JanMM

This is a disc brake question, I guess. Took the Screamer on a moderately hilly (Southern IN) club ride yesterday and ended up riding in rain most of the ride. Which wasn't bad, considering it was warm and not stormy. But, of course the road was wet and I found it not hard to lock up the rear wheel with the BB7/203 brake. (V-brake on the front.) Had never experienced that before - we seldom ride in the wet. Told my stoker that she needs to put on some weight........which was received well.
After figuring out this braking issue early on in the ride, took it easy on wet downhills, especially if they weren't smooth, straight and with good visibility.

The question: Is this simply a matter of wet road surface making it easy to lock the wheel with a disc brake or is my adjustment suspect? Would the improved modulation of hydraulics lessen this issue compared to my mechanical set? I'm assuming the obvious solution to the issue is to just be cautious and keep the speed down appropriately when riding in the wet.

On a related note, because of the rain we lost control on a wet steel grid decking on a small bridge and went down onto our left sides. A little blood and some bruises but no broken bones or bike parts and we were able to ride 20 miles back to our car. Sore today.
Lots of these small steel decking bridges in rural Indiana - have ridden over them lots of times but not sure if I'd ever ridden over one in the wet before. Lesson learned.

twocicle

Sorry to hear you went down on the slippery. Luckily you sit close to the ground and not a big drop to impact.

Have you tried reducing your tire pressure by a couple psi for wet riding? A softer tire allows for more contact patch and therefore more traction.

Goldrush

Two of our local counties here in western Indiana have started using the steel grid bridge decks. These are extremely dangerous for cyclists when wet. Fountain county have placed signs warning of this (not cyclist specifc). They did so because of a crash and I believe law suit.

We often walk these bridges. I glad you escaped with minor injuries. If you face hits the decking it can be very serious.

JanMM

Yes, not as far to fall on most recumbents and sometimes the seat absorbs some of the impact.
Lower pressures might be of help in the wet and certainly if the wet surface is rough. We're riding on 1.5" tires so we have some leeway for dropping down a bit.

mibike

Sorry about your fall. I have BB7/203 on one of my tandems and bb7/200 on my triplet. I've never had a problem with locking up the brakes in the rain. I just got back from a 5 day ride with rain for 3 days on the tandem no problem. Rain is when I like the disks best. I also have a tandem with V-brakes and one with cantilever brakes. They all stop good when it's dry but the disks are a lot better wet. Had the rain just started? The road will be slipperier when it first starts raining until some of the oil etc. is washed off.

chris ss

Sorry here too to hear of your fall and glad it wasn't more serious.

The simple fact + physics of it, is water is an excellent lubricant, chemically speaking, in the short run. (It's not used more for lubrication, because over the longer term it has 2 big disadvantages- a) it evaporates easily/quickly, and b) being a polar molecule, it promotes corrosion more/faster than oil + other non-polar molecules.)

So yes you were right with the title of your post. There is just no technology which can restore the adhesion that you lose, when roads + tires are wet, which means you're gonna be better off if you just slow down when it's wet. This is just as true on a bike as it is in a car. What kind of brakes, 4-wheel drive + anti-lock brakes on cars, etc ... all these don't change things all that much, when water- a good lubricant- coats the road and the tire. And yes it's often worse when it first starts raining, cuz there's usually a light coating of oil on many roads, which is lifted up off the road and floats on top of the first rainwater, before more rain washes/rinses/carries it away in the runoff.

'nuf physics+chemistry - glad you're alright.

JanMM

Stoker tells me we'll be walking across steel grid bridges, whether wet or dry, at least for the time being.
We'll be continuing to make rainy rides the exception.

zonatandem

Glad they are not using steel grid on bridges out west (yet).
Have always been cautious crossing wet RR track also.
However, living in the desert, chances of riding in the rain are almost nil!
Glad there were no broken bones or gear!
Pedal on!
Rudy and Kay/zonatanmdem

LastKraftWagen

Thankfully the damage was minimal!

A few dumb questions since I've never seen a RANS (which is from what I gather is a recumbent)- Is the rear wheel smaller than a 700c? I wonder if a smaller rim diameter with the 203mm rotor has some effect on braking, and may be a bit of an overkill in the wet. Does a smaller rim diameter effectively apply less force to the disc, in other words, is the effect of a larger rotor on a smaller wheel a mechanical advantage for the brakes?

Not a solution, just a thought.

JanMM

Interesting thought. RANS Screamers have 20"/406 front and 26"/559 rear wheels. (Mine has V-brake front and disc rear brakes.) So, yes, that's smaller than a 700c/622. Not sure how that would effect relative braking effectiveness.

B. Carfree

There's one long-standing steel draw bridge over the Sacramento river at Rio Vista. Back in the '80s I rode over this nightmare regularly when riding between my parents' house in the Bay Area and my place in Davis. Thankfully, it was always dry when I went over it, but it still felt like riding on ice. My wife assures me it is even worse on a motorcycle.