Other Trek rail 5 brake and rotor mismatch from new

[Cannafish]

I bought a Trek rail 5 as my first eMTB and now a couple of months later I'm pretty used to it. I love it, it has opened up a new world to me. However. The brake lever travel has started to bug me. Upon investigation and research the Tektro orion 4p brakes are to be matched to 2.3mm rotors and my bike came with 1.8mm rotors. Meaning the brake lever travel before the pads bite the rotor is excessive-1 1/2". Is this common? Should I be expecting the 2.3mm rotors?

Any advice here would be great. Cheers in advance

 

[irie]

If the problem is reach then Google search says this:

"To adjust the reach on a Tektro Orion 4P brake lever, you'll need a 2mm hex key. Locate the reach adjustment screw, which is inside the brake lever body. To increase the distance between the lever and handlebar, turn the screw clockwise; to decrease it, turn it counter-clockwise. Fine-tune the adjustment to your preference."

 

[Cannafish]

If the problem is reach then Google search says this:

"To adjust the reach on a Tektro Orion 4P brake lever, you'll need a 2mm hex key. Locate the reach adjustment screw, which is inside the brake lever body. To increase the distance between the lever and handlebar, turn the screw clockwise; to decrease it, turn it counter-clockwise. Fine-tune the adjustment to your preference."

I have adjusted the reach. It's the length of pull before the pads hit the rotor. It's about 90% of travel.

 

[Bear-uk]

I have adjusted the reach. It's the length of pull before the pads hit the rotor. It's about 90% of travel.

Perhaps they need a quick bleed?
The pads adjust automatically on the hydraulics to the rotor thickness and pad wear provided the system is completely full and with no air in it.
Your thinner rotor should not make any difference. But as the pads move out and stay in the correct position then the fluid level will drop in the reservoir.
So that's why a bleed could solve your problems out

 

[Highland Wheels]

Sounds like they just need a decent bleed.

 

[Stihldog]

The Tektro brake system is relatively good for a Rail 5. It’s an entry level brake system suitable for the Rail 5 but may not be suitable for some EMTB style of riding.

I suspect a lever bleed is necessary to eliminate any trapped air which may have been overlooked during assembly. Then the lever can be adjusted to suit your lever position. (Distance from the grip).

Rotor thickness generally doesn’t have any factor in lever position or stroke length. Your hydraulic system adjusts for that. But a thin rotor can have warp easily from excessive heat.

Types of brake pads and types of rotors dissipate heat generated during long descents or hard braking. A thin rotor might be okay for some styles of riding.

I would do a lever bleed then adjust the levers as suggested by @irie.

I assume your bike is fairly new so master cylinder and calliper should be okay …I hope .

 

[irie]

I would do a lever bleed then adjust the levers as suggested by @irie.

Yes, that's the next thing to do - very easy and quick.

 

[Cannafish]

I've bled them. It was the first thing I did before adjusting the reach. The free stroke is 2 inches/50mm. I have two inches of lever travel before the pads touch the disc. There is no sponginess to the brakes. When they bite to fully locked up is about 5mm. I don't have a problem with the brakes working efficiently, they do. But I have to have the reach adjustment fully backed out or the lever travels almost to the bar before the pads touch the rotors. I've bled the system twice and the lever travel remains the same. My pads have at least 2mm clearance from the rotors. By the time they touch the rotors my lever has gone through 50mm of travel before the bite point.
I will try another bleed but I feel like I'm just wasting mineral oil as I haven't found any air as yet.

 

[Bear-uk]

I've bled them. It was the first thing I did before adjusting the reach. The free stroke is 2 inches/50mm. I have two inches of lever travel before the pads touch the disc. There is no sponginess to the brakes. When they bite to fully locked up is about 5mm. I don't have a problem with the brakes working efficiently, they do. But I have to have the reach adjustment fully backed out or the lever travels almost to the bar before the pads touch the rotors. I've bled the system twice and the lever travel remains the same. My pads have at least 2mm clearance from the rotors. By the time they touch the rotors my lever has gone through 50mm of travel before the bite point.
I will try another bleed but I feel like I'm just wasting mineral oil as I haven't found any air as yet.

Next thing to try then is to remove pads and see if the pistons appear to be moving out ok then fit something thinner than the pads into callipers.
Keep pressing brake lever to get the pads to stay into the new position that's too tight for the pads to slide in.
Then prize pistons out slightly until the pads will go in but end up slightly tight.
Then go for a ride. The levers will probably hardly move to start with, but after a while should sort themselves out and work ok.

 

[Cannafish]

Next thing to try then is to remove pads and see if the pistons appear to be moving out ok then fit something thinner than the pads into callipers.
Keep pressing brake lever to get the pads to stay into the new position that's too tight for the pads to slide in.
Then prize pistons out slightly until the pads will go in but end up slightly tight.
Then go for a ride. The levers will probably hardly move to start with, but after a while should sort themselves out and work ok.

That sounds like a plan! Thanks. I will get onto this and report back. Fingers crossed.
If this doesn't work I think I'm going to go with Shimano XT levers...

 

[Stihldog]

I just bled my only Tektro brakes today (lever bleed only) and had some success. I also adjusted the position for the rear brake lever using the small Allen screw adjustment. (Good enough because this is not one of my main bikes).

Did I mention that I hate Tektro Brakes?

Because the rear calliper is fairly high, air can become trapped and cause lever issues. The bike must be almost vertical and the master cylinder must be the highest point for the initial bleed and possibly for a lever bleed.

I would not use these brakes on my other bikes for more than tame trails. (I use Magura MT7’s but some other brands are good.




A special adapter needs to be used with the bleed funnel. I used shimano mineral oil. PITA. I think I’m a Magura fan-boi.

 

[Cannafish]

Next thing to try then is to remove pads and see if the pistons appear to be moving out ok then fit something thinner than the pads into callipers.
Keep pressing brake lever to get the pads to stay into the new position that's too tight for the pads to slide in.
Then prize pistons out slightly until the pads will go in but end up slightly tight.
Then go for a ride. The levers will probably hardly move to start with, but after a while should sort themselves out and work ok.

Wooooohoooo!
Reading what you said, in between the lines a little. I took off the front caliper, put a credit card between the pads and pumped the lever to clamp the card. I then used the card to open the gap enough to reattach the caliper. Now my lever free stroke has gone from 50mm down to 10mm. My brake feel is now spot on. I've adjusted the reach to bring the lever back closer to the bar. My front brake now feels virtually perfect. I'm going to repeat this procedure with the rear brake and go out for a ride.
Bear-uk: thanks heaps bro

 

[Cannafish]

Both brakes are now vastly improved. I get better feel and improved braking power with both one and two fingers. I'm guessing the levers could use a top-up of fluid. I think bleeding them from this point will get them really spot on. For these brakes.

Thanks everyone.

 

[Bear-uk]

Both brakes are now vastly improved. I get better feel and improved braking power with both one and two fingers. I'm guessing the levers could use a top-up of fluid. I think bleeding them from this point will get them really spot on. For these brakes.

Thanks everyone.

This must be the first time someone has taken any notice of what I've said in years
Glad it's worked out for you.
Btw I've fitted xt servo wave levers to my magura 5s and it's improved them

 

[irie]

Wooooohoooo!
Reading what you said, in between the lines a little. I took off the front caliper, put a credit card between the pads and pumped the lever to clamp the card. I then used the card to open the gap enough to reattach the caliper. Now my lever free stroke has gone from 50mm down to 10mm. My brake feel is now spot on. I've adjusted the reach to bring the lever back closer to the bar. My front brake now feels virtually perfect. I'm going to repeat this procedure with the rear brake and go out for a ride.
Bear-uk: thanks heaps bro

I've posted before about the above 'trick' which I sometimes use but forgot to mention it here, my bad

Edit link: Brakes - feel & long level throw.

 

[Stihldog]

I've posted before about the above 'trick' which I sometimes use but forgot to mention it here, my bad

Edit link: Brakes - feel & long level throw.

I wonder if a bleed-block and a cleaning would have a similar effect? I use bleed blocks for cleaning Magura and Shimano brake callipers.(4 pistons ). The plastic card trick sounds easy for Tektro brakes. (Probably restore my faith in Tektro brake systems).

 

[irie]

I wonder if a bleed-block and a cleaning would have a similar effect? I use bleed blocks for cleaning Magura and Shimano brake callipers.(4 pistons ). The plastic card trick sounds easy for Tektro brakes. (Probably restore my faith in Tektro brake systems).

Try it and post the result here. YKIMS.

 

[Cannafish]

I wonder if a bleed-block and a cleaning would have a similar effect? I use bleed blocks for cleaning Magura and Shimano brake callipers.(4 pistons ). The plastic card trick sounds easy for Tektro brakes. (Probably restore my faith in Tektro brake systems).

I feel that I could improve them further by using a thinner piece than a credit card. I will give it a go today. We have horizontal rain and 100km/h wind here today in NZ

 

[Bear-uk]

I feel that I could improve them further by using a thinner piece than a credit card. I will give it a go today. We have horizontal rain and 100km/h wind here today in NZ

Perfect riding weather

 

[Cannafish]

Now my brakes are back to feeling a bit spongey and they squeal. Very loud. I hate these brakes