UpDown 2

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Finally got both wheels laced and trued.
Fitted on axle.

First thought when seen on table was, "This thing is too long, won't be stable".

So I shortened up the weelbase again.
Even if that means that the back rider will be sitting behind the rear axle.

That also plays havoc with the proposed drive train.
Need to reconsider what to do.
First thought about that is to use another 3-speed hub instead of freewheel.
on wheels re.JPG
 

Ulu

Stinky Old Fish
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I feel it wants to pick up the inside wheel on a turn. Off-camber turns would be deadly. With two riders and a case of beer down low, you might keep it on Earth.

But as a caveat, I only rode one trike after childhood. An HD 45 servicar, stripped with Mickey Thompsons. Slow and stable and too fat to fit between parked trucks. It just stalled from idle, and I had to kick it. There was a bent coathanger to hold the pedal up. Booger had about 50 psi compression and started as easily as it stalled.

I decided not to buy it. :grin:
 
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Off-camber turns would be deadly
That is the trade off for having your lawn chair on wheels.
Also deadly is dropping one wheel off a curb while on a sidewalk.
The slower speeds and lower center of gravity help.
Careful riding also helps.

I will consider making room for the 'case of beer' down low,
however that is one lesson I learned back in 1974, beer drinking and peddling don't mix well.
 
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Hi,
It is no surprise when the reality of a build turns out different than the sketch.
Easy to make things work on paper, not so easy when building.

By shortening up the wheel base, things started to get tight.
SOP for me, design as work is in progress.

Today's goal was gearing choices, and steer stick for the back.

Will be using the headset, and the adjustable bars from the Bike E I bought
to use the dual drive hub on the 'frakentrike".

The headset looks like 1 1/4 . Can't use the aluminum head tube from Bike E, so need to find
something else.
Here is a donor fork and piece of chain link fence pipe for the steer tube.
donor fork and fence pipe re.JPG
 
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This is the fork I cut to extend the steer tube on the "Intense" race frame bike, and now i will
use the center part.
The fence pipe is just the right size for the longer steer tube needed for UpDown 2.

The "headtube" will be a bit more trouble. Finding some scrap tubing that will accept the
Bike E headset cups is not happening, so I will make something.
Starting with a piece of tube cut from an inversion table, close , but not right, the ends are cut,
spread out with a 1" deep impact socket, hammered around the socket, then welded up.
And then the cups fit.
expanding with socket re.JPG
Bike E headset re.JPG
unwelded package re.JPG
steer tube and fork ready re.JPG
 
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The gearing part was complicated by the shorter wheelbase.
I wanted to use a 3-speed hub in the middle. Have one to use.
After shortening up, that needed to move back more to leave room for feet when peddling.
That put the 3-speed too close to the rear cassette, so the next plan was for yet another 3-speed
hub out back.
Couldn't find one close by to recycle.

That led to "robbing" the dual drive from the 'frankentrike", (sorry frank).
Put that back together with lower gearing so no real loss.

The middle 3-speed hub might be too close to the rear one to use all the cassette gears,
but I hope to use at least 3, or maybe 4.

gearing 1 re.JPG
gearing 2 re.JPG
 
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Let me be very clear.
I really admire the clean , precise, professional welding and workmanship that many of the
other builders show here on RRB.
Also the clean shop spaces and work areas seen here.

Alas , that has not been my style for many years. I can spend 3 hours cleaning up.
and have things right back to messy in 1/2 hour.

I am inspired by what I've seen here to try a bit harder to keep up with the mess .
 
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Got all the rear chains installed.
Things worked out surprisingly well for a first attempt.
i will need to buy a "half link" to correct the slight slop in the rear dual-drive to axle cog chain.
Even with the short distance from the front 3-speed to the rear dual drive, the chain shifts
fine for the three largest cogs.

Also fitted a front BB and customcobbled chainring and chain.

Now that I have the gear train worked out, the missing back part of the bottom tube
can be made. Need to miss the chain. And then welded in.
updown 1 re.JPG
updown 2.JPG
updown 4 re.JPG

Then the frame will be strong enough to test sit on. (often a temp plywood seat)
Add a steering link and it's first test ride time.
( slow. level gravel. no brakes. )
 
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For this build, the rear trike frame part, will bolt solid to the front frame.
Will end up with several brace points and gussets.

The front BB is solid to the frame, the slack taken up by the adjustable BB.

After that is tight, the middle or front 3-speed can be adjusted backward to take up the slack
from the adjustable Bottom Brackets second chainring.
Am using the slot in the trike frame that is normally used to adjust the axle chain for this.

Then the derailleur for the dual drive takes up the slack from the front 3-speed to the dual drive.

Used the back part of low end 10 speeds to mount the dual drive. Just welded on the back.
So it can be adjusted backward to take up the slack to the axle cog.

Used a part that also had a derailleur mount on it.
 
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