Giant Revive conversions

[Cowardlyduck]

Hi all,

So it seems there are quite a few Giant Revive custom/DIY electric conversions out there, and I figured it would be nice to try and bring everyone together to get some discussion going for converting these awesome bikes.

I have done a mild conversion which turned out fantastic:
[youtube]5bkNp0t4W4E[/youtube]
This bike was a fairly low budget/simple setup, but it worked so well I really want to make more!

I can see there are also a bunch of threads on ES for other conversions, most of which are old or very short threads:
Giant Revive, planning a mid motor conversion
Giant Revive e-bike project
Giant Revive project
Giant Revive with Bafang BBS01 & cargo racks
Giant Revive projects??
Greenerwheels Giant Revive Ebike build
4 day Giant Revive RC build for my wife.........
Dee Jays Giant Revive projects
Re-viving a Giant revive
There are even more, but I'm not going to list them all.

Part of the reason I am starting this thread is I now have another Giant Revive I plan to convert, but this one is going to be quite different to anything else out there (I think).


I will discuss further below, but this Revive has a busted rear shock, so I am looking to replace with something longer. I want to make this a 2WD Fat tyre conversion, so will also add front suspension forks. Should be quite the decent adventure bike!

Please add/discuss your Giant Revive build!

Cheers

 

[SlowCo]

I have a Gazelle Easy Glider that I would love to add some sort of electric support to. It has front and rear suspension and a 8 speed Shimano rear gear hub. Great bike but I could use some assist on it so I'll follow this thread :thumb:

 

[Cowardlyduck]

I have a Gazelle Easy Glider that I would love to add some sort of electric support to. It has front and rear suspension and a 8 speed Shimano rear gear hub. Great bike but I could use some assist on it so I'll follow this thread :thumb:

That's awesome!
I didn't realise the Gazelle Easy Glider was even a thing! Had a quick look and they don't seem to be a thing in Australia, otherwise I would love to snag one at some point!

Since most of these kind of bikes run a 20" rear, the best combo seems to be a rear hub motor with batteries mounted in or under the frame to lower and push forward the CG.

Although I want more battery than can fit, I think for my next Giant Revive I will still put battery inside the frame, but just have part inside and part outside. Ideally I would end up with 1.5-2Kwh which I've found to be a good amount for longer ventures.

Cheers

 

[ykuga]

This is interesting topic. I also have a Giant Revive.
First I added disc brakes. Front fork was replaced by Sunlite fork. To add a disc to rear I fabricated a thick Al plate with a disc adapter. Three holes are used for supporting it. Then I added eZee rear hub motor. The battery consists of three 48V 10.5Ah units (from ES Ellectrico) in parallel. Your idea of embedding a battery into the frame is a good thing. My bike with a big battery does not look so good. Currently the controller is in a front bag. I still need to add a torque arm and other items.
One issue of the current setup is that this bike is slow. I get only 20 MPH. I am planning to test a voltage booster (up to 58V) to get higher speed. I hope to get close to 25 MPH. I hope my eZee controller is compatible with 52V battery.

 

[99t4]

Could you fabricate a v.2 of your disc brake mounting plate to include TA functionality? (Might have to be steel instead of Al.) Seems like it could extend further down to encase the axle. Possibly extend it even further to include a pinchbolt below the axle for even better axle securing capability?

Are the rear rack vertical struts attached to anything?

How are you charging those paralleled batteries?

 

[Cowardlyduck]

Thanks for sharing ykuga!

I like the idea of disc brakes, but I've found two alternate solutions that I prefer which is to run a DD hub with Regen, and hydralic rim brakes like the Magura HS11. Combined I have all the stopping power I could need on the rear. For the front a rim brake is usually enough as it doesn't need as much force to lock up. That being said, I recently put a disc brake on my BikeE AT at the front due to running a 16" wheel in a 20" fork so had no other option. Works well!
You might want to be careful attaching Aluminium to the steel frame like that. If it gets wet or damp it could start galvanic corrosion. I would ensure you give it a thick coat of paint at least to help prevent that from happening.

As for the battery, yes it certainly looks better having it inside the frame, but it is limited what can be done with the space. I was only able to fit 10S4P in the one above, so 36V 14AH, which is ok for a low powered geared hub, but definitely not enough for what I have in mind with a 2WD fat bike.

I am thinking I might go with 14S8P for this time around for 52V 28Ah (1450Wh). That way I can stack 2 x 4P cells end to end with wire paralleling them to fill up the frame. I should be able to fit 6S (8P) inside the frame and then will put the remaining 8S (8P) either under the sides of rear rack or on top of the frame (or both). Placing the BMS might be tricky, but I'm sure I'll figure something out.
I need to take another look, but it might also be possible to fit 5 or 6 18650 cells length ways into the frame. If that can work it makes a few other possibilities available like 14S10P or 14S12P for some serious long range capabilities. 8)

I'm curious why you changed the forks? Was it a geometry thing?

Cheers

 

[Cowardlyduck]

I've been following this guy for some time and he has fixed-up a bunch of Revives over the years. Here is his latest electric revive.
[youtube]n6Zxh9djD7o[/youtube]

I am still slowly working towards my next Revive conversion and have a rear motor in a Fat bike rim and controller on the way.

Cheers

 

[LewTwo]

I will discuss further below, but this Revive has a busted rear shock, so I am looking to replace with something longer. I want to make this a 2WD Fat tyre conversion, so will also add front suspension forks. Should be quite the decent adventure bike!
Cheers

There are a couple of people selling NOS (new old stock) GTM 7 shocks on Ebay:

https://www.ebay.com/itm/194146212309 (Los Aangels, California, US)
https://www.ebay.com/itm/255222188721 (Taiwan)

FYI:
It ain't perfect but it closer than anything else I could find (because there is nothing else).
I think that the wheelbase may be short by as much as 10mm. The cheating I did on the seat and handlebar stem are downright shameful but those were NOT the areas that I was concerned with.
I have the original DWG if you can use it.

Edit: If you install a suspension fork then you will jackup the front end by at least three inches (for a 20 inch fork) that already has a bit quirky steering.

Edit Update 22 July 2022: The drawing has been updated with a much more accurate representation of the swing arm. Note that the wheel base has increased in length by about 3/8 inch. I think it may still be 6 to 8 mm short.

 

[Cowardlyduck]

Thanks for jumping over LewTwo!

I haven't updated this thread for a while. I already replaced the rear shock. I tried using a much longer DH DNM shock, but it was too stiff to use and tilted the bike forward too far for my liking so I switched over to an old air shock I had lying around from my old Stealth Fighter. It's perfect for it without any other changes.

I actually just ordered a bunch of parts for my conversion recently. I'm still going Fat, but ditched the idea of 2WD...just too hard and doesn't help much.
The front will have a decent travel (135mm) suspension Fat fork with a 4" tire bringing it up quite a way. Once I load up the rear with batteries I will probably try switching back to the DH DNM rear shock to see how it rides.

I am also currently trying to figure out how to make the rear brakes work. The wide Fat rim I have barely fits past the brake posts and technically it doesn't, but if I angle it in I can make it work. I'll just have to mount the tire after I install the rim.
I'm looking at using cantilever brakes to avoid problems with clearance, but even then I'm probably going to have to modify them to make it all work.
Oh and this is all powered by a RH212 hub, so no problems with clearance etc, but I will have to figure out some torque arms.

Cheers

 

[LewTwo]

Thanks for jumping over LewTwo!

I am also currently trying to figure out how to make the rear brakes work.
...
I'm looking at using cantilever brakes to avoid problems with clearance, but even then ...

Parallel threads. I just got my 20 x 2.25 tire today. Thus I broke down and removed the rear wheel. The spacing between the rear dropouts is confirmed to be 135 mm.

You only have about 60 mm between the mounts for cantilever brakes. If you have a 65 mm (or wider rim) then I doubt that you will get the cantilever brakes to work. You should have plenty of room for up to a 4-1/2 inch wide tire provided the outside diameter does not exceed 24 inches. If I was trying to fit that large a rim, tire and motor then I would cut off the existing cantilever mounts and find a different braking solution (electronic regen, disk brakes or long rope and a anchor).

It might be possible to fabricate some sort of combination disk caliper mount/ torque arm for non-drive side rear drop out (three pictures below). Those rear dropout are thick ... about 7.5 to 7.6 mm (I think that may be 0.1 mm of paint). The second picture below was taken with the camera centered on the axle hole and as perpendicular to the dropout as I could get it. The idea was to be able to trace the front surface outline. Those are 10.0 mm wide vertical dropout slots. I measured the normalized bend angle to be 30 degrees. The small screws are 5 mm nominal diameter.

For minimal induced lens distortion I really should have switched to 600 mm lens length and backed off further ... but I am getting lazy in my old age ...


These are NOT the full resolution images. If you need those then message me your email address.

 

[LewTwo]

Here is what I think is the final version of my Giant Revive OEM specifications file.
Note I also added speed calculations for a hub motor as well as a mid drive
View attachment Giant Revive Bicycle Specifications.xls

 

[Cowardlyduck]

Thanks LewTwo.
I have thought about rear disc brakes. I will have regen, so I don't need much braking force at all on the rear.
I already ordered/have some cantilever brakes so I think I'm going to try and make them work. I'll have to extend the arms and the V of the brake wire, but I think I can make it work.
Failing that, yes I would try using one of those cheap/nasty axle mounted rear disc brake adaptors. They are terrible, but they do work and for something like this, combined with regen, it's enough.

Your spreadsheet is really interesting to me. I actually was just looking at my front chain ring the other day trying to figure out if I should change it to something larger. On my other recumbent bikes I use Schlumpf ATS speed drives to make up for the smaller tire and speed pedalling.
For this bike I don't want to spend too much and was thinking a large chain ring up front will work since I've only got a standard wind hub and the 4" fat tire should mean that my top speed isn't that high and the rolling diameter of the wheel will be closer to 24" anyway. The hub should accept a 11T rear cog also so the pre-existing 48T chain ring my bike has should work well.

Cheers

 

[Chalo]

At the community bike shop where I work, I took a recently donated Revive electric conversion to harvest the hub motor and whatever other components could be repurposed. But the thing had been left out in the weather so long that the hub motor was locked up solid. The nonstandard seat was ragged, and there really wasn't anything left to save.

I have a hard time believing that a bike someone would bother to buy and convert to electric would be left out like that until it was useless, if it had been any good to begin with. I'm open to other explanations, but that's the obvious one.

 

[LewTwo]

I have a hard time believing that a bike someone would bother to buy and convert to electric would be left out like that until it was useless, if it had been any good to begin with. I'm open to other explanations, but that's the obvious one.

Well I can give my reasons (but keep in mind that I am a bit odd duck myself).

1) I want a bike frame where I can get full leg extension, especially for my bumb left leg ... w/o raising the seat up to eye level with 747 pilots. I can not do that with most bikes designed for children and other short people.

2) Pavement maintenance is so poor these days that riding a rigid frame bike on the street would knock my teeth out ... if I had any left. Ever other rear suspension bike I have seen has no way to carry cargo. Some of those full suspension e-bikes even require the rider to carry the battery in a back pack. Just for the record, I would use it with my travoy trailer but at least there is a rack to mount the hitch. Note: I did see one Riese & Muller model that fit the bill but it started at $5,000, had a proprietary Bosh electrical system and even worse, it was pedal assist only.

3) The Revive does appear to have a sturdy built strong frame. The one place Giant did not 'cheap out' was the frame. There must be over a pound of filler rod in those welds. By all user accounts I have read it is an extremely comfortable bike to ride ... once one get used to the quirky handling.

4) My father , may he rest in peace, taught me that reinventing the wheel was almost always a losing venture. I would rather buy/use a manufactured frame than build one from scratch. Maybe I can make the Revive meet my desires .... maybe not but I can at least give it a try.

Lastly, there was damned little information available on-line about these things. At least I can make an effort to remedy that so the next time someone goes looking there is something to be found.

Does that address your question ?

P.S.
The original Craig's list add was for four of them.
The guy that got there before I did bought three.
If I have been foolish then at least I am not the biggest fool.

 

[LewTwo]

For you folks interested in a Direct Drive Hub Motor for the Revive Bike,
I note that Leafbike has 20 inch cast rims kits with up to 1000 watts (stock).
Pricing is in the US$400 neighborhood.
Rims are a tad too narrow for my liking.

https://www.leafbike.com/products/diy-bike-conversion-kit/20-inch-48v-52v-1000w-electric-bike-kit-front-casted-hub-wheel-1009.html
https://www.leafbike.com/products/diy-bike-conversion-kit/20-inch-48v-52v-1000w-rear-casted-hub-motor-electric-bike-kit-1218.html

Golden Motor also has/had a similar rim:
https://goldenmotor.bike/product/magic-pie-20-inch-casted-rim/

 

[LewTwo]

Rims are a tad too narrow for my liking.

I should have looked a bit further before I commented:

 

[Cowardlyduck]

No picture sorry, but I just figured out (by building it) that you can fit 10S4P using 2170 cells inside the frame. It does require a small amount of grinding away some of the rear rack mounts to make the battery slide in without catching, but that is worth it IMO.
I've just done it with some left over 40T cells, but if using some of the higher capacity 5AH cells that would get you 720Wh inside the frame which is awesome!
I plan on doing exactly that for my up-coming fat build.

Cheers

 

[Cowardlyduck]

Just found this classic super corny advertisement for the revive.

[youtube]gaZuVPvbteY[/youtube]

As cliché and corny as it is, at least it did actually talk about some of the technical details. Can't say that about most current advertisements!

Cheers

 

[Warren]

Just found this classic super corny advertisement for the revive.

:wink:

"new shape of 21st century cycling"

"seating position, and posture so advanced"

https://bicycleman.com/wp-content/uploads/challand_1896.jpg

https://bicycleman.com/wp-content/uploads/1905_lg.jpg

 

[Cowardlyduck]

:wink:

"new shape of 21st century cycling"

"seating position, and posture so advanced"

https://bicycleman.com/wp-content/uploads/challand_1896.jpg

https://bicycleman.com/wp-content/uploads/1905_lg.jpg

Haha!
Yeah, nothing is new any more...mind you I would rather ride the revive than those old things!

I'm still planning on building my Fat conversion and have most of the parts except for the battery.
After finding out I can fit 10S of 2070's inside the frame, I'm currently debating if I should just go with 10S4P using 5AH cells to get 20Ah, or if I would rather add additional external batteries as well to get either higher voltage or more Ah....can't decide!

Even better would be if they released a 2070 cell with more than 5Ah.

Cheers