25.25 mi is 40.64 km
--Doug Sears
----- Original Message -----
From: "GEORGE SCHRECK"
To: ;
Sent: Monday, August 07, 2006 3:56 PM
Subject: Re: [OBRA Chat] TT Championships distance
My GPS which is very accurate, said the course was 25.25 miles long.
Since a 40k is 24.8 miles, it means that we went .45 miles longer than
a 40K. Rounded up, approximately 1k which is .62 miles.
"The other trick is to smear a dap of vasoline, toothpaste (ie
"something or other" that doesn't dry quickly) on the tire."
A moist raisin works well and it's easy to clean off - let
the dog lick it.
But have you ever tried to bomb people with surveying
marks?
Rick
One fairly accurate way to set your bicycle computer is to roll
out the wheel alongside a tape, as mike mentions... If you have long
tape, going two or three revolutions will help decrease measurement
errors. I also put the front tire to pressure and put weight on it to
simulate what it looks like when i am riding. The other trick is to
smear a dap of vasoline, toothpaste (ie "something or other" that
doesn't dry quickly) on the tire. It will leave marks on the pavement
a couple times as you roll the wheel (with weight and beside the tape
measure). You can literally measure to the nearest 1/8" or better,
from a feature of the 'mark' to the same feature of other mark(s).
Well I had a friend too who had like a hundred foot tape measure
and rolled it out beside that. He marked his tire with a marker first,
i think. (the closer the mark is to the ground the better.. so you can
see when it istop dead bottom. )
Another thing the same guy did was ride around a running track.
and then adjust his computer and keep riding til it was dead on. of
course who knows how accurate the running track was initially laid out
?
And finally the last thing this same guy did was ride roads that
were laid out one mile square. I was like "is that accurate?". He was
like yep dead on, surveyors usually are very very accurate. I would
question where exactly to begin or end the measuring.. ie where exactly
are the surveyors marks but i guess if you are off a couple of feet
every 5280', its not too bad? This was midwest too where the roads
were flat and perfectly straight.
I would think the most accurate way would be to find some actual
surverying marks and ride in between them. then adjust your
computer.. I know Portland has got a lot of Benchmarks at this site.
Of course you would need a computer that actually had
circumference adjustablitly to the nearest mm or so..
Ok I am not saying being this anal would be all too practical
for your everyday riding bike, where tire pressures change, wheels
change, etc, but maybe for your time trial bike or at least for a bike
or wheel that is used to set up the TT course.
I suppose GPS is getting pretty accurate too ? but i don't think
it can touch surveying marks.
The
Peoria TT course has not been 25 miles since well before Candi and I
were putting it on, which was at least 15 years ago. I don't know how
they
are determining the course length now but back when we ran it I
measured the
course several times with a measurement wheel applying a correction for
wear
on the wheel compared to measurement against a steel tape. I rolled the
course out by skating with the measurement wheel and I placed a maker
nail
in the pavement every 1K. We used to go out and locate those marker
nails
and then spray paint mark the road and also place a cone with a distance
sign every 1K. Unfortunately a few later the road was repaved and most
of
the marker nails were covered up. The county also got bothered by the
paint
markers and prohibited them in later permits.
Mike Murray
-----Original Message-----
From: obra-bounces@list.obra.org [mailto:obra-bounces@list.obra.org] On
Behalf Of Doug Sears
Sent: Sunday, August 06, 2006 21:51 PM
To: obra@list.obra.org
Subject: Re: [OBRA Chat] TT Championships distance
Thanks for fessing up so graciously. We'd all like to deduct 80 seconds
from
our times, but I have a hard time believing the course was a full 41 km,
since 25 mi is only 40.23 km, and the turnaround fell short of my
memory of
where the old 25 mi turnaround was. At any rate, it couldn't have been
more
than a hair longer than the old 25 mi course without running into
Harrisburg. So, how is the course measured, anyway?
--Doug Sears
_______________________________________________
OBRA mailing list
obra@list.obra.org
http://list.obra.org/mailman/listinfo/obra
Unsubscribe: obra-unsubscribe@list.obra.org
_______________________________________________
OBRA mailing list
obra@list.obra.org
http://list.obra.org/mailman/listinfo/obra
Unsubscribe: obra-unsubscribe@list.obra.org
One fairly accurate way to set your bicycle computer is to roll out the wheel alongside a tape, as mike mentions... If you have long tape, going two or three revolutions will help decrease measurement errors. I also put the front tire to pressure and put weight on it to simulate what it looks like when i am riding. The other trick is to smear a dap of vasoline, toothpaste (ie "something or other" that doesn't dry quickly) on the tire. It will leave marks on the pavement a couple times as you roll the wheel (with weight and beside the tape measure). You can literally measure to the nearest 1/8" or better, from a feature of the 'mark' to the same feature of other mark(s).
Well I had a friend too who had like a hundred foot tape measure and rolled it out beside that. He marked his tire with a marker first, i think. (the closer the mark is to the ground the better.. so you can see when it istop dead bottom. )
Another thing the same guy did was ride around a running track. and then adjust his computer and keep riding til it was dead on. of course who knows how accurate the running track was initially laid out ?
And finally the last thing this same guy did was ride roads that were laid out one mile square. I was like "is that accurate?". He was like yep dead on, surveyors usually are very very accurate. I would question where exactly to begin or end the measuring.. ie where exactly are the surveyors marks but i guess if you are off a couple of feet every 5280', its not too bad? This was midwest too where the roads were flat and perfectly straight.
I would think the most accurate way would be to find some actual surverying marks and ride in between them. then adjust your computer.. I know Portland has got a lot of Benchmarks at this site.
http://www.portlandtransportation.org/survey/searchbenchmarks.htm
Of course you would need a computer that actually had circumference adjustablitly to the nearest mm or so..
Ok I am not saying being this anal would be all too practical for your everyday riding bike, where tire pressures change, wheels change, etc, but maybe for your time trial bike or at least for a bike or wheel that is used to set up the TT course.
I suppose GPS is getting pretty accurate too ? but i don't think it can touch surveying marks.
Mike Murray wrote:
The Peoria TT course has not been 25 miles since well before Candi and I
were putting it on, which was at least 15 years ago. I don't know how they
are determining the course length now but back when we ran it I measured the
course several times with a measurement wheel applying a correction for wear
on the wheel compared to measurement against a steel tape. I rolled the
course out by skating with the measurement wheel and I placed a maker nail
in the pavement every 1K. We used to go out and locate those marker nails
and then spray paint mark the road and also place a cone with a distance
sign every 1K. Unfortunately a few later the road was repaved and most of
the marker nails were covered up. The county also got bothered by the paint
markers and prohibited them in later permits.
Mike Murray
-----Original Message-----
From: obra-bounces@list.obra.org [mailto:obra-bounces@list.obra.org] On
Behalf Of Doug Sears
Sent: Sunday, August 06, 2006 21:51 PM
To: obra@list.obra.org
Subject: Re: [OBRA Chat] TT Championships distance
Thanks for fessing up so graciously. We'd all like to deduct 80 seconds from
our times, but I have a hard time believing the course was a full 41 km,
since 25 mi is only 40.23 km, and the turnaround fell short of my memory of
where the old 25 mi turnaround was. At any rate, it couldn't have been more
than a hair longer than the old 25 mi course without running into
Harrisburg. So, how is the course measured, anyway?
--Doug Sears
_______________________________________________
OBRA mailing list
obra@list.obra.org
http://list.obra.org/mailman/listinfo/obra
Unsubscribe: obra-unsubscribe@list.obra.org
My GPS which is very accurate, said the course was 25.25 miles long.
Since a 40k is 24.8 miles, it means that we went .45 miles longer than
a 40K. Rounded up, approximately 1k which is .62 miles.
----Original Message----
From: mike.murray@obra.org
Date: 08/07/2006 3:49 PM
To:
Subj: Re: [OBRA Chat] TT Championships distance
The Peoria TT course has not been 25 miles since well before Candi and
I
were putting it on, which was at least 15 years ago. I don't know how
they
are determining the course length now but back when we ran it I
measured the
course several times with a measurement wheel applying a correction
for wear
on the wheel compared to measurement against a steel tape. I rolled
the
course out by skating with the measurement wheel and I placed a maker
nail
in the pavement every 1K. We used to go out and locate those marker
nails
and then spray paint mark the road and also place a cone with a
distance
sign every 1K. Unfortunately a few later the road was repaved and
most of
the marker nails were covered up. The county also got bothered by the
paint
markers and prohibited them in later permits.
Mike Murray
-----Original Message-----
From: obra-bounces@list.obra.org [mailto:obra-bounces@list.obra.org]
On
Behalf Of Doug Sears
Sent: Sunday, August 06, 2006 21:51 PM
To: obra@list.obra.org
Subject: Re: [OBRA Chat] TT Championships distance
Thanks for fessing up so graciously. We'd all like to deduct 80
seconds from
our times, but I have a hard time believing the course was a full 41
km,
since 25 mi is only 40.23 km, and the turnaround fell short of my
memory of
where the old 25 mi turnaround was. At any rate, it couldn't have been
more
than a hair longer than the old 25 mi course without running into
Harrisburg. So, how is the course measured, anyway?
--Doug Sears
_______________________________________________
OBRA mailing list
obra@list.obra.org
http://list.obra.org/mailman/listinfo/obra
Unsubscribe: obra-unsubscribe@list.obra.org
The Peoria TT course has not been 25 miles since well before Candi and I
were putting it on, which was at least 15 years ago. I don't know how they
are determining the course length now but back when we ran it I measured the
course several times with a measurement wheel applying a correction for wear
on the wheel compared to measurement against a steel tape. I rolled the
course out by skating with the measurement wheel and I placed a maker nail
in the pavement every 1K. We used to go out and locate those marker nails
and then spray paint mark the road and also place a cone with a distance
sign every 1K. Unfortunately a few later the road was repaved and most of
the marker nails were covered up. The county also got bothered by the paint
markers and prohibited them in later permits.
Mike Murray
-----Original Message-----
From: obra-bounces@list.obra.org [mailto:obra-bounces@list.obra.org] On
Behalf Of Doug Sears
Sent: Sunday, August 06, 2006 21:51 PM
To: obra@list.obra.org
Subject: Re: [OBRA Chat] TT Championships distance
Thanks for fessing up so graciously. We'd all like to deduct 80 seconds from
our times, but I have a hard time believing the course was a full 41 km,
since 25 mi is only 40.23 km, and the turnaround fell short of my memory of
where the old 25 mi turnaround was. At any rate, it couldn't have been more
than a hair longer than the old 25 mi course without running into
Harrisburg. So, how is the course measured, anyway?
--Doug Sears
Thanks for fessing up so graciously. We'd all like to deduct 80 seconds
from our times, but I have a hard time believing the course was a full 41
km, since 25 mi is only 40.23 km, and the turnaround fell short of my
memory of where the old 25 mi turnaround was. At any rate, it couldn't have
been more than a hair longer than the old 25 mi course without running into
Harrisburg. So, how is the course measured, anyway?
--Doug Sears
----- Original Message -----
From: "Steven R Holland"
To: "Doug Sears"
Cc:
Sent: Sunday, August 06, 2006 7:59 PM
Subject: Re: [OBRA Chat] TT Championships distance
Doug,
You are correct, the distance this year was 41K not the standard 40K.
To make a long story short and to avoid finger pointing....We made a
mistake :-(
This was a mis communication between us, EVC, and the officials.
However, we, EVC take full responsibility for the mistake.
The bad news is, you all had to ride 1K farther and you will not be able
to compare this years times to past years times :-(
The good news is.........You were not as slow as you thought!!!!
If you deduct about 80 seconds from your time this would give you a good
gauge as to what your 40K time would be.
Again, we, EVC take full responsibility for this mistake and I can
assure you next year you will do 40K...no more...no less.
Doug,
You are correct, the distance this year was 41K not the standard 40K.
To make a long story short and to avoid finger pointing....We made a
mistake :-(
This was a mis communication between us, EVC, and the officials.
However, we, EVC take full responsibility for the mistake.
The bad news is, you all had to ride 1K farther and you will not be able
to compare this years times to past years times :-(
The good news is.........You were not as slow as you thought!!!!
If you deduct about 80 seconds from your time this would give you a good
gauge as to what your 40K time would be.
Again, we, EVC take full responsibility for this mistake and I can
assure you next year you will do 40K...no more...no less.
Thanks to all the people who worked hard to make the OBRA TT Championships
a well-run event today. One little thing: I'm wondering why the 40 km
course was longer than last year. The four large brick posts in somebody's
front yard were an unmistakeable marker for last year's turnaround, but
this year we went well past that point. How is the distance measured, and
why was it re-measured this year? Which one is closer to 40 km?
--Doug Sears
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