In an event where race results are within fractions of a second, mechanics often really on unconventional practices to help reduce weight and increase speed.
In the clip below (starting at 4:38), Greg Minnaar’s mechanic, Jason Marsh, explains some of the tricks he uses to help lubricate the cranks and BB.
We probably wouldn’t recommend these techniques for your park rig, but every little bit helps on race day!
So dump the plastic seal/spacer because it’s too heavy, but to go back and add a healthy amount of ATF eliminates any weight savings. At least the ATF provides a lubrication benefit. Also, did he mean to say worn out or worn in? I’d love to see a blind test showing how much of an advantage these “secrets” actually make on the course. I think the real benefit comes from Jason poring over every detail.
@Ryan, if you are referring to Gwin’s chainless victory, I was just having a discussion about this with a friend. His take was that like Atherton’s 9 sec. gap at Windham, when you have nothing to loose, you let it all out. In Atherton’s case, she had already secured the championship before her run so she could take risks she normally wouldn’t. In Gwin’s case, he broke his chain, so it’s a free run to see how fast he could make it down without one.
Since they have a whole season to run, they have to hold back in the riskier areas which could end their season. This means in the less risky areas, they need to pedal their tails off. So multiple gears for the different sections that require pedaling. Maybe the TV doesn’t show it because it is “boring.”
Hahahahaha! Why not just get ceramic bearings? They generally ship without lubricant, and start to feel “worn out” in very short order.
I think the real reason SC Syndicate etc. has no hesitation about sharing this “pro tip” is because NO ONE will EVER gain ANY benefit AT ALL from such antics. Not so much an every-little-bit-helps thing as a profound psychosomatic soother.
@SB: you clearly haven’t used a proper ceramic BB or bearings before. Try out a CeramicSpeed if you get the chance. Yes, having smooth-running bearings makes a difference. Maybe not to the average rider who is out on their old clapped out ride, but for racers fighting for grams and microseconds – for sure.
+1@Boom.
To put it in another context, we have a wheel chair racer that has us go through his race chair with a fine-tooth comb. The main focus is on the bearings. He uses his own concoction for lube in the bearings and a precise amount. He’s made his own dust shields to protect the bearings since we’ve removed regular seals.
The time difference between his training wheelchair and his racing can be over a minute over 10k.
The racing chair is only used on test days and race days.
In every sport where machines are used at the “highest” level, teams will strategically take risks to increase their odds for a big ol’ W.
Anyone who thinks that ANY manipulation of the bottom bracket bearings on a racing bike could be worthwhile should look at how much power is lost in there. Worst case for BBs in good condition is a couple watts. Ceramic, oil instead of grease, “broken in”, it’s all completely meaningless. A simple search will turn up a competitor’s website with an article that tells you all you need to know about this folly.
Cool tip. I think the constant oil bath really makes a difference, for any rider and any use. Still, I think just installing a XTR crankset, instead of the heavy DH crankset, as they have done so many times and I bet they still might do, maybe not, but anyways, that reduces the weight quite a bit, it may help more that this BS of pre worning out the bearings.
All this banter about how little pedalling is in DH, shows you boys are slow pokes on DH bikes or never ridden downhill. Close ratio tight gearing is used pretty wild. These courses aren’t always straight down, they can be flat, some have upshots in them.
Minaar is one of the most pedal heavy riders out there. It’s neat, it could be psych ( I agree it’s useless), but hey it’s there deal. Gee Atherton runs no seals and dry in all of his bearings on race day.
I bet they don’t run ck bb because they’d rather swap them out before and after every race run… And ck presumably don’t do catering boxes of bb like shimano do!
Also the cynic in me says they run gears because they have gear sponsors, particularly given as many are now running shorter blocks
In the mid ninetees Cannondale/Magic Motorcycle had a prototype crankset with the bottom bracket completely filled with oil.
There even was a window to check the oil level.
And PMC made a BMX crankset with a sleeve bearing running with oil.
So oiled bottom brackets is not totally new.
By the way: The designs of all the Hollowtech/GXP etc. cups are a near 100 percent copy of the Magic Motorcycle BB cups from 1992. Even the tools are fitting. Just if you think that I am writing of stuff that is more than 20 years old.
On a full suspension bike the distance between crank and rear wheel changes as the suspension compresses. So you can’t run single speed without a spring loaded chain tensioner. So for that alone you should run geared because you will already be half way there. Also, they only showed about 5 seconds out of each rider’s the and a half minute run. They pedal plenty, especially at the START where if they don’t get up to speed fast they will lose a lot of time. So they need a range of gears for that and any mid course pedaling. Think people!
Unfortunately the Red Bull replay doesn’t show the entire track & there are places where racers can get some pedal strokes in. You all should check it out next time the circus (hopefully) hits town again…Ah, the luxury of living an hour away from Windham!
Oil filled BMX BB…hmmm, I think I could use that instead of my Profile double row bearing sealed one!
the one thing that stuck out to me was the statement that spinning the bearings unloaded at 350rpm for 5min brings them to nearly worn out condition.
..that’s 1750 revolutions unloaded = worn out.
even with the lubricant flushed out that’s ridiculous. Even rubbish bearings are waaay more resilient than that.
@Dan, I don’t have the actual names of models handy but I can tell you that the spread from best to worst in the test was about 2w total. Also, while the top model was ceramic and the bottom model steel, there were models of both materials in the top 5 with only about .1w separating them.
BikeRadar did a high level review of the testing that you can read here: http://www.bikeradar.com/us/road/gear/article/friction-facts-measuring-bottom-bracket-drag-39233/
Remember, Friction Facts also tested chain lubes and found nearly 6w between best and worst lubes.
@Kark, I know, right? Basically he said that those BBs are worn out after the equivalent of a single sub-1hr ride at 90rpm. All else being equal of course.
@Everyone saying you don’t pedal in DH
Stop sucking. Stop being slow. Lay off the brakes. And SPRINT into the gnar. If you think you don’t pedal your ass off in a DH race, maybe trying moving up from the beginner cat. Take last weekend’s race at MSA- Bruni smashed the tech sections but because he dropped a chain he ended up loosing 3-4 seconds in the bottom sprint, and it most definitely cost him the race.
@BT
“And one other thing, these DHers don’t do massive gaps and a pro roadie puts way more stress into a pair of cranks.”
AHAHAHAHHAHAHA!!! You’re delirious. Gaps- watch the track walk. Do those gaps look tiny to you? As for the roadie thing- look at a DH BB shell. Now look at a road bike BB shell. Now compare say, Dura Ace cranks to Saint cranks. Now compare power data for pro roadies (950W peak for most TDF stages) to power data for the EWS riders who share it (1950W peak for Jared Graves). Now realize on a mtb, pedaling forces are vastly dwarfed by the various drops, hucks, and rock gardens. Now hang your head in shame at how ridiculous your comment was. It’s not even true by a factor of three.
I’m going to echo the few and far between comments on pedaling. World Cup downhillers pedal significantly more than you would think. Hell, even your average Cat 1 regional guy pedals more in their race run than you would imagine. Having been at races where world cup pros have been, they find places to pedal that you never could have imagined. All while putting out way more power than you.
Hell, even Charlie Sponsel could beat all of you doubters in a sprint.
@wuffles (1950W peak for Jared Graves). Now realize on a mtb, pedaling forces are vastly dwarfed by the various drops, hucks, and rock gardens. Now hang your head in shame at how ridiculous your comment was. It’s not even true by a factor of three.
Jareds power output was tested on faulty AIS equipment back in 2000.
As for you other comments about cranks, have a think about the suspension that DHers use that takes the impact and then pedals.
@BT
False http://www.pinkbike.com/news/Jared-Graves-Rider-Journal-EWS-5-Whistler-2013.html
That’s on a Stages power meter in 2013.
You seem to also have a completely backwards understanding of suspension. There is minimal unsprung weight on a DH bike. The vast majority of mass, and hence force comes from the sprung side. The way this mass gets slowed and redirected in a controlled manner is through the cranks and BB and into the suspension. That is, both the BB and cranks see the force of an impact before the suspension does. Which is why DH cranks and BBs are built beefy as hell.
