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Can anyone tell me why my MTB back wheel keeps locking up? It's the brakes, and I took it in summer before last to have them done, I want to do it myself this time but would like to know why this keeps happening...
#AskGMBNTech Is there much of a difference between downhill bike and trail/enduro bike sizes? I have a Polygon Siskiu in a small and a Specialized Demo in S2 (small), the polygon fits me perfectly but the demo feels like way too much bike on the trail even though they're the same size, are dh bikes naturally bigger or did I get the wrong size bike lol?
Ooo the LTS. I had a '92 team issue LTS-3 until it developed cracks in the aluminum. Now I have a (fully functional) thermoplastic carbon GT LTS, again team issue. It's beautiful.
Now you have explained who you are could you move on to what you stand for and your core beliefs around the conflict??? Utter nonsense, narcissistic gaslighting, hollow rhetoric. 😚🍒
When talking about both levers and calipers you didn't explain why does it matter, which is the hydraulic equation: F1D1 = F2D2. It literally tells us that the force applied on the one end, multiplied by the distance is equal to the force on the other end by it's distance. So oyou can move the large pistons at the caliper with huge force, but small distance, by applying small force for the larger distance with small pistons at the levers (and even increasing it with the leverage ratio of the levers themselves). You haven't explained also how do floating rotors help with heat management. And it's kind of advanced management at trhis point as it is not designed to dissipate heat better or anything like this. The floating rotors role is to isolate the hot rotor surface from the colder spider. As metals increase their volume when heated, the rotors want to expand. But the cold spiders prevents them from it, so traditional rotors warp when they are heated. Floating rotors allow them to expand equally on their circumference to prevent warping. As for the difference betwen pad matrial, the main one that you have not mentioned is their characteristics with heat. Resin pads work very well when cold, but fade quicker when heated. So they are good for someone who doesn't go on long downhills, but wants sharp brakes available instantly. Metallic pads do not offer full power when cold, but will work really well on long descends as they will not fade as quickly. I also dubt the part about adding the brake pad material to the rotors. Such thing could happen, but to do so, you would have to spin the wheel around 10 000 RPM to generate enough heat to achieve that.
Undo every spoke on your back wheel by 1 turn and you'll soon learn what the difference is. Plus it's easy to put back, just be sure the nipple is turning and not the spoke.
#ASKGMBNTECH Love the video. Just built my first bike from scratch from just a Trek frame. It was a very satisfying learning experience. But my question is as I want to build another bike from components leftover. I am really in between sizes so opted for a small frame as for the trails with drops etc felt like it would give me more confidence. But now scanning the 2nd hand market for frames should I be going for a medium sized frame as there seems more medium frame choices for creating a MTB/road invention with rigid fork as I am really in-between sizes. Thanks guys
120-120 is enough for most occasional bikepark riders in the flatter countries. Don't waste money and weight (and materials) for (on 🍟) stuff you don't need. I. e. don't buy a bulldozer when all you need is a shovel and a medium sized, 10 liter/litre 🍟 bucket :) Get better brakes and better wheels & tires (tyres 🍟) first.
Loving the Mezcals at the moment. Have mostly just run maxxis on my various bikes but have been quite surprised trying these. Love how well they hook up in turns.
#askgmbntech I have an older Specialised S-works M5 hardtail. 26” wheels on Hope pro 2 hubs. Can I upgrade it to 27.5” wheels. Would I need different hubs or could I use my existing Hopes? Do you think there’d be issues with chainstay length. Im running Nuke Proof carbon forks, would I need to update the forks as well?
Hi Dan, Great question - we'll definitely have to have a think about that one - watch this space for an answer on a forthcoming Ask Tech show! Cheers Owen
I read that Shimano rotors are 1.8mm. This is not so on the ones I use. (SM-RT64) They are 1.72mm. Meaning I have just 2.2mm useable thickness. Living in Devon means they don’t last too long.
I’m 5’11 with a very long torso and arms. On a large it feels like when I’m standing up I’m spending most of my energy not trying to catapult over the handle bars. So now I went with an XL
@@OwenBikeNerd Owen you have big shoes to fill after Doddy left. You’re not half bad. These style of videos I click on for the thumbnail idea and then it’s a completely random topic and talking head video at a desk. I know your just a bank teller of the bigger company, but this style sucks
@@BryenWilliams First up - in comparison to Doddy - as I'm still newer on the channel - I'll take "not half bad" - thank you! In regards to the constructive feedback again its always welcome - as you've been watching awhile - I know you'll know that with these Ask Tech videos we aim to answer questions pitched in across from all the off-road channels - so they're real questions. The thumbnail has a lot to do - yes its got to flag what we're covering in the show but its also got to have a slightly broader appeal to try and reach more mountain bikers and pull them into all the great stuff that we're hopefully doing on the channel. Having Anna balance on the wrongs sized bike might not work for you - but hopefully - flags to other folks that a question we're going to answer about sizing - which again I know you'll know is an important and deep topic to cover. Again great to have construction feedback - I'll keep reading the comments and feedback and keep trying to make up that other half on Doddy. Cheers Owen
For the leaky caliper guy - if it’s already out of warranty then it’s already out of warranty. If the pistons are leaking it’s irreparable without voiding warranty as Shimano don’t sell new pistons or piston seals Use whichever mineral oil you have or mix them .. remember you need to use a Magura hose and a Shimano barb and olive. Depending on which version of deore you have (age) it may be BH90 or BH59 Barb/olive
@@stephenlord599 yes, as long as the flow ratio from the master cylinder is close to correct for the new calliper (as Anna mentioned), it ought to work...
Mineral oil is graded on how distilled they are, which is dependant on the contaminants are in the oil. So there will be slight differences in how the oils react under pressure and heat, it's best to stick to what each company recommends 🤙
A couple of constructive remarks: 0. A system that absorbs a certain amount of mechanical energy has two fundamental choices: It can either release that energy entirely or it can dissipate part of that energy. The "thing" that makes your body/hands hurt less during downhill runs is the damping in the system (the ability of the system to dissipate mechanical energy), and not the ability of the system to simply absorb the energy. Damping in a bike is achieved primarily through the damping system (front, rear, ...), and secondarily through hysteresis in the tyre, spokes, frame ... A system can be indeed simultaneously stiff and compliant. The compliance of a system is defined as the inverse of the stiffness of the system... 1. The wheels are not generally squished from top to bottom, rather from the axle to bottom. The rest of the wheel follows due to spoke tension. The animation is misleading. 2. Talking about spoke tension, I appreciate that you mentioned the spoke length as an influencing factor for the stiffness, however I think lacing patterns could be also addressed in the context. Perhaps followed by a short talk about the bracing angle. 3. The lateral deformation occurs also mainly between the hub and the contact point. The rest of the wheel follows the imposed deformation.
Clean your chain once every month and just use a little motor oil and wipe off the excess. If you want to get fancy, get GT85 or 1-step. Use it to clean your chain and it lubes it just fine. Both these methods are super cheap and work just fine
#askgmbntech Hi Anna!! Talking about your video about wheels compliance. Starting from already knowing to true wheels. Would be safe or reasonable to play with spoke tension so you can get more compliance or stiffness on your wheelset? Nothing crazy obviously
On ergonomics and bike fit: Do you have to care about seat tube angle? Except for riding back uphill to do another run, I am NEVER on my seat. Also, the seat position is wholly adjustable, so really, why care when I can just move the seat? =) Thanks! #AskGMBNTech
For most rides I spend like half an hour riding up and 5 mins down so I'm on the seat the vast majority of rides. Tbh, I don't think iv ever seen a trail ride where people are standing more than sitting unless you are running shuttles.
within the same frame size, handlebar fit also makes a huge difference. with good fitting bars I can lap bike park top to bottom nonstop, with bad ones I had to stop after each section of trail because my lower back hurt so bad. played around with handlebar width and rise and got rid of riding pains. I needed something that put me more upright
