OK, so this might get a little long winded, but here goes. Is it too much to fucking ask for "bike reviewers" to actually read the fucking manual and properly bleed brakes before "testing" them? Is it too much to ask that OEM bike assembly factories read the same fucking manual and properly new brakes on the bikes they're assembling? Why do brake manufacturers misleadingly call the leverage adjuster the contact adjuster?
I say this because of a few reviews I've seen this year of the Maven brakes, compared to my experience now owning 2 pairs. Yesterday, Vital posted a brake test roundup backed up by using Brake Ace data acquisition system - cool! Except that in the bleed process they describe for both the Code and the Maven, they say they only did a top bleed, and that while doing that they rolled the contact adjuster all the way in (which is 100% opposite of what SRAM says you should do - full out). In their feel impressions, they mention that the rear had an inconsistent bite point sometimes while skipping over compressions. Well, no shit - you did a half-assed bleed, and that's exactly what a brake will do if you have air in the system. Then, this morning those knuckledraggers at Loam Wolf post their Maven review and complain about the same feeling, on various test bikes they've had come through with Mavens on them, and also whining about how hard it is for them to pull the levers. Which is pretty amusing considering how they're all big ~200 lb guys and much stronger than little ol' 165 lb me.
So there's a couple of issues going on here. First, the Maven is a big chonky brake with lots of volume, nooks, and crannies for air bubbles to get trapped in. It uses mineral oil, which in my experience is more sensitive to absorbing air prior to and during the bleed, but longer lasting once you get a good bleed. The SRAM bleed manual for the Mavens is quite thorough, and if you actually follow it, there's a really good chance you'll have a solid bleed the first try. I had a little bit of vagueness on 1 of my 4 brakes after the first bleed that went away after a second pass (noticed bubbles right from the start of the second bleed). The second big issue here is the term "contact adjuster." Don't get me wrong, the adjuster on the SRAM (and other brands who implement it) brakes is a really great tool for helping the rider make the left and right brakes feel the same. The problem is that what it actually does is change the leverage of the brake, adjusting the starting point of where the lever pushes on an eccentric cam. So when it's set all the way "out", it has less leverage and is more linear, meaning it feels like the throw is shorter - at the cost of also needing more finger force to achieve the same amount of stopping power. When the adjuster is wound all the way "in", the lever becomes more progressive and has more leverage, resulting in a longer pull but requiring less finger force. Think short vs long pry bar. The problem is that with the label "contact adjuster" people don't understand the tradeoff, and you get people who want a really quick engagement because that's how some other brake they used felt, then they whine about how hard it is to pull the lever without ever bothering to try the other setting ("contact" all the way in). On the other end of the spectrum, you have Hayes with a really light but long lever pull (due to its leverage design, and also no real functional "contact" adjuster), and you get idiots like myself asking questions on forums trying to figure out how to shorten the throw.
In contrast, look at the review from Blister on the same brake system. They noticed some erratic behavior in the brakes and rebled them carefully and the problem went away. Their review describes this, which is good information for someone considering the brake. Similarly, they talk about the effect of the contact adjuster after finding that they were getting bad arm pump running it all the way out.
I'm not trying to say that Mavens/SRAM are perfect. I'm not trying to say that all bike reviewers are idiots. I'm just disappointed at the lack of attention to detail that some of these "reviews" have. And I think that brake manufacturers are doing themselves a disservice by the way they label the "contact" adjuster. And probably need to do better at getting training on properly bleeding to bike assembly factories, because if they do a shit job, consumers are going to blame SRAM/Shimano/Magura/etc. for a shitty brake.
well ya man but you usually only need half a bleed![]()
I asked if one is going to get setup to spew some brake fluid, why not just do a full bleed ? Well apparently usually its only necessary to do 1/2 a bleed, so what if it doesnt work now do you thro it away or bleed the whole brake and wouldn't it just have been easier to bleed the whole brake system when you were all setup for it the first time, how much time did you save here
Last edited by XXX-er; 10-30-2024 at 01:13 PM.
Lee Lau - xxx-er is the laziest Asian canuck I know
More of a PSA than a rant:
Wow, TSA has stepped up their game. For the last three years, I have been able to smuggle a co2 cartridge inside of my aluminum one up pump no problem. Got busted and called back to the check in desk, had to show them how to open it, and remove the co2. They were cool, but holy crap, that’s next level xray.
Did have to go through security again, where they really looked through things.
Forum Cross Pollinator, gratuitously strident
Demos that aren’t set up properly. My 5’2” wife demoed a bike today. It had 800mm bars and they set up the suspension with 25% more psi than they should have.
I guess a pump might kind of look like some kind of pipe-bomb to the eye trained to look for such things.
Forum Cross Pollinator, gratuitously strident
God yes, especially the wide bars. Last year I visited my BIL in Asheville and rented a bike to ride there - same as the one I own, just different parts. But the one thing that fucked with me endlessly was the 800mm wide bars on a size medium instead of my normal 760. I ended up just shoving the controls (and my hands) in an inch and resigning myself to tagging every tree along the trail with the bars.
top bleeding sram brakes is stupid and ineffective most of the time. If you use the technique seen in the maven bleed video that Sram makes, it is an extremely quick process already. The Loam wolf guys are rad riders and I like their content about riding qualities of different frames, but their actual technical understandings of things like this leaves a lot to be desired.
Ibis demos their SMALL bikes with 800mm bars. Clearly they have no intention of selling their small and mediums.
I was at Absolute Bikes in Salida for their 25th Anniversary Party. Chris Cocalis, owner/founder of Pivot, was there. A tech was setting up an XS Switchblade for my wife to demo and Cocalis walked up, pulled off the grips, shifters, and brake levers. He then grabbed a saw and set up to shorten the bars. The tech nervously said, "We're not supposed to do that with a demo."
Cocalis looked at him, said, "It's an XS. Who do you think is riding it?" and continued.
I assume companies leave the bars full width, expecting the dealer to trim to the customer. You can always cut. You can't add.
I don't have Mavens but I should watch that vid^^
I will watch a half doz you tubes on a subject to arrive at concensus on a procedure i need to perform, so there are all kinds of how-to's on bleeding my Guides, there are 7 vids a page/ 10 pages so 70 guys wearing golf shirts with logos all have a very slightly different take on getting the bubbles out, I settled on some kid with hair like Lyle Lovett and it worked fine
I think there are another 10 pages of Shimano bleeds so thats 140 how to's and thats only 2 brands of brake so far
Last edited by XXX-er; 10-31-2024 at 11:18 AM.
Lee Lau - xxx-er is the laziest Asian canuck I know
OR just use lock-ons that will slide anywhere you want
I'm not big but I have wider shoulders and 800 works fine for me but so did 760,
I'm probably just an insensitive bastard
Lee Lau - xxx-er is the laziest Asian canuck I know
Same applies to demo bikes with too much pressure in shock, fork, and tires. Shop bros assume beginners shreds like they do? I can't tell you how many 150# novices and low intermediates got bikes with 40psi in their 2.5s, and 120psi in the fork.
Or how about XS and S bikes with 175mm cranks? XL and XXL bikes with 125-150mm droppers? LOL
Back in the day all the bikes I test rode at an interbike were mis tuned
the first year Reign had a Psylo that was puking oil big time
the exception was the Cannondale Prophet, Cannondale bro asked how much I weighed pumped up the suspension to the recs on the card and it rode awesume
Lee Lau - xxx-er is the laziest Asian canuck I know
A friend demoed a bike this summer, bars were fine (large frame so not a huge deal) and they set the suspension pressure to his rough weight which was good. We discovered the rear shock's rebound was set to full fast when the rear tire was like an ice skate on the first descent. Luckily between the two of us we have one semi-functioning brain and figured it out pretty quickly, but someone who's not very savvy might have ended up hating the bike or hurt.
When I was looking at shorter travel bikes a few years back I went to a demo event with 3-4 manufacturers. Tried out a Pivot Mach4 since a lot of people rave about it. It felt like absolute shit, the rear suspension seemed to make the rear end skip around. Would have been better if it had been a hardtail. I dropped the pressure a bunch of times and played with the rebound too. Dropping pressure helped some but this put it way below where it should have been. Never found out what was wrong with it, and didn't buy the bike.
This was the same day I went to take a Santa Cruz 5010 for a spin and the brakes were engaged against the rotors when the bike was just sitting there. The mechanic told me "oh yeah those SRAM brakes swell up sometimes when they're in the sun and the pistons press against the rotors". Um, you know where you are right - Socal where we ride bikes in the sun all day? He didn't seem to think this was a problem at all or unusual.
In his defense, that was definitely true. Never happened to me while riding, but on a few occasions I'd leave the bike sitting in the sun and they'd start to seize up. Moving the bike to the shade for a couple of minutes would resolve it.
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