All time personal best achieved tonight

Jim Gerwing

Well-Known Member
All time low

I crashed.
A combination of factors took me down: a three yard long, 3X3" gash in the pavement that I hadn't noticed on my first pass was the major contributor, speed(+40km/hr), reaction time, incorrect response (in retrospect, maybe I shouldn't have tried to get back on the pavement having been jolted off of it).
Injuries: sprained left pinky, sore left shoulder, skinned pinky, road rash on inside of left arm, deeper road rash on left trochanter about the size of a dessert plate, road rash on right gluteal(I can't figure out how that got there). Bones, head and neck not involved.
Bike: The left handle bar on the bike got pinched(saved from worse damage by my pinky, hooray) and, of course, the tape was torn and the bar end came off but I found it. I don't know yet how much the handle bar is bent. I had to ride the bike home and everything seemed to be working but I was not too concerned about a smoothly operating bike. The fairing on the left side was messed up but I have a new idea for improvements.
Consideration: as this project grows in complexity, I'll have to give serious thought to parameters like where and how this thing can be ridden with a fair shot at safety. Obviously, pushing limits (even personal limits) has a degree of danger. I realize and accept this.
It will probably be two weeks for healing and repair if all is as described above.
It could have been way worse.. . .
down but not out,
JG
 

Eric Winn

Zen MBB Master
Sorry to hear about the crash

Sorry to hear about the crash Jim but glad to hear you are mostly OK. Sounds like the Vendetta cockpit mostly protected you as you went down - that was my experience anyway.

The base of my right ring finger and pinky got gouged and scraped pretty good on my smackdown. In retrospect, I think I got "bitten" by the shift paddle under the brake lever of my brifters.

Stay safe. Good to hear you are not too discouraged.

-Eric
 

Jim Gerwing

Well-Known Member
Update

Well, I'm healing up. I've been on a stationary recumbent up at the local fitness centre for about two weeks.
It turned out that I had damaged the front rim beyond repair ( I had it trued but it had a bump in it) and because I slid on the left side of the bike, the rear brake was bent (Avid BB7 to be replaced with same).The left side of the handle bar got a crimp in it near the bar end - here I am going to try a set of clamp on aero bars with bar end shifters and Jtek aero brakes. If I can master the resulting configuration on rollers over the winter, I'll make some more essays into the esoteric world of aerodynamics.
This past season was a qualified success. Except for that one fall there is no way (in my advanced maturity)that I should be setting personal bests on a bike unless it was a pretty special bike (kudos here to the Cruzbike Vendetta)
On a side note: I did not suffer a single flat this year.
JG
 

Eric Winn

Zen MBB Master
Good to hear you are OK Jim.

Good to hear you are OK Jim. Let us know how you and the Vendetta work on rollers. I haven't bothered to try mine since I have a KICKR now.

When you get your handlebar setup I'd like to see photos and get a report on how well the Jtek brakes work. I really like the hand placement of John's bullhorns and although the cabling is a PITA to accomplish it is really comfortable not to have cable runs under the bar tape.

What is your assessment of having disc brakes on your Vendetta? I haven't been caught in anything but a short, light shower on mine so my rim brakes haven't been used in real wet conditions. They work great for dry stuff.

-Eric
 

Jim Gerwing

Well-Known Member
New personal record

Sorry I haven't been posting this season on this site (check out my Facebook page for more recent stuff). But I am pretty excited to announce a new personal best in a time trial type ride. I've changed my favorite road from last year. Anyway, 40 km in 52:14 for an average speed of 45.9km/hr. You've gotta see my newest aero innovation but my iPad does not play well with this site so, again, check out my FB page. And I've got Another great project on the go that surpasses last year's paper prototype.
45.9km/hr-I'm 55 and this is the fastest average speed I have ever achieved.
 

Eric Winn

Zen MBB Master
He's baaaaaccckkk!
Way to go


He's baaaaaccckkk!

Way to go Jim! I've seen your FB page, how much difference do the aero-feet make?

-Eric
 

Jim Gerwing

Well-Known Member
The difference

I have shaved two minutes off of my best 40k pace of last year. I'd like to calculate how many watts would be required to go from 44.3km/hr (average speed) to 45.9 factoring out the aero-booties.
But I have discovered a significant meteorological factor that I have never before taken into account (and I've never heard any cycling specific commentary on the subject, either; that is, air density.
I first got an inkling of this, this year. On my first TT with my front wheel 'storm-doored' I was expecting an improvement of about 45 seconds. I got over two minutes which was just too good to be true. So I said to myself, WTF? I've been doing some flying and one consideration of take off performance is density altitude. I made the connection with my cycling. I retrieved the barometric readings from a couple of my best performances and, lo, the density altitudes were high (or you could say air density was relatively low).
All this to say, yeah, I'm reaping some aerodynamic benefits from these mods (the body position afforded by the Vendetta being a significant factor) but the picture is complicated.
 

Charles.Plager

Recumbent Quant
Good online bike calculators

Good online bike calculators all take air density into account (some will even help you calculate it).
 

Jim Gerwing

Well-Known Member
On the night in question

I should add that, on the day of my latest PB, the density pressure was relatively high. The elevation of my route is about 2,500ft. I calculated the density pressure for that ride to be 3700ft. dP is, of course not the necessary nor the sufficient condition of peak performance but there it is. The down side of dP (or air density) as any pilot or mountain climber will tell you is the debilitating effects of 'thin air' on respiration at high altitudes.
 

Jim Gerwing

Well-Known Member
Raising the (personal) standard

On a near perfect evening (density altitude relatively high albeit the slight haze from distant forest fires), I set a new PB: 40k in 51:38 for an average speed of 46.5km/hr. Huzzah! Take a look at my FB page. The aero-booties are not shown in this pic and I made a slight mod to the tail box. Stay tuned for a radical departure from some of these tweaks I've been making.
 

Jim Gerwing

Well-Known Member
This sounds like a broken record

40k tonight in 51:17, average speed 46.8km/hr. Density altitude was this season's highest (4260'), slight push on the inbound leg.
I had no expectations of a PB, so I was very relaxed. I might even have a little more in this configuration (if the optimal atmospheric conditions visit again), because my index shifter is reluctant to give me my top gear on command.
 

KiwiGuy

Well-Known Member
Holy cow. Well done!

Hi Jim

Holy cow Jim. You've running super impressive times for the 40km time trial.

You might have some useful aero aids, but you're also doing a great job of tuning your motor.

Congratulations...
 

Jim Gerwing

Well-Known Member
250 watts

Thanks, Blair. I maintain that I can produce about 1/3 horsepower, which is okay but hardly Olympic. There are a lot of factors to consider in peak performance. And I am still looking for that Bob Beaman experience where everything comes together at once in an ecstatic moment. Swoosh!
 

KiwiGuy

Well-Known Member
Set-up comparisons

Hi Jim

Now that you've cracked a couple of PBs, and you're clearly in optimum shape, I'm wondering if you're in a mood to do a couple of comparison 40km TTs.

Specifically, it would be very interesting to find out:

#1. What time you can do on your Vendetta in stock standard condition.

#2. What time you can do on your Vendetta in s/s condition plus two low-cost aero aids - a rear wheel cover and a 'Quiver' style seat bag (like Maria used on RAAM).

Obviously your full aero set-up is going to trump either, but it would be particularly useful to know how close a s/s Vendetta with a rear wheel cover and 'Quiver' seat bag can come. Especially given that set-up would retain the 'chick magnet' characteristics of the Vendetta (to use your term
regular_smile.gif
)

Kind regards.... Blair
 

Jim Gerwing

Well-Known Member
Okay, but. . .

I don't think the comparisons are going to be absolutely fair with my season wearing on (environmental conditions are deteriorating). Although I'm not counting out the possibility of a few good days. Nevertheless for the sake of science, I will dedicate September to baselining.
 

KiwiGuy

Well-Known Member
Outstanding!!!

Fantastic that you're willing to try for baseline data.

Here deep in the southern hemisphere the days are getting longer thankfully, so understand the changing seasons for you.

As you say, the challenge will be encountering conditions roughly equivalent to your PB days.

I look forward to hearing how those runs go.

Kind regards....
 

Jim Gerwing

Well-Known Member
A partial report

In a nostalgic mood I set out tonight on my diamond framed bike, a Specialized Allez Expert. The bike is light and tight. Weather conditions not bad but not as benign as most of my Vendetta essays. Total km's-23, total time-37:17, avg spd-37km/hr. Maybe my technique was rusty and maybe the weather was a factor but my slowest rides on the V were faster than that.
 

Jim Gerwing

Well-Known Member
A 'quick' note

New PB, marginally. 40k in 51:07 for an average speed of 46.9km/hr.
Density altitude was about the same as my previous PB, 4225'.
one second faster and I would have been justified to round that off to an even 47.
My previous ride was on a DF; a very different feel to it.
I have promised some trials without the aero accoutrements, but I want that single second.
Zip-duh-dee-do-dah!
 

Jim Gerwing

Well-Known Member
Stand down

I took off the tail box and the aero-booties. Fairly nice conditions (15C and light winds mostly perpendicular to my route). 30km in 42:51 for an avg speed of 42km/hr.
 
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