Oct 13 (a)

Oct 13, 2004

SLOOOOW fairing progress..

Second coating of drywall mud and still bumpy

Man this is taking a long time! I would be WAY further ahead if I had simply shaved down the raw pink foam shape because it was fairly easy to carve to an acceptably smooth surface. Instead, I filled in the stair-step edges at the top, bottom and nose with expanding foam and drywall mud as you can see in the above photo. The mud takes a while to harden, and when it does, it's WAY slower to sand it smooth than the original foam. I'm using a 60 grit sandpaper, but maybe that's not enough because it's just taking way too long to smoothen out these bumps. I have an power sander also, but I prefer longer strokes that you can only do with your arms.

I think I'm going to stop with this coating of mud and put one layer of fiber glass over the whole thing to keep it strong and solid. I had planned on coating the glassed plug with a 1/8" layer of bondo, then proceed to surface finish the plug but, I think I really need to simplify this initial fairing experiment because I just don't know how I'll need to change the fairing yet. I really need to just get this general shape onto the trike and get it onto the road to learn more.

Other unknowns are:

1. How to mount the fairing on the trike
2. Room inside the fairing to move and cycle
3. Visibility over the fairing top
4. Fairings reaction to cross winds
5. How stiff and strong the fairing needs to be - and exactly WHERE it needs to be strong (floor, mounting points, ribs??)

Any or all of these unknown variables will effect the next version of the fairing - so I don't see the need to invest a lot of time into producing a perfectly glossy beauty yet.

When I get it all figured out, then I can either re-design the fairing from scratch and have a proper mold CNC cut from MDF or foam at HeavyIndustries - or, I can modify the current plug and then proceed to polish the surface to a mirror-like finish. The point is, I'm hesitant to put any more time into this current plug shape because I just don't know how I might need to change it yet.

TCR1 49" track width test ride

I added two flashing red lights to the back, and finally mounted that second rear disc brake. I did that yesterday when it was a perfect 24 degrees C (75 degrees F) and went for a 40km ride today in freezing 9 degrees C and pouring rain.

It's definitely wide on the road and vehicles have to move over into the oncoming lane to pass me on shoulderless stretches of road. This wasn't really a problem because traffic was light and visibility ahead for the vehicles passing was good. It would definitely be an issue on a shoulderless or narrow shoulder road with lots of hills and or curves. On the large shoulder roads, there was plenty of room between me and the traffic, and I just fit between the rumble strips and the edge of the road - so that was OK.

As far as cornering stability goes, I never did get it to lift a wheel during my cul-de-sac corner tests and I could hang a hard right turn at 30 kph (but I think I could also do that with the 32" track).

Bump steer was still an issue - or maybe I should restate: bump steer still felt the same as the narrow track. It may not really be an issue because nothing bad has ever resulted from a bump steer so as Bob Rohorn suggests, it may just be a matter of getting used to it.

There was an unexpected issue though.... There was this weird oscillation at certain speeds (probably other unknown conditions like road surface, etc contributed to it as well). The front wheel wobbled very quickly from side to side. Looking at the rear wheels, I noticed they were also partaking in this nervous dance.

What happens is because of the longer lever in the rear, small forces now can produce larger effects and this results in some vibration that perhaps wasn't even noticable before becoming a nuisance The problem could easily be fixed by reinforcing the triangle from the front wheel back to each of the two rear wheels - but, this is a lean steer and the front section of the bike needs to pivot freely. Wide wheel tracks won't work on lean steers unless the pivot is fixed at both the front AND the rear (like Bobs S'trike)

To summarize, there were certainly more problems with this J.low rear end than there were advantages. The ride didn't feel different in any way - even cornering forces still 'felt' the same. It was equally as rigid as the old bottom strut reinforced 31" rear version. Bumps at speed were still producing a bit of a steer jerk and the oscillation caused by the long levers to the rear wheels was annoying. Add to all this the inconvenience of having to always be concerned about your displacement on the road and other motorists, I would say this width - or anything even close to it is not worth looking into further.

I think I will return back to my previous svelte 31" rear end and try adding a bit of camber to see how that effects things.

Hey - you learn best by TRYING right?

A lizard in Calgary?

I saw this thing crossing the road today. So I slammed on my brakes and went back to take a picture of it. At first glance I thought it was a lizard (gecko or newt), but they don't live where it snows.... I guess it's some kind of salamander - but where it came from I haven't a clue. There wasn't any slews around that I could see. Strange...

Here are some center of gravity calculations from Ben Eadie:

Surprisingly, they show that the center of gravity is almost perfectly in the mid point between the front and rear wheels (I had thought it was closer to the front wheel). C of G closer to the rear wheels is better for cornering stability, but moving the rear wheels forward causes a very twitchy feeling ride - way less stable at higher speeds. Moving ME backward to accomplish a more rearward C of G can't happen because of the front wheel having to fit between the bottom bracket and me. So it looks like I have a pretty decent configuration as far as lean steer geometry goes.

2 Due LIST:

1. Buy and install right brake (FINALLY ordered it!)
2. Invent new cable tensioner to allow more steering bar turn radius
3. Add front derailleur
4. Order 20mm axle bolts for the rear wheels (I'm using 1/2 inch now which isn't right)
5. Design and machine 2 seat mounts out of aluminum to replace current steel ones (e-machineshop.com) LATER.
6. Design and machine 2 steering tensioners out of alum to replace LATER
7. Order a new front wheel! (Helen is kind of upset that I am user her Zipp race wheel!)
8. Start work on the first fairing (starting now)
9. Invent steering stiffener
10. Add larger chain ring and modify chain stays
11. Make clamp-on out riggers and try to flip it (changed to#25)
12. Fabricate new steering bar (aluminum or composite?) or rework existing
13. Lathe an aluminum collar for .5" hub axles (Ben E. said he'd do it for me) (That didn't work - James is doing it for me now).
14. Design and build a trainer to fit mag trainer (donated by Michael Hoenig).
15. Replace steel cables with Kevlar (maybe not - I think the flex of steel is good....)
16. Crotch guard / fender
17. Narrow chain stays to allow foot to clear
18. fix derailleur
19. crank hitting chain stay
20. chain stay frame flex?
21. Narrow, high density foam for seat
22. Make front quick release safety
23. Change steer cable sheaves to Pete Heals idea
24. Add missing and new webs
25. Add a g-meter and quantify turning g's at flippage threshold. (add outriggers)
26. Widden the track width to 42 inches and test.
27. Solve the rear stiffness issue (If the wider track is good, then build a whole new rear triangle)

TOTAL distance on TCR1
605.9 km

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