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Chief

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Just don't lean too hard when that knob is contacting the ground...piece of cake.

 

...and don't run Shwalbe tires next time. 😉

Edited by Teamsloan
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That's just one of the reasons I don't run Schwalbe's anymore. They shed knobs like my dog sheds hair. You can try and warranty it but that's a whole other story.

Edited by Chief
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2 hours ago, Chief said:

That's just one of the reasons I don't run Schwalbe's anymore. They shed knobs like my dog sheds hair. You can try and warranty it but that's a whole other story.

Yeah it's probably time for me to make the switch. The MM / NN combo has been unbeatable for me in the traction department, but they definitely don't hold up on the rocky terrain around here. 

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Run schwalbe on wife's bike since they're relatively light for their size and she isn't heavy/fast enough to wear them out. XC= NN&RR  AM= HD&NN

For the rest of us, it's hard to beat a DHF & Aggressor combo. 

 

 

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Had a new one today: Mechanical disc brakes that stick when squeezed anything more than a light drag. Older calipers so I did a full rebuild and got them working smoothly but it did not change anything. I tried it on the bench and the pads won't stick to each other (when adjusted all the way out) but if I put a rotor in between it sticks hard. I even sanded and cleaned up pads and cleaned up the rotor. 

20201003_213327.jpg

Edited by RedRider3141

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10 hours ago, RedRider3141 said:

Had a new one today: Mechanical disc brakes that stick when squeezed anything more than a light drag. Older calipers so I did a full rebuild and got them working smoothly but it did not change anything. I tried it on the bench and the pads won't stick to each other (when adjusted all the way out) but if I put a rotor in between it sticks hard. I even sanded and cleaned up pads and cleaned up the rotor. 

20201003_213327.jpg

Wanna buy a set of Spyres?

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Most of those mechanical disc brakes have a set of three bearings on curved ramps that press the piston toward the rotor. If one of those bearings is dislodged or damaged, it might stick when pushed to a certain point. Those Promax brakes probably suck, but it would be interesting to tear them open to inspect what's going on in there.

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39 minutes ago, mack_turtle said:

Most of those mechanical disc brakes have a set of three bearings on curved ramps that press the piston toward the rotor. If one of those bearings is dislodged or damaged, it might stick when pushed to a certain point. Those Promax brakes probably suck, but it would be interesting to tear them open to inspect what's going on in there.

No that's exactly how it's constructed, but the assembly is smooth and does not bind/stick until you put something between the pads. 

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2 hours ago, RedRider3141 said:

Ended up buying a set of Avid BB5s

I had great experiences with Avid mechanicals.

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Working on my daughters 24" Hotrock. It *had* these rollers above and below the front cog. As I was cleaning up the bottom one because it wasn't rolling the top one exploded. I removed what was left and was able to crush it with my hands, very brittle. Are these just a cooler way of appeasing the layers in lieu of a chain cover? Is there any reason I shouldn't just remove them both? 

20201030_190528.jpg

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1 hour ago, RedRider3141 said:

Working on my daughters 24" Hotrock. It *had* these rollers above and below the front cog. As I was cleaning up the bottom one because it wasn't rolling the top one exploded. I removed what was left and was able to crush it with my hands, very brittle. Are these just a cooler way of appeasing the layers in lieu of a chain cover? Is there any reason I shouldn't just remove them both? 

20201030_190528.jpg

I can’t see the chain ring but I would bet it is not a narrow wide. Those are used as a cheap chain retention device. I’m also taking an educated guess that the bike has a non-clutched derailleur. Removing them will lead to a higher chance of dropping the chain off the front chain ring. If your daughter is just riding around the neighborhood or is only riding easy trails, I wouldn’t worry about it. If she is a little shredder, you’ll want to look into replacing them. You can most likely (hopefully) visit your nearest specialized dealer and they can get you some new ones. 
 

If you do just take the other one off, I do see that the roller is bending the chain. With them removed, you’ll also want to remove an inner and outer link to shorten the chain to prevent chain slack when in the smallest rear cog. 

Edited by WLemke

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1 hour ago, RedRider3141 said:

Working on my daughters 24" Hotrock. It *had* these rollers above and below the front cog. As I was cleaning up the bottom one because it wasn't rolling the top one exploded. I removed what was left and was able to crush it with my hands, very brittle. Are these just a cooler way of appeasing the layers in lieu of a chain cover? Is there any reason I shouldn't just remove them both? 

20201030_190528.jpg

Same thing happened to my son's hot rock. I just took them off. I actually replaced the lower roller with one from a cheap amazon chain tensioner. But if the lower one on yours is still intact, I would keep it. It does help some to keep the chain on, but not much. The tension on the rear derailer is just too loose to keep the chain from slapping around on any bumps.

The bike's drivetrain is hardly better than a Walmart bike. You don't buy hot rock's for their components, you buy them for the frame as they are fairly light and can be upgraded. I replaced the crankset too. 
 

IMG_1371.jpeg

IMG_1374.jpeg

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9 minutes ago, Teamsloan said:

Same thing happened to my son's hot rock. I just took them off. I actually replaced the lower roller with one from a cheap amazon chain tensioner. But if the lower one on yours is still intact, I would keep it. It does help some to keep the chain on, but not much. The tension on the rear derailer is just too loose to keep the chain from slapping around on any bumps.

The bike's drivetrain is hardly better than a Walmart bike. You don't buy hot rock's for their components, you buy them for the frame as they are fairly light and can be upgraded. I replaced the crankset too. 
 

IMG_1371.jpeg

IMG_1374.jpeg

Ugh, you shouldn't have shown me that... I've been in debate of rebuilding this from scratch because she's at least 6 months away from riding it on trails. Luckily she's got a 20" Hotrock until then. 

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Unrelated to your chain tensioner situation but I had something happen at Walnut that had never happened in my ~25 years or riding in Austin.

I got a small rock in my chain. It stuck in and the chain jammed on a back pulley. I thought it was a stick because I could not pedal. Spent a few minutes looking at my chain trying to figure out what was happening. Could not see the rock, just that the chain would not move and pulled the whole derailleur when I put force on it. Weird.

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9 hours ago, AustinBike said:

Unrelated to your chain tensioner situation but I had something happen at Walnut that had never happened in my ~25 years or riding in Austin.

I got a small rock in my chain. It stuck in and the chain jammed on a back pulley. I thought it was a stick because I could not pedal. Spent a few minutes looking at my chain trying to figure out what was happening. Could not see the rock, just that the chain would not move and pulled the whole derailleur when I put force on it. Weird.

Reminds me of the time the cable-end-crimp fell off and got wedged in my rear cassette.  I spent so much time looking for bent teeth, bent links to figure out whyI kept having a skip before I eventually noticed the little thing stuck in there.

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On 10/30/2020 at 7:07 PM, RedRider3141 said:

Working on my daughters 24" Hotrock. It *had* these rollers above and below the front cog. As I was cleaning up the bottom one because it wasn't rolling the top one exploded. I removed what was left and was able to crush it with my hands, very brittle. Are these just a cooler way of appeasing the layers in lieu of a chain cover? Is there any reason I shouldn't just remove them both? 

20201030_190528.jpg

Saw this tonight while browsing and thought of this post.https://www.merlincycles.com/en-us/force-chain-guide-167248.html

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I just ordered a new set of Magura brakes from Merlin. I placed the order on a Sunday afternoon and they were here by Tuesday. $27 for shipping via DHL.

The same day I ordered the brakes I ordered rotors and a bleed kit from Tree Fort Bikes in Michigan (Merlin didn't have any 203mm Magura rotors in stock). Free shipping on that order, but it arrived 2 days after the brakes. I would have paid to get that stuff here sooner but Tree Fort isn't currently offering next day or 2nd day because the carriers aren't consistently able to deliver stuff on time.

I'm sure it depends on what you get from Merlin, but I felt like $27 for 2 complete brakes was pretty reasonable, especially considering their price was about $15 less per brake than anywhere else. Now, if I was ordering a $30 pair of gloves I'd never consider paying $20 for shipping (unless I really needed them in a hurry, of course).

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Mechanical disc brakes feeling crunchy? they are not that difficult to dissect and rebuild. Here's one of my Spyres full of grit and grime mid-operation:

123561013_2078149015653806_8515165202445597439_n.jpg.46c1f3824cde1a945270024b146eeb44.jpg

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Continuing on the brake repair theme.

A buddy of mine gave me some M9000 XTR brakes with carbon levers. Cool right? There's a catch. He's the Seth Buckgnar of Utah and generally breaks everything he touches. These were no exception. The carbon levers had been broken and replaced on numerous occasions and in the process, the 2mm hex on the lever reach adjustment/master cylinder pushrod had stripped. Ended up pulling them apart only to find shimano doesn't offer any parts for these and my only option was to buy a new lever/master assembly or repair it. Since i'm stubborn AF, I bought a replacement lever and shit rigged it by hammering a T10 torx into the 2mm hex receiver. That stupidity distorted the threads to where the lever wouldn't thread back on. Had to die the threads and ever so carefully put it all back together. I can say without hesitation, putting that snap ring back in was one of the most infuriating things ive ever done on bike repair.

All back together and ready to upgrade the old XT 785s on the wife's bike.

 

 

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Edited by ATXZJ
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I can say without hesitation, putting that snap ring back in was one of the most infuriating things ive ever done on bike repair.
All back together and ready to upgrade the old XT 785s on the wife's bike.


I hate snap rings, especially when they’re for a brake lever.


Sent from my iPhone using Tapatalk

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