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TheKaiser Added a comment about bike check Giant ATX 980 John Tomac "Downhill"

9/18/2024 2:33pm
Yeah, if I remember correctly, partway through the last season he rode this bike, he was blown away by how much better the Intense M1s were, and very shortly thereafter he joined the huge number of riders on M1s with their own sponsors paint/graphics affixed.
This bike check has 6 comments.
I think the other posts about the mirror like finish possibly indicating contamination are great advice, but I just wanted to add that, given that the pad-swept surface of your rotor goes right to the outer edge, and the rotor is relatively new to you, it would be good to double check that you don't have any pad overhanging the...
When you say: "Why is this a thing we must do?" do you mean: A. "Why do our very expensive brakes suck and require creative hacks to work?". or B. "Why does strapping the lever down help our brakes work better?" If you meant A, I can't tell you for sure, other than to say, either bike brake engineers lack...
If they are pumping up on rapid pulls but work consistently otherwise, as a general rule, it could be due to 2 different causes. 1. If the pumping up is taking you from an excessively long lever throw to a normal one, that is usually due to a poorly maintained brake that is low on fluid and/or has excessively worn...
Wait a tic, are you leaving the bleed cup overnight on the caliper or the lever? I'm guessing you meant lever, but said caliper, unless Mavens have a reversed procedure from most other brakes. Assuming that is the case, and you also have the levers rubber banded, it seems like it could be accomplishing 2 things. The lever compression could...
I totally agree with you regarding grip force being strongest when the fingers are closes to the palm, and have always preferred a bite point close to the grip as a result. I'm not so picky on free stroke as long as the return spring in the lever isn't so strong that it becomes fatiguing to hold the lever in...

TheKaiser Added a reply to Arm pump/hand pain solutions thread

6/2/2024 10:41am
Regarding your foot question, yes, had that problem too, in 2 situations. The first is when using either a flat pedal/shoe combo with insufficient grip, so I was reflexively trying to "grip" the pedals with my toes. Any of the top sticky rubber shoes and current big/grippy pedals would resolve it. The second was when using SPDs with shoes which...
No personal experience with the Dominions, but I have seen rare occasions with other brands of brakes where there was a bad batch of caliper seals, or a bad surface finish on a batch of pistons, which would keep the pistons from advancing properly, and causing excess sea rollback. The fact that you get a slight improvement with thicker pads...
That is an awesome thought experiment, and much credit to you for basing it on some potentially realistic numbers! Like you, I had assumed fluid stiffness was a trivially low component of the overall picture, and was mainly concerned with using a vacuum to help remove entrained micro-bubbles. If your numbers are even close to accurate, it does really give...

dberndt Liked a reply to forum topic Nerding out on Brakes shall we? Not another tech deraliment

5/22/2024 6:23pm
I find this all interesting, and I'm learning some stuff/doing more reading. So please correct me when I go off the rails here. Degassing should/could do two things. 1) Reduce the amount of entrained air that might appear in future (depending upon how well sealed the system is over long periods of time). This seems boring. Entrained gas follows Boyle's law and is very bad for brake feel/performance. It's what we should all be fighting, probably. 2) The more interesting discussion at the moment. Dissolved gases. These do not follow Boyle's law and do not have a big impact on...
This forum topic has 2968 replies.

Slavid666 Liked a reply to forum topic Nerding out on Brakes shall we? Not another tech deraliment

5/22/2024 6:23pm
Glycol ether (primary component of dot 4 and 5.1 brake fluid) contains approximately 19% dissolved atmosphere at STP. Most liquids contain some percentage of dissolved atm with alcohols typically containing more. Short of sparging with helium, vacuum degassing is the most effective method of dissolved gas removal. The soda bottle is somewhat different because it is supersaturated with co2 as a method of generating fizzy bubbles. Yes as the pressure is released the gas content decreases but once it’s done or reached is pressure equilibrium there is still 10 percent dissolved atmosphere in the liquid (approx, just guessing on this)...
This forum topic has 2968 replies.
Do you know what the transparent portion of the bars are for the Bionol and Gold oil on the left side of the comparison chart? Its similar to the way that Radic displays a wet/dry temp for DOT 5.1 on the right, but moisture shouldn't really be a factor for the oils. I'd thought it might have something to do...
The lowest numbers I typically see for mineral oils, just from browsing around, are around 150 Celsius for a flash point, and in the high 200s Celsius for a boiling point, so that Putoline must have some particularly volatile components added to have such a low flash (87) and perhaps boiling (some undetermined number north of 180). Not saying that...
How do you go about degassing it? Are you just talking about pulling a quick vacuum in a high quality syringe, or do you have some other apparatus and do it for longer? I have heard surprising claims about the amount of dissolved air contained in mineral oil (not sure if this would apply to DOT fluid too) and have...
That is an interesting take on things. I have heard that there is a surprising amount of dissolved air in mineral oil, right out of the bottle, so it makes sense that one could dissolve more into it if kept under pressure, and the bubbles (assuming a decent bleed in the first place) would be such a trivial amount that...
Are you saying that the flexed piston seals, which would normally roll back the pistons when the lever is released after a short pull, will slowly creep back along the piston under a long sustained pull as is done by strapping the lever down for an extended period? So it is kind of like advancing the pistons by squeezing the...
I have heard that rational before regarding keeping the system pressurized helping rid it of bubbles, and I just don't get how that would be helpful. In my experience, the opposite is what you want, as with a vacuum bleed the bubbles expand hugely and therefore have greater buoyancy. Going up/down in pressure rapidly could maybe help, as can vibrating...
Thank you for posting that master cylinder bore info! Companies frequently publish and even tout their caliper piston sizes as a feature but I haven't ever seen the equivalent for master cylinders leaving a big "?" when it comes to determining actual hydraulic leverage.
Wow man, I've just been catching up on this thread, great work on your fork! From the vids the newest revision looks to be working beautifully. I remember the twin shock Cannondale DH bike that had a similar "travel envelope" that was measured in square inches rather than linear inches, and it always seemed like a neat idea even if...