Bottlehead race sponsorship

[Tom-s]

Could you share a link on here Doc?

This sounds good through Crack / HD 800's!

[Doc B.]

It sounds way better with the baffles out  We have quite a bit of video from the event, that Jim Laurel will be crafting into a mini documentary. I will post links when I get them.

[Doc B.]

https://komonews.com/news/newsradio/kitsap-man-sets-a-new-speed-record-as-others-his-age-begin-slowing-down

[Doc B.]

Interview starts at 19:50

http://mynorthwest.com/category/podcast_player/?a=75a2d4e6-1964-40da-b02c-a960014f16ed&sid=1004&n=The+Dori+Monson+Show

[Doc B.]

So I walk into Central Market to see if I got in the newspaper...

[kgoss]

Congratulations Doc!  Quite an achievement and it’s great you are being recognized for it.

On a side note it’s awesome to see something as old as me (born in 1962) going that fast. 🏍👍

[Doc B.]

I have put up video of my rookie land speed run on YouTube

[Tom-s]

Headphone users! Mind the volume level!

Looks great Doc!

[debk]

I know this topic is old.

What is anything are you allowed to do to reduce drag of the bike/rider combination?  Fa

Deb

[Doc B.]

I'm running in what is called a naked class. That means no front fairing, which is generally considered to be worth about 5-15 mph. So the aero treatment body-wise is limited to what you can do to the front fender and what you can do to the seat. Other than that it's all about reducing frontal area, rider position (a.k.a. tuck) and maybe lengthening the wheelbase up to the allowed 10% to improve the Cd a little. There are a zillion other little details, like tight leathers, proper gearing, etc. to obsess over. And horsepower (a.k.a. where the bulk of the money goes). I'm deep into beefing up my motor for this August, so I can give it a much bigger shot of nitrous than last time without breaking things. At least that is the theory. In 2019 I put a valve adjuster screw through a valve cover on my third run.

Here's a video of my second run from 2019, with nitrous injection, a better clutch and a bit more practiced technique. Once I'm on the bottle I'm running about 10 mph faster than in the previous video. Hoping to add another 5 mph this year.

[Paul Birkeland]

This?

[Doc B.]

I'll take two bottles, please. Losing weight has only a tiny effect on top speed. But it sure would make my leathers more comfortable.

[debk]

i wonder if small vortex generators would have any effect of improving laminar flow around the rider.  It would probably take wind tunnel testing/modeling for placement.  don't know if this would be allowed.

Interesting sport

[Doc B.]

I have considered it. Like putting VGs along the edges of my arms and legs and at the hunch in my back. The math for the speeds I run works out to the vortex generators being about 1/32" tall or something equally silly. There was a time a few years ago that one of the pro cycling teams had little bumps on the arms of their jersey sleeves. The calcs for that kind of stuff at cycling speeds are like you gain .3 seconds over 30 miles.

One thing I plan to try down the road is lengthening the rear swing arm 5", which would allow me to create a relatively long tail on the back of my seat the width of my butt and tapering back to and end even with the rear of the rear wheel. That is one of the few aero things allowed in my class and it should help improve Cd. The old saw in land speed circles is "Don't worry about the hole you open in the air. Worry about how well you close it."

My plan for the past couple years has been to use photogrammetry to model the bike and me in my leathers. I imagine you know about the online CFD analyzers like simscale. My hope is to get a decent 3D model and run a CFD analysis of different riding positions, components, etc.