to make it safe such as converting the brakes to disc brakes which would require a new front fork, new front wheel with appropriate hub and as well as buying the rotors & calipers.

The set up I specked out was about $1000 not counting any special labor necessary and not converting the brakes. I chose to buy a HIMAWAY all-terrain cruiser. It is much heavier than the converted bike would be but it has the advantage of the huge 4 inch wide balloon tires.

You asked about the Amazon kits, you have to be very careful there and do a lot of investigation so you know what you're buying & what you should buy. The cheap kits and cheap batteries will not work out well I feel quite sure.

I don't know if that helps you at all. But that's the information I can pass on to you from my own experience.
 

Frogslayer

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Would you go with a rear hub bike? My budget is under$1k...
I have two bikes that i converted with violamart rear hub kits and cheapo Ebay blue lithium batteries. I get 20 mile range with no pedaling if i wish. One kit has been on 2 bikes and just always works. One cheap batteries did burn out a bms once but it was only a $12 fix. If you can use a soldering iron and a multimeter i wouldn't be afraid to go cheap diy, you'll have a lighter and faster machine for it for way less $. You can get a 48v1500 watt brushless direct drive hub with heavy spokes and a double wall rim with a controller for just over $200. You may have to tighten a few spokes and file some sharp edges on the axle where the wire exits, maybe they'll be fine though. With a little love it will run. It will be another $200-$300 dollars for a 20 amp hour battery or larger battery that has enough discharge capability to supply your controller with the power it wants. This setup can hit 34mph but i typically cruise around 15 to 20 mph.
 

ace5000

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That would be great but I have 700cc wheels and searched to no avail. There are Ebikeling kits I looked at. Also I have std. friction brakes. Would it be dangerous without disc brakes?
I also have a 750w restriction in Ohio...
 

Frogslayer

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Keep your brakes adjusted and watch for pad wear and you'll be totally fine. Especially at 750 watts.
 

ace5000

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Thank you all for your input!
I'm ready to pull the trigger on a Bafang 48v 750, 860C display mid-drive for 700cc wheels on Ebay or Amazon. There is a choice of pedal gear sizes of 52 48 46T. It is mostly flat around here but are some extended grades. I weigh 210lbs. Your thoughts on the gear size?
 
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Frogslayer

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Thank you all for your input!
I'm ready to pull the trigger on a Bafang 48v 750, 860C display mid-drive for 700cc wheels on Ebay or Amazon. There is a choice of pedal gear sizes of 52 48 46T. It is mostly flat around here but are some extended grades. I weigh 210lbs. Your thoughts on the gear size?
No clue, i almost never pedal lol.
 

ace5000

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I bought the Bafang 48v 750, 860C display mid-drive and runs amazing.
 

MWRider

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For 700C tires, Bafang says 44T chain ring. That is what I put on my 750W 48V BBS02B mid drive on Trek FX 7.2 Hybrid. I weigh 196#. My wife has the 500W w/48T chain ring and is 70# lighter. She just pretty much leaves on the 4th cog, set a max speed of 15 mph and just cruises with a big smile on her face. We are both using the stock Trek linear pull brakes. They work fine.
 

ace5000

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Thanks, any special sizing or installation issues?
Not really fit very well. The spindle was a bit tough getting out and had to beat and cut it a bit. I put on a new chain, good brake pads and wider tires. This thing is a rocket. My advise is keep your mouth closed when up to 30 mph... haha. Let me know if you need anything.
 

arthurdent18610

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Hello,
Any help would be appreciated! This is for running around the city streets maybe 20 miles round trip, mostly flat some inclines.

I'm looking for a reliable kit - speed is good!
Rear hub kit is best, yes?
I did see one on Amazon - Ebikeling??? Any good?

The trek has 700x35C tires
750 Rims
11-32, 8 speed x 3
1/2x3/32 chain

Thank you!!!
If you want to keep the gearing, a rear wheel kit is the way to go, cheaper too & simpler to fit. You can buy rear hubs with rotor fittings, so you can use your existing brake system, a little fiddling is necessary as these kits are universal & where they fit one bike without any problems another can be a right pain in the rear. I use a mid-drive Bafang 750w with a 48v 15.5ah YOSE triangular battery, what with a bit of cycling & sensible use of the assist settings I can twenty miles with ease, I'll be fitting a larger battery later probably on the rear rack or pannier fitted one each side, good luck with your build Rob (UK)
 
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