Modern Vespa

I'm appealing to the wisdom and experience of the MV community to help
me understand what (may have) transpired during a mishap last week. I was
riding normally, ~30 MPH, on my 200GT when I hit a small wet patch (for
San Diego locals, SB on Pacific Highway where it passes under Barnett JNO
MCRD, a chronically wet and dark area; for nonlocals, this is about 1/2 mile
from Scooterwest). I felt the front end slip/slide a bit, and just as I was
registering 'uh-oh' a severe wobble started; after about 2-3 oscillations the
scooter dropped and I was sliding on the pavement.

My injuries are relatively minor, and my once pristine scooter has some ugly
scars, and my plans for AmeriVespa suddenly scuttled.

After I felt the slide, I don't think I did anything to exacerbate the loss of
control (ie, I don't think I braked nor accelerated/decelerated). The 2005
200GT is my first PTW; I've had it around 18 months and put about 4500 miles
on it, and have felt very comfortable on it since about the first month
(including riding in the rain). I've experienced the 'normal' GT deceleration
wobble and road groove tracking without consequence. I've completed the
MSF safety course and am a conservative and risk-averse driver. Scooterwest
has maintained the bike throughout it's lifetime.

When the Scooterwest crew returns from Flagstaff I'll have them check out the
bike (and re-set the handlebars), but I doubt they'll find any mechanical
smoking gun for the death wobble, since it had been running well with no hint
of instabliity until the crash.

So, my main question is: I don't understand how hitting a slick spot turned
so rapidly into such disasterous instablity. I'm an analytical kind of guy,
so without a theory of how slip => wobble => dump I'm now a bit spooked
about riding through puddles, over construction plates, or other possible
triggers of slippage (even though I've experienced all that in the past with no
ill results).

Any theories are welcome (including questioning my riding competence). TIA.

Tank slappers happen often when the front wheel loses traction and as the forward motion of the bike tries to catch up with the rear wheel, it's off balance. The common wisdom is to get your weight back on the rear of the bike, and lightly tap the rear brakes to get the rear wheel speed to match the front, all the while keeping a firm grip on the handlebars.

Sounds great, right? Maybe a slow speed tank slapper can be overcome, but anything at speed is just a blur. No time to think it through, and certainly no good ways to practice the maneuver.

Glad you're not too beat up.

Not much to say other than that sucks.

Are you assuming it's not rideable? Handlebars are often easy to align, and if the only other damage is cosmetic, you could do okay at AV. Maybe a good thing as other riders might keep their distance.

That small wet patch, what was it? Just plain water? Or could it have been something else, such as oil?

Good question.

This patch of road is difficult to examine, as it's not accessible by sidewalk and
is heavily traffic'ed with no shoulder. The roadway has terrible drainage and
always seems to be wet; a neighbor of mine speculated that there may be moss
growing there.

The bike is rideable (I nursed it home ~2 miles after the crash), but am not able
to align the bars (a recent MV thread has some good tips on that, but my
general feebleness is enhanced by the rotator cuff injury incurred). I also want it
reviewed by pros before undertaking the ride to Flagstaff (there's a lot of barren
desert between San Diego and there).

Good point about keeping distance, but that's not the kind of first impression I
wanted to make

I've realigned my handle bars by holding the front tire flat against a curb, and with both arms, yank the bar in the direction I want to correct.

Others stand in front of the scooter, grip the front mudguard between the knees and do the same move. I think taller, larger folks have better luck with this method. I'm not tall/big enough to make that happen.

I fully understand your worry. Something unexpected happened to you and you want to understand why. Otherwise it feels like random and that kills your confidence on the scooter.

It seems to me it could not have been plain water. There is no reason why if you go straight through a small spot of water that would bring the scooter out of balance.

Moss could be it. Part of your front wheel circumference picked up moss and lost grip leading to the instability.

Another question: you say that that particular piece of road is heavily trafficked.

Where do you ride within the lane? Left, right, in the middle?

How awful, DirkB. I'm glad you were able to ride home and tend to your wounds. That's preferable to hitching an ambulance ride to the hospital. I hope your scooter's damage turns out to be cosmetic.

I bet that was a patch of diesel (DIEsel) - slicker then ice. If you ever hit a patch, you're very lucky to stay upright even if you're riding straight. On a curve - you're off.

Between the small tires and short wheelbases on these Vespas, there isn't much room for error. I worked on a GTS300s recently and took it out for a test drive after all the work was done. I could not believe how much the front end osculated! It wasn't a white knuckle ride, but it wasn't all that smooth either. I checked the tire pressure, general condition of the tires, the fork bearings for slop before the ride and again afterward. The bike was put up for sale as the owner had moved on to another ride, so I suggested the the new owner to keep both hands on the bars at all times and think about getting a different brand of tires.

How many miles on the front tire? How's the tread?

EXACTLY! Random, indeed. Thank you for posing this question and prodding me to reflect on lane position. I generally ride in the center of the lane, unless traffic conditions motivate me to move to one side or another. I was probably in the middle when I slipped; I knew intellectually that the middle is the worst place for 4-wheeler drippings (and possible slimy biology), but now it literally hits home. I think this may be the take-home lesson from the experience: don't ride in the middle, especially when lane condition visibility is poor.

were you accelerating a bit at the time? if so that could possibly trigger what starreem is talking about.

as to reducing the likely hood, the were in your lane of course matters as mentioned but also the position of your hands on the handle bars. slightly having the heel of your hand behind the bar a bit more helps. this can make reaching the brake levers a little harder which is when adjustable brake levers can help. lastly all the usual things about reducing the wobble at lower speeds does help but there are many other threads on this and with several contributing factors (tire conditioned, pressure, bar end weights, suspension, bearings, ...)


PS, a small request (I hate asking this) can you please not manually format your posts as this looks like absolute crap on a phone as it becomes one line then two words then one line then two words then one line then two words and I just can't read this until later in the day when I'm a computer.

About 2200 miles.
Tread looks good; 20 Kmile service 800 miles ago indicated 75% remaining tire life both F & R. Front currently 25 PSI, rear 30 PSI

Thanks for your thoughts. Agreed.
Something went wrong between 'preview' and 'submit' (I think I hit some CRs) and botched the lines. I'm learning something every day! (Some lessons more painful than others).

thanks for understanding. (I really should have messaged you about this rather than a public request)

Although this is a good heads-up to the others that do this. You should know who you are...

Congrats on not dying and not coming close sounds like. Were you wearing gear and if so did it help?

I've gone down on a freeway onramp due to diesel on the road. I could easily see the same happening from moss or algae really due to no rider error other than maybe not being in one of the tire tracks which might help.

Best wishes on a full recovery for you and your machine.

Like others I suspect something besides plain water was in that wet patch. Sometimes there simply isn't anything you can do.

The only time my son has ever dropped his bike was similar, water in a pothole with wet leaves on the bottom. He knows about the wet leaves as they were stored up when he picked up the Buddy he was riding.

Another lesson learned; I was wearing denim jeans and a midweight, synthetic jacket, but only because the weather in SD has been so crappy (by SoCal standards). My clothing survived essentially unscathed, despite various small scrapes, a large abrasion on my knee, and banged-up shoulder.

I usually wear thin pants (or shorts!) and shudder to imagine the road rash I would have suffered had I been attired in my regular Cote d'Azur couture. Sturdy clothing is covered in the MSF safety course, but I arrogantly -can't happen to me!- chose to ignore that advice.

Thanks to you, and all respondents, for support and good wishes.

There is a fine line between being dressed to be comfortable and not being dressed enough for safety . I am glad to hear that a pair of denim jeans saved you from more serious injury. Hopefully there will be no future episodes of tires not staying road side down.

I expected you have the habit of driving in the middle of the lane. And that is not the best position and your reasoning why it is not is fully correct.

The best overall position in the lane is in the left track, that is where the left wheels of cars and trucks run. The risk on meeting debris or slippery things is lower and you have the best view on traffic in front of you and traffic coming from the opposite direction, and traffic from behind will not push you to the right in an attempt to overtake.
That is for straight roads and off course for right hand driving traffic.

This morning I rode my motorcycle up Big Tujunga Canyon, one of the nice twisty roads around here, and after you go over the top and partway down the other side there is a water crossing where a creek just plain crosses the road. It's usually not too bad and will most likely dry up completely by August, but a few months back it was impassable due to heavy rains. Today it was easy to cross but as it dries up to just a film on the road it can be treacherous, so much so that there's a warning sign, a version of which may have helped you:

DirkB,

As usual, great info provided by these Modern Vespa posters.
I am afraid there is no answer for unstable road conditions on
two wheels. You simply are going to go down.

Curves are the worst, even in dry conditions when there is
loose gravel or sand on the road.

To minimalize your risk, if it is raining ride straight and slow down
to a crawl when turning. In turns, look to the surface for loose
gravel and sand and avoid them or travers it slowly.

Whenever I was in a tough situation, I hit max throttle to allow
the gyroscopic nature of two wheels to right the scooter.
If the surface is grease lightening, you are shit out of luck

Ride well and safe - rookies take curves to fast.

Bob Copeland
Minnesota

🤦

I will also like to add - After a dry time, the oil on the road will rise up and start to wash off during a shower. If you are already riding, pull over when possible and chill for a bit. Give the rain time to wash the junk off the road, If you haven't started out yet, just wait awhile.

We got one of those, doesn't stay wet long enough to grow slime water (usually) but after it dries there is usually gravel to look out for.

SoCal is sunny and warm more days a year than not (not so much this year…yet) Same here on riding attire, Levi's or shorts and tees but always make my girls layer up, going to get some hot weather textile riding jackets and protective gear for them before it gets hot.
Anyone have suggestions on gear that is safe, cool and won't break the bank?

For warmer weather gear, check out the street and steel line that cycle gear carries. My husband LOVES the hoodie. It has the pads, same as his jacket but it breathes and looks like a regular hoodie.

I'm always cold - still wearing wool and long sleeves despite it being June - so I just use my regular jacket. At some point, I will remove the quilted liner and the waterproof liner, and swap my winter gloves for lighter ones - but that day isn't tomorrow. The weekend doesn't look good for it either![/quote]

Thanks.
Protective hoodies will be an easy fashion sell to my teenage girls, for some reason kids seem to wear hoodies when it's hot out (and beanies too) 😂