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Electra Straight 8 Brake Options

J

jdbauman

1 W
Joined
May 4, 2007
Messages
57
Location
Temecula, CA
I just purchase a used Electra Straight 8 to convert to electric. I love the look of this bike. I want to put a bafang BBSHD mid drive system on the bike. I noticed however that the bike only has coaster brakes on the rear wheel, the kind that stop you when you pedal backwards. It has no brakes on the front wheel at all, and it does not have the holes required to install a disk brake. I don't think the rear coaster brakes will be adequate after conversion to electric. Does anyone have any ideas on front brake options that might work on this bike. Thanks!
 
BR7240.jpg


Would something like this work on the front hub. I guess I would probably have to re-lace my front wheel onto a hub that would be compatible with this right?
 
Adding a rear disc brake will be difficult, since the bike is aluminum, and welding on it will ruin it's annealing.

So keep the rear coaster brake, and look to the front brake. Most of the really effective braking is the front wheel anyway. The front fork is steel, so a half decent welder can pretty easily attach a tab of metal for a disk brake mount to the front fork. Then of course, new disc wheel.

Or, simply replace the fork, with one that has brake mounts of any type.
 
You will lose the coaster brake if you use the BaFang BBSHD, it free wheels. Meaning you can't put backwards pressure on the chain/hub there is a freewheel clutch in the motor so rear brake is going to be real tricky with that system and bike.
There are bolt on disc brake adapters that could be mounted to the bike, but you would need a new disc compatible hub as well.
The easiest way for you to get a brake up front would be a drum brake. I've used a 90mm Sturmey Archer drum that was effective upto the 40kph area I'd ride in. I don't think I'd want to up the speed much further and have it be my only brake though.

Couple pluses.
It was the easiest brake system I've installed and set up.
I think it would suit the look of a Straight8 perfectly.

Good luck on the build
 
Yeah, typed fast, brain fart...forgot frame heat treatment...

The rear disc brake mounting adapter in the link above looks interesting, but I've never tried it. If you do try it, and it seems to work OK, perhaps consider bonding it with Dr Bass's recommended Scotch-Weld DP-420? I'm not suggesting that this is the "best" rear disc adapter, and even if I settled on this one, I might drill and bolt it to the broad and flat drop-outs. If using a rear hub (you mentioned a mid drive, but others are reading this too) I'd have to cut out the slot alignment nubs...

505223505223reardiscbrakeadapter1.jpg
 
I am hesitant to "recommend" this front disc brake adapter, but I have one on order to experiment with. It is always best to upgrade the entire fork to a unit that was designed to handle disc brake loads.

038.296192954_std.JPG
 
With the money you're going to be investing in it between the motor and battery, upgrading to a fork with a disk brake mount and a disc ready wheel won't add too much to the cost, and will be worth every penny during the first hard stop for a car that's cutting you off..

You're still going to want some kind of braking in the back too... you don't really notice it usually, but without some drag back there during leaned over braking in slippery conditions the back will slide out so hard as the load shifts up to the front wheel. That is exactly what led to one of my longer pavement slides, on a path I knew like the back of my hand, during a surprise rain shower, with a new motor set up that I hadn't gotten around to hooking up a back brake on yet. Luckily it was winter, and long pants and a jacket took most of the punishment, but still left a pretty good amount of skin behind.
 
Sturmey drum brakes are also an option if you're going to end up swapping hub/relacing. the 90MM drums have as much stopping power as most disc brakes and they don't need pad replacement... good deal!

you can also get their IGH units with the drum brake integrated. I've been meaning to try out their new "heavy duty" 5 speed IGH with drum, sounds like it could work with a mid drive (supposedly more reliable than their previous generation).

drum hub in the front is a good option if you decide to keep the original fork.
 
As Brentis mentioned, the rear coaster brake will not work with the Bafang. You'll need new brakes.
And that means you will need to replace hubs and re-lace the wheels to fix the problem.

For the rear, you could try a bolt on Disk adapter. But Drum brakes are easy to fit and work great. And while fitting one, it would be easy to fit an IGH, making the bike far more useful. the Sturmy-Archer 5 speed drum brake is a great setup. I've had one for years. http://www.niagaracycle.com/categor...XW-DE36t0VqiExv3MQM_KkI6aALqyfxZngaAhiS8P8HAQ

For the front, Drum brakes are good options, or you could replace the front fork and fit a disk. I would avoid bolt-on disk brake mounts with front wheels. If the bolt on adapter fails, it could jam the wheel. On the rear, that would be an inconvenience. On the front, that risks being fatal.
 
Drunkskunk said:
... or you could replace the front fork and fit a disk.
Click to expand...
That is what I would do. A good used fork with IS mount would make the bike better and safer.
 
I went through this with a Trek Pure. I tried a Sturmey Archer drum brake and a 3 speed hub. It was OK. In the end I converted that bike to a front wheel drive and the coaster brake and regenerative braking are great.

My best decision was to buy a new frame with hand brakes. YMMV

I still have the SA 3spd with drum brake mounted in a Alex rim. My other SA tsp held up to a BBS01. Sadly the wheel gathers dust as n one wants a 3 spd.
 
The newer Electra Straight 8 models come with front disc brake and a choice of 3-speed or 8-speed rear hub. It would work pretty good for a geared front hub motor. Since you already have your bike, maybe you could call Electra support number and ask how to buy one of the forks from the newer model.

http://www.electrabike.com/bikes/cruiser/straight-8-3i?g=mens
 
Hmm, Perhaps since only thick plate got hot, it's ok. Sure don't want to change the temper of any aluminum tube.

Looking at that picture, I can see how it would be possible to make a steel brake mount, and bolt to the thick aluminum plate on those bikes.

The electras, they have some of the most generous and strong looking rear dropouts I ever saw.

I feel really dumb not realizing a bafang would not work with a coaster brake. But as you can see, a hub motor gives you a disc brake wheel in back.
 
nicobie said:
About 4 years ago I welded some tabs on my townie for rear disc brakes. No Problems yet.
Click to expand...
Well done and on my favorite frame. Such comfortable rides!
 
Chop up a cardboard piece and take it to your local waterjet or laser cutter. Use the rack tabs to secure it.
Add some structural adhesive after roughing the surface as backup if desired.

Here's an electra townie I did with a Mxus 4500.
https://www.instagram.com/p/wE_tXQnFaI/
https://www.instagram.com/p/wYvTRwHFfH/

Drill your disc tab holes last. Although using a small radius of 38 and 78mm from axle center you can estimate the space needed to drill later on your cardboard mockup.
http://blog.artscyclery.com/wp-content/uploads/2014/12/iso.jpg
 
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