I know we have lots of bikers here on the forum and at the risk of preaching to the choir, I wanted to give a heads up to those you who may be planning an Upper Peninsula visit this summer via I-75 and the Mackinac Bridge. A good portion of the bridge deck is metal grating and if you have not ridden on grating before, when you hit it there is a feeling of loss of control and the bike tends to wander. This can be pretty scary, especially if its windy on the bridge. Its best just to relax and make small corrections to address the wandering. My bike weighs 500 pounds and this happens to me every time I ride the bridge but I am prepared for it and just putt on. Those of you on heavier baggers or cruisers may experience this a little less than I do. A couple of days ago there was a motorcycle fatality on the bridge when a dude riding a trike crossed the raised divider and struck an oncoming truck. No cause has been given for the crash but I cant help but think the guy was on the grating, felt the wander and overcorrected. But thats just a guess on my part. Be careful on the Mac! Be safe and come up and ride the Yoop!
Oh... Some downstaters were road raging and a shot was fired and that shut down the bridge too.
Bridge website: www.mackinacbridge.org

They do that because it allows wind to flow through the bridge so it doesn't push the bridge around and cause it to sway. Otherwise this might happen:

quote:

Its best just to relax and make small corrections to address the wandering.

My first time on a grate bridge (different bridge, somewhere in BC, Canada) was pretty scary at first, but I adjusted quickly.

I have read that there are people at the Mackinac Bridge whose job it is to drive or ferry peoples' vehicles across. That must be interesting.

I hate driving that bridge in a car...can't imagine doing it on a bike. I did it with our 12 foot box trailer once, and didn't like that at all. The worst part is that it's the middle lanes that have the grating...so you have a choice of either driving on the sketchy tire-grabbing crap, or right next to the edge !

I'll assume motorcycles react to things like grating and road grooving based on many design features and tires could be big factor. I was riding once on a road that had been ground down for resurfacing with another motorcycle. The grooving had minimal effect on my bike, but the other motorcycle appeared to be greatly effected by his response. He appeared to be nearly unable to control his bike and slowed drastically.

I would assume that the effect of gratings or road grooving on various motorcycles. ranges from slight to nearly uncontrollable.

I'm well aware. Try riding it in the rain sometime on a bike!

Even in a car it can be sketchy. It's the only bridge I am aware of that offers (or at least they used to) a service to have someone drive your car over it for it.

quote:

Originally posted by pbslinger:

I would assume that the effect of gratings or road grooving on various motorcycles. ranges from slight to nearly uncontrollable.

Tire construction has a big effect on this, as does steering geometry. If you really want to pucker your butt, drive over wet bridge grating on a bike with bias ply tires.

quote:

Originally posted by bigwagon:
It's the only bridge I am aware of that offers (or at least they used to) a service to have someone drive your car over it for it.

The Chesapeake Bay bridge on US 50 in MD has a "pull over here for escort/driver service" area just before the bridge entrance, I have seen cars waiting there from time-to-time. CUriously, it seems most of the cars requiring a substitute driver are large sedans, Mercedes, Cadillacs and the like, or maybe they're the only ones whose drivers can afford it? The Bay bridge too has section where the roadway is expanded metal mesh, and, yes, it does give a funny feeling to the driving experience.

I love riding on the Mac bridge, although probably not in a storm, at night.
Growing up there was a major bridge crossing a lake that was steel grate which I crossed all the time. Once you get used to each end of the bike moving left and right on their own it's actually fun. The most fun is on a dirt bike with knobby tires!

Wife and I rode that a few years back on our H-D bagger…right before we got on the bridge she tapped on the comms and said, “I’m not going to talk now…” and was quiet all the way across. We got stuck behind a semi and that added to the excitement!

When we got to the other side, she clicked back on and complimented me. Only other time I had to be that focused with her on the back was during a torrential rainstorm on the interstate in Milwaukee during rush hour. Yowza!!!

The accident was the hot topic at the NAPA auto parts store in Cheboygan yesterday. The man was from Cheboygan. I believe this is his: Obituary. Seems like he was an experienced motorcyclist and living in Cheboygan, I’d guess it wasn’t his first time traversing the Mackinaw Bridge.

We had a bridge across the head of Frenchman Bay that was open grate. It was built in the 20's for 20's sized vehicles. REAL fun meeting an 18-wheeler coming the other way. TWO semis was even more fun, swapping mirrors was a pretty regular thing.

I got used to letting the bike do it's own thing as that was the only way to get to town from here. (Still is, but the new bridge is paved...)

We had a mutt we called Gatorbait. He was the most laid back dog I've ever had. NOTHING bothered Gator.

Except that bridge. When the tires started singing on the grating, he'd dive for the floor and shake like a leaf until we were off that bridge.

Wife and I rode a 78 Suzuki GS400 across the Golden Gate, figured it wouldn't be that big of a deal after crossing it many times in a car.

Wind had the rear end moving around, it was quite the handful getting over to Sausalito... After we got across the worst part was thinking we had to go back...

Light bikes, big bridges, wind, lots of excitement

I
Have been over the Mac and it is a little different for sure. The bridge of the Yukon is steel grate and long as hell. I came over it in a heavy drizzle and it was nerve wracking.

Riding a cycle over grate is interesting. The first time it seems like you're about to lose control, but it but never strays too far. Back in the day my Norton felt like the front and back wheels were always oscillating in the opposite directions.

Fortunately I had experienced shorter sections of grate before traversing Big Mac, so it didn't completely freak me out. We'll be going to the UP in September in a 4Runner with kayaks up top. It has a nearly 9' profile with the boats, so crosswinds will most likely be our greatest concern.

The Hawthorne Bridge in PDX is a 1910 era vertical lift truss design with the fabulous grating I had never encountered prior to my introduction there in the early 70s.

On a motorcycle.
In the rain.

It was an event I don't care to repeat.

Although eventually I discovered it was possible to ride mostly ON the 4" concrete 'rail' that ran the length of the thing.

Over the years I did perhaps several hundred motorcycle crossings, usually unintended, but never grew comfortable with the sensation.

I’ve ridden a metal grate bridge in CT on the Merit Parkway near Stratford/Milford and it is an unusual feeling on a motorcycle. We also have an highway around Nashville that was grooved (440) that gave the exact same feeling as a metal bridge. It’s unusual to experience it and you just have to relax and let it do its thing, but I still avoided it when possible.

Did it once on a bike trip with a buddy coming down from Escanaba, MI......I had to look straight ahead the entire time...seemed like a week to cross it.

Merit Parkway is a beautiful scenic bike road.

I rode the Mackinaw bridge on my KLR650 on knobby tires during a rather nasty thunderstorm returning from a road trip. Of course, the pavement was closed, so this crossing was on the grating.

Between the wind gusts and the knobby tires wandering around on the grating, the bike was moving about a foot back and forth.

Just had to relax, be easy on the control inputs, and let the bike pick its path. It's definitely not the most comforting feeling, though.