100 miles in 5 hours challenge

[ColinJ]

I think we need a sister thread - the '100 miles in 4 hours challenge' because all these 4-and-a-bit hour centuries are making the 5 hour ones look a bit wimpy!

(As for those of us taking well over 6 hours ... )

 

[totallyfixed]

Just ran some estimations for the National 100TT, for the same power as in the M&DTTA at the weekend, I should do 03:55:50 +/- 00:01:46 (based on the current weather forecast which is bound to change between now and then of course). This is in line with @totallyfixed comment re. the Nationals course being 5-6 mins quicker, which is a good sanity check!

Better power only improves things of course and I am hoping to squeeze out an extra 5W!

Ok, we went over to check out the course yesterday, drove the A47 and a few miles after that then rode around the loop which included the "B" roads. First off it was very windy, secondly it is not flat, thirdly there is a section that has been chipped and it is the big aggressive chippings. To add to that there were 2 traffic light controlled roadworks, one of which may imply more chippings to come. I trailed dr_pink round on my roadbike, she on her TT bike at a pootle, we averaged 18.6 mph, two thirds of that was buffeted by the wind.
I am not going to go into detail here for obvious reasons but suffice to say I may have underestimated the difficulty of the course. This will not produce PB's, in fact I will go as far as to say that those who are used to riding drag strips are in for a bit of a shock .
PM me if you want more detail.

 

[Rob3rt]

Just for a bit of fun I have just run it for tomorrows 25 mile TT based on tomorrows weather forecast (and assuming my power output is 360W, I might fail to realise that but that is my target power) and the estimation is 55:26 +/- 24 seconds. I'll report back tomorrow what the actual time was. I will also re-run the estimator after the event with the actual weather data, rather than forecast data to see how well that works

Feeding back on this, my actual time was 55:48 (3rd place overall), which is within 22 seconds off the estimate (which was, as stated before assuming the average power would be 360W and with the weather data being forecast data).

The reality was I didn't do a good ride for various potential reasons, plugging in my actual race power and now using the actual historic weather data it says I should have been on 56:03. So again within 20 seconds of my actual time. I think that this a pretty great tool.

 

[Rob3rt]

Ok, we went over to check out the course yesterday, drove the A47 and a few miles after that then rode around the loop which included the "B" roads. First off it was very windy, secondly it is not flat, thirdly there is a section that has been chipped and it is the big aggressive chippings. To add to that there were 2 traffic light controlled roadworks, one of which may imply more chippings to come. I trailed dr_pink round on my roadbike, she on her TT bike at a pootle, we averaged 18.6 mph, two thirds of that was buffeted by the wind.
I am not going to go into detail here for obvious reasons but suffice to say I may have underestimated the difficulty of the course. This will not produce PB's, in fact I will go as far as to say that those who are used to riding drag strips are in for a bit of a shock .
PM me if you want more detail.

Cheers @totallyfixed, just got the nice little start booklet in the mail, will PM you later in the week Could be an upset in the results order you recon? Still thinking, fast is fast, so even if the DC warriors get a shock, I don't think it will upset any of them too much

 

[Rob3rt]

Still trying, blew at ~70 miles, power plummeted at that point, crawled home in 4:03:12 for 12th. Dr Pink PB'd with 4:28:55 for 5th in the womens field.

http://www.strava.com/activities/165672213

Still got the BDCA 100 left this year, sub-4 should be easy on there, I have other objectives for that event!

 

[TheJDog]

Someone want to fund time in the wind tunnel?

According to the Specialized wind tunnel videos they posted for a few weeks recently some sort of frame bag for the gels on your bars would help considerably.

 

[Joshua Plumtree]

Still a great time Robert - well done!
I see you beat our man by one place and one minute exactly!

 

[Herzog]

Giving this a shot tomorrow using this course. This is a fairly flat route for Switzerland, though it's still a reasonable amount of climbing 1890m (6,200 ft). On a recent ride I did 130km in 4 hours so I'm hopeful for a sub 5 hour time. However, it's supposed to be pretty hot here tomorrow (30 degC) and I'm not very good in the heat....we shall see

I'm expecting the climb at the end to be horrible!

 

[jarlrmai]

The climbing isn't so bad if you can really go full speed on the descent, it's when you climb up and then have to hold back on the descent where you lose time.

 

[JasonHolder]

Incorrect. On a 6 minute climb I can take off 2 minutes by pushing hard. Descending the same hill I can take off only 20 seconds by pushing hard.

You lose going uphill every time. Its about limiting loses. Going hard downhill is just not worth the effort.

 

[ColinJ]

The climbing isn't so bad if you can really go full speed on the descent, it's when you climb up and then have to hold back on the descent where you lose time.

Any climb that slows you down by more than 50% will be way slower overall, no matter how fast you descend.

For example - Let's assume you average 20 mph on a flat road but 8 miles up a tough hill at takes 1 hr 0 mins (8 mph). Descending that at an unrealistic 80 mph would take 6 mins. That is an average speed of only 14.6 mph.

 

[Archie_tect]

Query.... does GPS measure journeys simply on plan or the actual road distance travelled, ie the variation for recording the [hypotenuse] distances on slopes... that could make a significant difference to the distance actually travelled if you rely on GPS rather than a trip computer in hilly areas.

I may have asked this before but can't remember!

 

[jarlrmai]

Very true.

 

[jarlrmai]

The various apps have compensations, i've given up trying to work out which is better. Altitude is worse. My Garmin 810 will say i've done 1200foot then Strava from my phone will say it's 700foot that's a big discrepancy.

 

[Archie_tect]

Simplistically a 100 miles ridden measured on plan would actually be:
- 100.02miles with a 2% average gradient,
- 100.125 miles with a 5% average gradient, or,
- 100.50 miles with a 10% average gradient.

So, it's not as significant as I would have expected regardless of whether GPS measures just the horizontal distance or not- the up slopes themselves would be the big hurdle not the marginal extra distance!

Though if you are right on the limit of managing or not managing 100 miles in 5 hours it could become critical to be able to cycle a true 100 miles!