Tektro 203mm Brake Upgrade

[IOUZIP]

I have been working on this brake upgrade for some time. The stock 180mm dual piston brakes are good but I was ready for some better braking power. I was trying to get a set of the Tektro HD-E725 brakes but they have been out of stock for a few months. So I decided to get a the HD-M725 brake kit. I was not going to use the brake levers. I did used the hose and brake calipers. I kept the Star Union brake levers which have the motor cut out switch. Now I am still in the process of rebuilding the bike after some hard trail activity over the last year. 203mm front and rear rotors with Tektro 4 piston calipers. Started with front will add more pictures as it progresses.

Stock 2 piston Star Union calipers next to the Tektro 4 piston Orion 4P calipers.

Tektro brake line fitting screwed right into the Star Union lever.

When you bleed this brake system it was tricky. First used a syringe with Tektro mineral oil brake fluid and the right hose fitting in the caliper. Crack open the cover to the reservoir push the brake fluid up throught the caliper. Catch the overflow with a rag. Raise the caliper level to the lever height and remove the syringe from the caliper. Reinstall the screw in the caliper. You will need to burp the brake lever with little pulls on the lever. Once the air bubbles are gone reinstall the cover.

 

[IOUZIP]

The second bike (wifes) I am sticking with the Star Union 2 piston calipers. That bike has the 100 mm fork I just installed today. Trying to finish the rebuilds tomorrow.

 

[fooferdoggie]

Have you considered getting a 248mm downhill rotor?

The brake rotors keep getting bigger!!

As you know.. the 203mm rotors have been the standard size for MTBs, particularly downhills and trail bikes. But apparently 203mm wasn't big enough, so Magura, Sram, Galfer, Hope and other brake manufactures made 220mm. So 220mm became the standard. Everyone is selling 220mm. And now, they're...

electricbikereview.com

I cant imagine needing that much except for heat. going to the xt 4 piston man my braking is serious strong. Had a 203 on back but I have found no need for it. but then I am not going down

 

[IOUZIP]

Once I started trail riding the rear rotors warped. I have seen many other fat tire ebikes use 203mm and 4 piston setup on front and rear. I use alot of rear brake trail riding and warped a set of 180mm. My 2nd Juiced Ripcurrent S bike has the 203mm rotors but still use the stock 2 piston Star Union calipers.

203mm rotors and Tektro 4 piston calipers with stock Star Union brake levers.

203mm rotors with Star Union calipers.

 

[fooferdoggie]

if your warping rotors its time for better rotors or better cooling. we have ice-tech rotors on our tandem and man they are solid. we have rode the brakes fora couple of miles.

 

[fooferdoggie]

Those Shimano rotors do not have 6 bolt pattern.

I would recommend EBC or Galfer.

Galfer

Performance Motorcycle Braking Systems for Street, Racing, and Off-Road - GBrakes

galferusa.com

EBC

Bicycle Archives - EBC Brakes

EBC Brakes are the leading online brake company offering brakes, pads, discs, rotors for automotive, motorcycle, mountain bike & racing -

ebcbrakes.com

they make them with 6 hole. what works though is they have aluminum um cores so they can move the heat better.

 

[IOUZIP]

I have noticed the brakes are less touchy. When braking it feels more progressive less on/off and less likely to lockup. My butt tells me shorter braking distance when hard on the brakes now.

I did have to readjust the brake lever screws which I did not know I could do. This has allowed me to set the brake levers to the same distance. The rear is now at a different lever distance from the stock 2 piston setup. It's all good now.

When you think about the cost to replace 180mm vs 203mm plus an adapter bracket it really seems like a low cost upgrade for the stock 2 piston setup.

The additional cost of $180 for the 4 piston setup may not be in everyone's budget.

 

[IOUZIP]

I finally got around to testing the front brakes.

Stock Star Union brake levers, Star Union dual piston calipers and 203mm rotors the best stopping distance from 15mph was 16ft.

With the stock Star Union brake levers, Tektro 4P calipers and the with 203mm rotors the best stopping distance from 15mph was 14ft.

I did 4 full stops during testing on asphalt. Front shocks were unlocked. 15psi tire pressure.

Still working on the best rear brake setup for the next test.

 

[Uuzd4S]

The second bike (wifes) I am sticking with the Star Union 2 piston calipers. That bike has the 100 mm fork I just installed today. Trying to finish the rebuilds tomorrow.

View attachment 78367
View attachment 78368

So there I was, looking at how worn my RCS Brake Rotors have gotten this season and wondering why Juiced didn't use Tektro's larger Rotor ?
These 180mm brakes are minimal at best. Mine are getting pretty well worn even though I've only ever used Organic Resin Pad's And . . . was amazed how hard it was to find a Tektro HD-E350 180mm Rotor set . . . over a Year ago. Many searches later AliBaba (the Chinese Ebay/Amazon) produced an original set, which I have.
OK, lets search the "Known Issues" forum with "Tektro Break Upgrade" . . . . . . . : )
I Like It !! . . . haven't read the details or follow-up yet ZIP but if ur willing to do this for the wife's bike . . . nuf said!
Likely I'm gonna put these OEM Tektro's on for the interim or find out they're the wong wun's ; / I'll be back!

 

[IOUZIP]

My current setup: On My RCS I am using 203mm rotors on the front and rear with Tektro 4 piston on the front and the stock star union caliper on the rear. The larger rotors allows for better brake modulation. The NEW RCS Step Thru (wifes bike) has 203mm rotor up front with the stock caliper. Rear has stock 180mm rotor with stock caliper. I did find that adding 4 piston to the rear caused the rear brake handle to feel too soft. That is why I have the dual piston on the rear on both bikes.