[CalebJ]

I just picked up an SX500 used the other day. From a quick glance, I think the front rotor is a bit warped. When i started looking around for a replacement, I ran into discussions of 2 vs 3mm replacement rotors. I'm out of town at the moment so i can't check, and that led down the rabbit trail of other brake options. Has anybody used the complete hydraulic brake packages like this one?
AKANTOR Zoom Hydraulic Disc Brakes Mountain Bike Sets MTB Front & Rear Set with Floating Disc Rotor 160mm & Color Bolts https://www.amazon.com/dp/B088194H1K/

I'm not absolutely sure it matches up on the bolt pattern for the rotors and such. If it does and offers a decent upgrade for a reasonable price, I'm tempted.

Any feedback from those that have been down this road before is appreciated!

 

[Falkon45]

I haven't had the chance to pull the rotors off any of my mountain bikes to check and see, but I'm pretty sure the mtb rotor bolt pattern should work, as long as your bike has the 3 bolt hub. If it's 4 bolt, it shouldn't work. Also, make sure you have enough space to fit a 160mm rotor. Almost all these bikes are 140mm rotors.

 

[Falkon45]

I actually looked up the bike. lol. Yes, the MTB brakes will fit. You'll have to use the adapter that comes with it. Looks like you'll have space to fit the 160mm rotor. If you're willing to spend a little extra, you can use the caliper and adapter I used for my bikes.

Check this thread:

RSF 650 Hydraulic brake upgrade

So I have been searching the net for a decent brake upgrade kit for my RSF 650, but I don't know if I'm looking in the right places. I see a few kits on Amazon, but they seem to be somewhat sub-par. I'm not really sure of what the brake specs are on my RSF. If anyone could share a few links to...

www.pocketbikeplanet.com

 

[CalebJ]

Thanks! I've read through that thread. So you think the one I linked would fit out of the box?

 

[Falkon45]

You'll need the adapter I bought also. But, check your rotor size, just to make sure. Sometimes it's etched or stamped on the rotor. You'll need a +0 for the 140mm rotor, and a +20 for the 160mm rotor.

 

[CalebJ]

Quick update - the rotors on my SX500 (and I suspect the MX500/650) use a non standard 48mm bolt circle rather than the conventional 44mm pattern. I'll try to find more info tomorrow and update the thread, but for now - the link I posted above definitely doesn't work. The rotors don't match up to the stock pattern.

 

[CalebJ]

I ordered a set of these to try:
Bike Brake Rotors, Mountain Bike 160mm Amazon.com: Bike Brake Rotors, Mountain Bike 160mm Threaded Hubs Brake Disc Rotor Flange Adapter with 6 Bolts : Sports & Outdoors

 

[CalebJ]

What does the controller do with the input from the stock brake lever switches? The hydraulic kit doesn't have any obvious provision for mounting switches. I'm going out on a limb that the controller is just designed to cut power to the motor if either switch is closed, so I can just leave it alone?

On a related note... if I wanted to create a functional brake light, does anyone have a suggestion on how to implement a switch on the new brake setup?

 

[Atvrunner2]

The brake switches is great for a kid. Usless for adults. Mine were cut long ago. As far as a brake light I would have to do some digging.

 

[CalebJ]

The brake switches is great for a kid. Usless for adults. Mine were cut long ago. As far as a brake light I would have to do some digging.

Thanks - so the controller expects them to be open circuits, i.e. the connectors can just be left unplugged? Just wanted to make sure I don't need to jump the wires.

Also, to clarify - this is actually for my 7 year old.

 

[Atvrunner2]

Yep, unplugged its all good. Thats also how to test real quick if no power gets to the motor. They are common to fail.

 

[CalebJ]

I ordered a set of these to try:
Bike Brake Rotors, Mountain Bike 160mm Amazon.com: Bike Brake Rotors, Mountain Bike 160mm Threaded Hubs Brake Disc Rotor Flange Adapter with 6 Bolts : Sports & Outdoors

Good news is that the rotor fits the bike.

Bad news is that's -one- rotor. I completely missed that the first time around. So now the brake upgrade project has gone from the original $70 plan up to $90 and now to $110.

This appears to be the same part from Electric Scooter Parts:

160mm Disc Brake Rotor BRK-518-2M

160mm Disc Brake Rotor 2mm Thick160mm OD37.2mm ID5.5mm ID Mounting Holes24mm Adjacent Mounting Hole Distance (Center To Center)48mm Mounting Hole Bolt Circle Diameter (BCD)

cart.electricscooterparts.com

It's a bit cheaper there, but you pay shipping so it's a wash depending on what else you need. Since I'm also grabbing a couple of bits for the 1800w brushless/lithium conversion, I'll probably order from ElectricScooterParts this time around.

 

[Atvrunner2]

Yes, I always oder from them but wait until I need a bunch if stuff. Save on shipping

 

[CalebJ]

It would be great if there was a way to adapt to the 44mm bolt pattern so we could use the same rotors as everything else does (44 is essentially an international standard). But that may not be realistic.

 

[Atvrunner2]

Yeah, not yet anyway. I can't say there wouldn't be a market for it but no one will probably make that jump to design something.

 

[CalebJ]

There's definitely not a viable market for designing and selling. I was more day dreaming that the right combination of parts might exist with enough research.

 

[Falkon45]

Wow!! I didn't think they'd go as far as to use a different bolt pattern. Good thing is, the mounts used for the brakes are standard with MTBs. Just a heads up, the rear brake may not work. Something I forgot to mention. It's pretty universal for bicycles, but it's different for the mini bikes.

 

[CalebJ]

Different in what way?

 

[Falkon45]

The rear brakes are mirrored from the front, and the mounts are built to reflect that. So, the bicycle brakes will bolt up, but the caliper will sit above the rotor and not make contact with it. You can make it work, but you'll have to drill new holes in the rear brake mount to get it to work.

 

[MrKitty]

The last guy that did it laced mountain bike hubs into BMX rims that's how he got the mountain bike rotors to work on his MX650... Apparently the stock front tire fits a 16-in BMX rim I don't remember what he did for a back tire... I remember he used a downhill mountain bike front fork as well so as far as the front end went the perch and everything was already there lined up ready to go if I remember right he welded a new perch for the back.