Mechanical disc brake upgrade

Parts and accessories for your bike
Forum rules
Stay on topic. Be courteous.

Mechanical disc brake upgrade

Postby metalman302 » Sat Sep 16, 2017 12:34 pm

Just a few days ago I bought some Shimano BR-M375 calipers to replace the junk JAK ones. I check the price on AliExpress, Amazon, and eBay and $30 shipped for the pair was the cheapest I found. Then today I'm browsing AliExpress and the same calipers have dropped in price by almost half to $16.38 shipped for a pair :cry:
Budget Bike Riders - Facebook group
metalman302
 
Posts: 299
Joined: Mon Oct 03, 2016 12:52 pm

Re: Mechanical disc brake upgrade

Postby rudiger » Mon Sep 18, 2017 7:37 pm

What was it about the JAK brakes that caused you to replace them?
rudiger
 
Posts: 28
Joined: Sat Aug 11, 2012 9:02 pm

Re: Mechanical disc brake upgrade

Postby metalman302 » Mon Sep 18, 2017 10:54 pm

Mostly screeching. Others with the same bike had the same bike had the same problem. Also the other day when I went to readjust the stationary pad, the adjuster was suddenly loose in the bore. The reviews on Amazon had several people who had replaced their JAK or their Zoom brakes and they said these were silent and a huge improvement in power.
Budget Bike Riders - Facebook group
metalman302
 
Posts: 299
Joined: Mon Oct 03, 2016 12:52 pm

Re: Mechanical disc brake upgrade

Postby rudiger » Wed Sep 20, 2017 10:23 am

I went ahead and ordered the Shimano BR-M375 caliper pair from Aliexpress for $16.38. Thanks for the heads-up on what seems like a good, cost-effective way to upgrade grungy OEM calipers. Just a complete set of replacement pads, alone, are at least $5.

I think my original calipers are the cheapest ones possible: they use round pads and the backs of the calipers are a solid piece, unlike rectangular pad calipers where you can view the pads/disc from the top. Maybe they're somewhat better in that water is less likely to get in from the open back? All I know is that the round pads seem to have a lot less surface area than the rectangular, meaning less stopping power.

I did notice an odd thing when ordering the calipers. A pair were $16.38 but they listed the front caliper for $11.88 and the rear as $13.88. Seems strange that the price would be different between the front and rear. Wouldn't the calipers themselves be exactly the same? Then there's the small difference in price when getting a pair. Who wouldn't pay the small difference and get two of them instead of just buying one? I'm wondering if there's an error on pricing for the pair.

Regardless, thanks, again, for the info.
rudiger
 
Posts: 28
Joined: Sat Aug 11, 2012 9:02 pm

Re: Mechanical disc brake upgrade

Postby dddd » Wed Sep 20, 2017 4:28 pm

I replaced my rear JAK caliper with this Br-M375 caliper and the difference is huge, there is no noise at all now, and the braking is smoother and stronger.

I replaced the front caliper with an avid BB7 caliper, which has more positive "bite" than the M375 caliper, but it does honk moderately when used with any force. Nowhere near as noisy as the stock JAK caliper tho, and the action is smoother and much stronger.

I paid at least $20 for one of the BR-M375 calipers, and it was worth it! I got the BB7 caliper for free, it was used, and I willingly paid $20 or so for a new set of pads for it.

My brakes feel great now. I will change my rear rotor to 180mm like I did on the front already. Then the M375 should be a more perfect match for the front.

The Jak calipers use a setscrew to hold the stationary side puck adjustment, which makes a simple job less simple. It takes both a 5mm and 2mm Allen key to do the job, while the Avid caliper is tool-free and the M375 caliper used just a 5mm key, since the rotation is indexed with a spring detent to hold the adjustment as on the Avid (which has a plastic knob that you turn with only your fngers).

Anyway the JAK calipers are miserable for serious riding, especially on steep grades (or where traction is sketchy since they are grabby). Throw 'em out.
dddd
 
Posts: 521
Joined: Tue Dec 29, 2015 12:04 am

Re: Mechanical disc brake upgrade

Postby rudiger » Wed Sep 20, 2017 6:01 pm

How necessary is it to switch the rotors from 160 to 180 with the BR-M375 calipers? Is there any significant detriment to contnuing to use the 160 rotor?
rudiger
 
Posts: 28
Joined: Sat Aug 11, 2012 9:02 pm

Re: Mechanical disc brake upgrade

Postby Tomcat65 » Wed Sep 20, 2017 6:38 pm

It's only as necessary as you feel. Larger rotors increase the feel of power in your brakes. If your 160mm discs are plenty to stop you and your bike, then there is no reason to go larger. I like 200mm front and rear because I feel it adds modulation, which makes it a little easier to control my braking pressure. It might just be in my head lol.. But a larger rotor increases the leverage at the disc. Very similar to shifting down to a lower gear, it takes less effort to stop the bike, the larger your rotor. Necessary? That is totally a preference call
Tomcat65
 
Posts: 1535
Joined: Mon Jun 23, 2014 3:12 pm
Location: Western Kentucky

Re: Mechanical disc brake upgrade

Postby metalman302 » Wed Sep 20, 2017 8:23 pm

If I'm not mistaken, the front and rear calipers themselves are the same, just the included front vs rear mounting brackets are different.

Glad you got to take advantage of the deal. If in the odd chance it was a listing mistake I'm sure they'll make it right. I may even pick up another pair for the Stat.
Budget Bike Riders - Facebook group
metalman302
 
Posts: 299
Joined: Mon Oct 03, 2016 12:52 pm

Re: Mechanical disc brake upgrade

Postby rudiger » Thu Sep 21, 2017 1:55 pm

Do you know what's different between the front and rear caliper brackets? They look identical on my bike. The distance between the attachment bosses seems to be an identical 2", as well.

Likewise, I'm not enthusiastic about the convoluted process of ordering something through Aliexpress. Seems quite 'iffy' when compared with the smooth ordering procedure of, say, Amazon. So, I guess that's the trade-off for the much lower price.
rudiger
 
Posts: 28
Joined: Sat Aug 11, 2012 9:02 pm

Re: Mechanical disc brake upgrade

Postby rudiger » Thu Sep 21, 2017 2:03 pm

Tomcat65 wrote:It's only as necessary as you feel. Larger rotors increase the feel of power in your brakes. If your 160mm discs are plenty to stop you and your bike, then there is no reason to go larger. I like 200mm front and rear because I feel it adds modulation, which makes it a little easier to control my braking pressure. It might just be in my head lol.. But a larger rotor increases the leverage at the disc. Very similar to shifting down to a lower gear, it takes less effort to stop the bike, the larger your rotor. Necessary? That is totally a preference call

Thanks for the explanation. I'll probably stick with OEM discs for the time being unless something happens (warp) or am able to score larger discs at a good price (like the good price for the Shimano BR-M375 calipers).

I am a little curious on what (if any) adjustments or modifications are needed to fit larger discs. I would think the caliper would need some kind of shim to take it far enough out for a larger disc? Or is enough space allowed in OEM caliper brackets for any size disc? I would imagine that, at some point, shims would needed for a disc beyond a certain diameter.
rudiger
 
Posts: 28
Joined: Sat Aug 11, 2012 9:02 pm

Next

Return to Components

Who is online

Users browsing this forum: Bing [Bot] and 3 guests