Adding a motor kit to one of these Giants...

[ejphotos]

Looking to add a motor kit - more than likely a BBSHD - to one of my Giant Trance bikes (both full squish). Was also looking into the CYC setup as well.

My two options: 2021 Giant Trance X 3 29



This one has a BB92 press fit bottom bracket, so I would need the correct size - both brands offer that, also with spacers. As you can tell, not much space on the downtube inside the triangle for a battery - so if I were to install on this bike, I'd probably have to mount the battery on the top tube, or, fab a rear rack mount that would attach to the seat tube.

My second option is a 2004 Giant Trance 4 (26 inch wheels)



This has a 73mm bottom bracket. Again, not much space on the downtube, although there is slightly more room in there due to design.

Goal is to be able to commute 21 miles to work (one way), so I'd need a decent size battery. Thinking 52v with around 14 or more amp hours.

I'd prefer to use the first one, as it's just an overall bigger, more comfortable bike, with much larger and powerful brakes and a bigger suspension (150mm travel F/140mm R) with a slacker headtube angle.

Anyone have experience with adding a motor kit to either bike?

[73Eldo]

I think there are some threads here with that model, not sure which sizes or years and I seem to recall some of the build threads are lacking in critical details and the original posters are no longer around to ask questions. Just looking at the photos the blue one looks like a better choice for fitting the motor. A Luna Wolf may just fit, you can download and print out a template from their catalog page. Also the 3x drive generally implies a little more room and leeway in the chain line. If they changed the design at all for the 1x you could end up with more spacers which kicks the chain line out further and there may not be room for an offset chain ring if it was all designed around that tiny 1x ring so you end up only being able to use the highest gears which may not be the end of the world for a commuter but isn't ideal.

Battery off the seat post just doesn't seem like a good idea but maybe for a commuter you could get away with it but still one curb could be too much for it or even the seat post since they are not really designed for serious loads in that direction.

21 miles one way as long as you can charge at work should not be a problem. As long as you are doing some pedaling and average speeds in the mid teens 2 miles per amp hour seems to be a good ballpark number. Its a big ballpark so its just a starting point, you won't know for sure till you get out on your bike and ride it where and how you will be riding it. 3 miles per hour is pretty good. Some people can do 4 but thats about as ideal as it can get with a light person on a light bike on a rails to trails trail that is flat with minimal stops and traffic. You put a fat guy on a fat bike in a busy urban area that 2 is a lot more realistic with these mid powered bikes. You take that guy and do throttle only and want to average closer to 20 mph 1 mile per amp hour may be difficult to hit.

[ejphotos]

I think there are some threads here with that model, not sure which sizes or years and I seem to recall some of the build threads are lacking in critical details and the original posters are no longer around to ask questions. Just looking at the photos the blue one looks like a better choice for fitting the motor. A Luna Wolf may just fit, you can download and print out a template from their catalog page. Also the 3x drive generally implies a little more room and leeway in the chain line. If they changed the design at all for the 1x you could end up with more spacers which kicks the chain line out further and there may not be room for an offset chain ring if it was all designed around that tiny 1x ring so you end up only being able to use the highest gears which may not be the end of the world for a commuter but isn't ideal.

Battery off the seat post just doesn't seem like a good idea but maybe for a commuter you could get away with it but still one curb could be too much for it or even the seat post since they are not really designed for serious loads in that direction.

21 miles one way as long as you can charge at work should not be a problem. As long as you are doing some pedaling and average speeds in the mid teens 2 miles per amp hour seems to be a good ballpark number. Its a big ballpark so its just a starting point, you won't know for sure till you get out on your bike and ride it where and how you will be riding it. 3 miles per hour is pretty good. Some people can do 4 but thats about as ideal as it can get with a light person on a light bike on a rails to trails trail that is flat with minimal stops and traffic. You put a fat guy on a fat bike in a busy urban area that 2 is a lot more realistic with these mid powered bikes. You take that guy and do throttle only and want to average closer to 20 mph 1 mile per amp hour may be difficult to hit.

Yeah, I am concerned about the chain line and have been looking at the options - and it appears the CYC motor has a better chain line variance pre-spacing. I know Lekkie makes offset chainrings for the setups, and I probably would only stick with a 36t chain ring.

If I were to put battery on a rear rack, I'd mount the rack to the actual frame seat tube and not the post. Although top tube is still an option.

It's flat where I live, and most of the commute is on a rail trail. I'd mostly be pedaling, but using throttle through certain sections. I weigh 220 pounds, so there's that. I do pedal pretty quick though.

[ejphotos]

Printed out some battery templates of various batteries and put them in the triangles of both bikes. Surprisingly enough, both bikes had the same amount of room in the triangles on the down tube. None of the templates gave enough room.
the Trance X 29er has a significant amount of room on the top tube, so I think I'm gonna go that route.
Also did some inspection around the chain ring. There's plenty of room for a much larger chain ring that won't hit the chain stay, so that is good.
All that being said, I think I might look more into the CYC X1 Stealth motor, as the mounting brings the motor in front of the chain ring, instead of below it. It'll also allow me to easily fit it to bottom bracket shell, as well as keep the same chain line.

[zmarkjam]

I built up a 2005 Giant Trance 4 in early 2017. It is by far the most fun and capable trail bike I've built. I purposely sought out an XL frame and the triangle is able to fit a 52v 24ah triangle battery.
Dead simple to build, no spacers or press fit adapters to fit the motor, no re-routing cables from under the bottom bracket, suspension isn't high travel but is very plush. Easy to carry an extra backpack battery. I've heard of some having to grind off tabs near the bottom bracket or grind down interfering suspension pivot points. None of that with this frame. Also, chainline is perfect with Luna Eclipse 42 chainring. Here are some pics. Good luck with your build. Mark

[ejphotos]

Nice build zmarkjam , good info too. Yeah I can tell that XL frame has much more room in it than my medium frame.
it is a fun bike, mine is very plush too. When I got it last year, it was new old stock - never been ridden. It had V brakes and a heavy Manitou coil spring clunker of a fork. I put hydraulic disc brakes on it and a Rockshox Recon Silver TK air fork on it, what a huge difference that made. Rides very well and is great on the trails. However, I do prefer my new Trance X. :)

[Dshue]

The 2021 Trance should be 148mm rear spacing so chainline should be easy to get right as long as the motor can fit up against the bb with very minimal or no spacers.

[ejphotos]

The 2021 Trance should be 148mm rear spacing so chainline should be easy to get right as long as the motor can fit up against the bb with very minimal or no spacers.

Correct, it has boost spacing. Planning to go with the CYC setup, with the body made for the BB92. No spacers required, and the electric motor won't hang straight down, it'll be out in front of the chainring.

[ejphotos]

So, I'm actually going to be adding a rear wheel motor to the older Giant Trance (the blue one). Picked up a cheap Voilamart 1000w rear wheel kit that I wanted to put on an old Giant Yukon, but the dropouts just weren't cooperating. Turns out the dropouts on the Trance are perfect for it. Got to get a few things to make it work. Picking up a 9 speed freewheel sprocket to keep existing RD on it (Voilamart has the threaded freewheel and comes with a 7 speed sprocket). Also picking up a set of 180mm rotors and brackets, that way the rear caliper body clears the hub motor. Should be fun!

[ejphotos]

Well I put the hub motor on. That didn't last too long. It was fast, but not efficient- it's either all full power or nothing. It was also heavy and the rear spokes didn't seem strong. They kept creaking. Here's a picture with the hub motor setup.



So I decided to put a BBS02 setup on it. 48v battery unfortunately didn't fit inside the frame so I had to mount it under the down tube. Fork can compress about 80% before it tire hits the battery, so I don't take this through trails, but I can finesse it on and off curbs still.
This is a much more efficient setup. 9 levels of assist. I can get about 30 miles range if I'm on assist level 4 (keeps it at like 17 mph). I'd like to look into getting a custom battery made that will fit inside the triangle that will give me much more capacity.
Here's a photo of the setup.

[73Eldo]

Wow eyeballing the first photo I would have thought there was room under the tube for a battery but seeing that pack there its a lot tighter than it looks. Did you print out a Wolf template? Those seem to fit places sharks don't and you don't need the extra space to slide them in and out of the cradle.

I also really don't like the look of that rear hub motor. If you get a battery into the triangle and maybe a Lekkie chain ring the mid drive will look pretty sharp. I like its looks better than the hub motor as is. You would think its just software that effects the on and off feel, strange that they can't get that right.

[ejphotos]

Wow eyeballing the first photo I would have thought there was room under the tube for a battery but seeing that pack there its a lot tighter than it looks. Did you print out a Wolf template? Those seem to fit places sharks don't and you don't need the extra space to slide them in and out of the cradle.

I also really don't like the look of that rear hub motor. If you get a battery into the triangle and maybe a Lekkie chain ring the mid drive will look pretty sharp. I like its looks better than the hub motor as is. You would think its just software that effects the on and off feel, strange that they can't get that right.

Yeah I might try to see if it fits on the bottom side of the top tube within the triangle. If it fits there, and there is enough room to spare, I might just order a 52v 17.5 ah battery

[Retrorockit]

You might look into tuning that fork for less travel. if it's coil spring you can put a hard plastic rod inside the spring to limit travel. If it's air Rockshox makes "Tokens" that can be stacked up in the air chamber to make the fork more progressive so it won't bottom out. The thing I would worry about is bottoming the fork when turned, and then locking up the wheel by hitting the side of the battery.
Up to about 20mph the small hydraulic front brake should be OK. But if you plan on going 25-30mph, which that bike can do, then a DH rated front brake would be a good idea. That almost always will be 4 piston caliper. The failure mode for small hydraulic brakes is boiling the fluid with loss of braking.