Modern Vespa

Going west this am was a piece of cake, even on rain grooves, but going home heading east, there was a very strong cross-wind, which added to the stress and excitement of riding on the rain grooves even more so. Can't say that was fun.

It's weird, I feel the wobble on the lower deck going east, but not the upper deck going west. Is it wind, vibration, tide rolling in? WTF?

Not sure the 1 oz added wt with HVMP bar ends will help, but I hope so.

Add some bad drivers in there and you've got one of my least favorite bridges to ride or drive on.

Most of my motorcycle friends have gone down on that bridge. Usually hit by a stupid driver.

What tires are you running? They seem to be the biggest factor affecting wobble, especially on rain grooves. Heavier bar ends will help slightly with general wobble, but they won't do anything to reduce the "dancing" when riding over rain grooves.

I keep hearing about your 'rain-grooves'. How TF are longitudinal grooves in the road meant to help rain drainage? Shirley they should be across the road, to the side. Then no problem to any transport choice.

K61s (140 on back, 130 on front). They helped tremendously over Savas, but still feel wobble- only on grooves (on lower deck) + wind. I'd probably would have been okay without the wind, but there is often wind over the bay.

Jim- yeah, I have NO idea how rain grooves help the rain drain off on LOWER deck.

If you get the normal heidenau sizes (120 front, 130 rear), those rain grooves end badly. Both have the center groove in them, and track in those grooves.

Even worse, my wheels are ever so slightly off laterally, so each tire wants to track on a different groove.

D'oh.

Jim, I agree that grooves oriented across the road would make far more sense from the standpoint of actually draining away water and minimizing negative tracking effects on PTWs. However, they would be much more costly to machine into the pavement (no real defense as far as I am concerned), if you've ever seen how they do it.

They seem not to be intended to actually drain water away, but to create deep enough surface texture to prevent hydroplaning unless there is a real deluge.

"To prevent hydroplaning" - on wide flat car tyres then.

About time you guys got PTWs included in "Transport policy" if there is such a thing.

They love those grooves in California. Safe enough, albeit gut-wrenching to singletrack with narrow tires. Used to ride them on a '68 Honda 305. Hated it.

the K61s are night and day from Savas on the rain grooves and elsewhere. Simple physics with small bike and wheel on the rain grooves that make it feel like ice skating.

I rode across the Bay bridge on my return from AmeriVespa on stock Perrelli tires and really did not notice them ( rain grooves). There was some wind, but not bad

I've never once ridden a pair of Savas in the rain, or on rain grooves. I am really not a fan of them, for what I've ridden.

The Heidenaus, I love. My main set-up is a 130 front, 140 rear, the "right" way

Pirellis, Contis, or Heidenaus. Though, mostly Heidenaus

I dunno.... I've ridden across the bridge quite a few times on my previous Lambretta and now on my Vespa, both with crappy tires and at times with pretty gnarly cross winds- never had a problem.
I think the most important part is to not psych yourself out and just go for it.
Oh- and stay loose and watch out for crazy cagers...that parts important also.

I'll be riding across the Bay Bridge this Thursday and again next week on my way home.  I'll know now to proceed with care.

thanks, it was about my 15th bridge crossing today. I think the wind was the biggest part, which may have caused wobble. I had a loose grip, relaxed posture, but still no fun due to the wobble.

I've gone for it over the yrs- logged about 20k miles around the country on my bicycle, including going downhill at 50 mph, or greater on major mountains, while sharing the road with big rigs and logging trucks.

I hear ya.. I don't like riding over the bridge anymore than you. Sounds like you're doing it right though.
Keep it up

ment to reduce tire noise and add traction

please dont call me Shirley surely you jest

Give me the golden gate over the bay bridge any day.

I rode over the Bay Bridge after Rage to catch an A's game, going to Oaktown on the lower road, freaked me out, I kept thinking the bottom was going to drop out, I had to relax and breath and man up. Didnt notice the rain grooves.

Now coming back at night was a totally diff story, Cipote told me how bad the winds get when you get to Treasure Island. When I got to the toll booth I was freaking myself out, so I figured Id not go too fast and stay with traffic, funking traffic left me behind, good thing no wind, forced myself to breath and just rode it smoothly across but I have to say that was the longest ride ever.

Zippy on the front & Bridgestone Hoop on the rear. No problem with grooves either direction.

Ride Safe

Manny

I've heard it called tramlining. We don't have the grooved road surface here (except in road resurfacing), but I've experienced it on your side of the border. I can't see bar ends helping because it's caused by the wheels following the grooves as if they were railroad tracks.

It seems the way to handle it is to loosen up and let the scoot follow the rain grooves, but I'm really glad I don't have to cope with it like you folks do. The first time I felt it I thought I was going to be dead soon. That squirrelly feeling is something to hate ; I can't imagine dealing with it on a daily basis.

cheers

Hmm, here in New England it rains about 100 days a year. No "rain grooves" anywhere.

I'm sure our friends on the British Isles and northern Europe have it even worse (I don't remember seeing the sun in Germany, ever). I don't remember "rain grooves" there either.

WTF--whose bright idea are they, do they work? If so, what do they do, exactly?

Just asking.

Every time you talk about the San Fran bay bridge, I think about the big earthquake, when it opened up......Went over it in the 70's.....no biggie..
Now, if you want wind, ice, snow, grates, and a little swaying, go over the Big Mac in the winter! Now that's an experience!
They close it up to Motorcycles and High Profile Vehicles during high winds...
Lost a Yugo off there once!

er, that's alright.

Being flung off a bridge with a Yugo is pretty low on my list of ways I'd like to die.

Absolutely! Not the death part, the part where the newspaper prints your name and lets everybody know you owned a freakin' Yugo.

P.

Totally, it's like I always say. I'd never be caught dead in a Yugo.

This would go directly against that life credo.

My ride to work this am across bridge was fine, no problems and no wobble. It was great zipping past all the backed up cars at the toll plaza (on fly over car pool lane for free). However, it is short lived as there is talk about charging carpools and MCs a $3 toll starting in Jan. 2010- users must have Fast Trak.

So much for incentivising trip and fuel-use reduction. 

How's the San Mateo bridge as opposed to Bay bridge?

That's the ridiculous part of it. I'm also from New England and have dealt with torrential rain on a regular basis. I'd never encountered rain grooves outside of southern California where there is perhaps a gentle shower 10 times per year. Overall the quality of SoCal interstates is horrible.

Check your tire pressure. If you are running across rain grooves on a daily basis, bump the pressure up a few pounds front and rear from the factory recommended, which IMO is retardedly low. Does the trick for my P and my S.

never done it, but I imagine there is way more wind, don't know about rain grooves. I've drive across all the time, and it's a very long bridge, say around 7 or 8 miles vs. the 4.5 miles for Bay bridge.

thanks, will do that tonight.

they are all over Northern California as well. It rains a lot here. And it's pretty bad rain.