ECHO

[tjwilson]

Getting a late start but, better late than never I suppose!

I put in a lot of ride time this past summer and fall. More often than not my bike of choice has been my last year's MBBO entry "Twist of Lemon". Love the bike but, lots of little things I would do differently to increase its ride-ability if I were to do it again. That's kind of where the design idea for this bike began. Here's a the punch list of what I wanted to address:

- Less weight, "Twist of Lemon" is a *heavy* bike.
- Lower center of gravity.
- Shorter wheel base.

The weight of "Twist", where it's concentrated, plus the majority of the weight in the fork being in front of the steering axis made for a heavy steering feel. Add to that a wheelbase that put the rear axle back pretty far and I ended up with a bike that doesn't have as snappy of a feel to it as I think it potentially could.

- Adjustable seat position

Be nice to have the bike fit another rider than just me.

- Simpler drivetrain and braking setup.

I wanted to simplify the overall look and fabrication just because and, maybe a little laziness worked into the equation too. Fitting curved tubing at compound angles is fun and challenging but also takes a lot of time and patience. I struggled for a while to hit upon a design. I just couldn't come up with something I liked enough to get excited about the fabrication and fitting that would be required. After backing up a bit and starting fresh I came up with this mostly straight line design. Really reminds me a lot of Apollo/Screamer/Eliminator/Chopper MK designs. Not a bad thing.

Simplification and ride-ability also influenced a lot of the part selections. I'm going with mostly new parts this time around rather than refurbishing older components. Sealed bearings for the bottom bracket and headset, an internal geared hub with coaster brake for the rear, and a disc brake hub up front. The rear wheel is a 24 x 50mm Felt 3-spd conversion upgrade kit. This uses a Nexus 3-spd and twist shifter. I haven't decided for sure if I'll use the twist shifter or try to come up with some type of stick shift. I'm using the same 24 x 3 Innova tire for the rear that I used last time even though it's heavy. I just like the look. The front wheel is a 20 x 31mm rim with a 90mm sturmey-archer disc brake hub and 20 x 1.75 tire.

 

[tjwilson]

Front Wheel

This is my first try at lacing a wheel. I now have a new found appreciation for all of you who do this all the time. Took a couple attempts but I think I've got it. In the process I found a pretty cool online calculator that calculates spoke lengths and graphically displays the angle that the spokes will enter the rim. Really helped me settle on a cross pattern:
ebikes.ca/tools/spoke-calc.html

A big question I still have is how to determine proper spoke tension. Hopefully someone with experience can offer up some advise?

 

[Glen]

Nice

Your builds are always good to watch. Twist of Lemon was yellow, I suppose because lemons are yellow... But what colour is an ECHO?

Glen.

 

[The Renaissance Man]

Looking forward to this. Your builds are always inspiring!
Cool dropouts.

... But what colour is an ECHO?

Glen.

The same colour it was before it came back.

 

[OddJob]

My experience with spoke tension is mainly 'hands on'. There are tension tools, if you want to be really precise. (and from the looks of your drawings and build approach, I have a feeling you might fall into that category ! )

I have found over the years, that you can get spokes very close to the same tension by squeezing two 'same side' spokes closest to each other. By squeezing pairs of spokes around the wheel, you'll get a feel for the tension and getting them all in the same range.

I'm not sure if you said if you were using a truing stand or not? That is a helpful tool. And somebody like you could easily fab one up. The most important thing to remember, that it's very small turns on the spoke wrench. An 1/8 of a turn or 15 degree turn can make a big change.

If you have a hop to one side when truing, pick the two spokes opposite the hop, that pull from the opposite side of the hub, one on each side of the hop and do a small adjustment by tightening each of the two spokes. At a certain point, if after going a few rounds on both sides of the wheel and you have spokes that feel too tight when trying to adjust, then you may have to loosen the spoke on the side of the hop instead of tightening the opposite side spokes.

You'll find that after doing a few wheels, your hand built wheels will be far superior to any that come on a factory made bike. I'm no ultra pro, and use a home made truing stand, but I can put one of my hand built wheels on a bike and get absolutely no 'pinging' of spokes, the sound of spokes re-tensioning and 'settling in'. That's why the hands always tell the truth.

 

[GuitarlCarl]

I've only done a few simple lace jobs with spokes the same on both sides (no dish) but tightening them all equally a little at a time, working my way around the rim repeatedly has worked very well for me. If you hand check any factory laced wheel you'll feel different tensions and I think that alloy wheels are very forgiving. But I'm right there with OJ, equally hand tensioned wheels just feel right. I use a MTB rear triangle from a suspension bike I scrapped, with a couple zip ties for pointer gauges, as a truing stand and find that it works well for me.

Carl.

 

[restodave]

The fancy tools for testing tension of the spokes basically squeeze adjacent spokes together and read out a number. Your fingers are probably precise enough, just compare tension to a similar known good wheel. When I build a wheel I get all the spokes finger tight by twisting each nipple about a turn or two at a time then I go with a spoke wrench turning each nipple about the same amount until the tension feels about right.

My trick for finding and fixing the wobbles is a felt tip pen like a Sharpie. Hold the pen just close enough to the rim as it spins to make contact with the out of true part of the rim, then tighten the spokes on the side opposite the mark. The same works for wheel hop but then you tighten spokes on both sides of the rim that are near the felt pen mark.

These shade tree mechanic techniques work for most coaster brake and internally geared wheels, it gets more complicated if you're building a wheel with a multi-speed cassette (the dreaded dish). They may be a job for a professional.

 

[LukeTheJoker]

He is in!
Looking forward to seeing this!

 

[tjwilson]

Nice

Your builds are always good to watch. Twist of Lemon was yellow, I suppose because lemons are yellow... But what colour is an ECHO?

Glen.

Thanks. I suppose if I'm trying to be cleaver I'd go with purple... straight across the color wheel from yellow, complimentary/contrasting color and all. Then there's always the potential to stay with a citrus theme... a lime green or orange maybe? I have some white glitter vinyl for the seat that's a definite. A high gloss black might look really cool with that. So yeah, I have no clue what color yet!

 

[tjwilson]

Looking forward to this. Your builds are always inspiring!
Cool dropouts.



The same colour it was before it came back.

Thanks, glad you like the dropouts. High praise from the Drop Out King... wait, what? That doesn't sound quite like the compliment I intended.

 

[tjwilson]

Thanks @OddJob , @GuitarlCarl , @restodave for the feedback on wheel building. You've given me enough confidence to give it a go myself.

My intentions had always been to just get the spoke pattern set and take it in to have it trued. After I got the spokes in, and an initial tightening, I was surprised how straight and centered the wheel already was. I'll definitely be trying the fork / zip tie trick to straighten it further. If I understand right I just need to tighten the spokes as evenly as possible till they feel correct. I've got wheels I can compare to for correct feel. Also sounds like the wheels will "talk back" if tension varies too much between individual spokes.

 

[tjwilson]

He is in!
Looking forward to seeing this!

Hope you'll be dipping your foot in. The water's fine!

 

[Imaginos]

Regarding the color, since it’s an echo should you consider the Doppler effect? Rather than purple, maybe a yellow/green. Or am I being obtuse?

 

[tjwilson]

Regarding the color, since it’s an echo should you consider the Doppler effect? Rather than purple, maybe a yellow/green. Or am I being obtuse?

Lemon-lime?

 

[OddJob]

Lemon-lime?

Now if it were a kid's bike you could call it a 'Sprite'....

 

[Indyjps]

Good to see you building wheels, youll be looking forward to it each build now.
My truing stand is also the rear triangle from an old bike, i welded on a flat plate to hold magnetic base for dial indicator, many times I just use the rod the indicator clamps on instead of the dial. Also welded on 2 angle iron "feet".

On your design, will the bars laid that far forward effect your steering. Anytime i go forward of vertical with the fork it steers funny to me ( bmx 20- 26" is my reference)

Cant wait to see this one come together

 

[OddJob]

Good to see you building wheels, youll be looking forward to it each build now.
My truing stand is also the rear triangle from an old bike, i welded on a flat plate to hold magnetic base for dial indicator, many times I just use the rod the indicator clamps on instead of the dial. Also welded on 2 angle iron "feet".

On your design, will the bars laid that far forward effect your steering. Anytime i go forward of vertical with the fork it steers funny to me ( bmx 20- 26" is my reference)

Cant wait to see this one come together

Slightly off topic, but I'd like to see that truing stand Indy!

 

[tjwilson]

Good to see you building wheels, youll be looking forward to it each build now.
My truing stand is also the rear triangle from an old bike, i welded on a flat plate to hold magnetic base for dial indicator, many times I just use the rod the indicator clamps on instead of the dial. Also welded on 2 angle iron "feet".

On your design, will the bars laid that far forward effect your steering. Anytime i go forward of vertical with the fork it steers funny to me ( bmx 20- 26" is my reference)

Cant wait to see this one come together

I second the request for an image of the stand!

I've set up other bikes with the bars forward like that before. It does feel a little funny at first but I get used to it pretty fast. I'm pretty sure there is a handling penalty. Having the bars forward though is probably the least of the handling compromises I've made in the name of something I've convinced myself is a "grand" design vision.

 

[Indyjps]

Didnt want to clog up the thread. But its TJs show.
I already had the magnetic base dial indicator. If i was to critique the project, a wider plate would have helped. Dial indicator is best for new, high quality rims.

The dial indicator will show any variation, for used rims or cheap rims, many times ill just use the arm, it sqeeks on the rim edge and lets you know youre not quite there.

I keep it spaced for rear rims and use a stack of washers for front rims.

 

[tjwilson]

Thanks @Indyjps for the pics of the stand. I might just have to build something similar, I'll definitely build a wheel again. I can even see maybe using the brake posts to hold some type of adjustable pointers?

Here's a couple images of the temporary "stand" I cobbled together for this project. The initial rim centering was pretty close. The scale taped below the rim helped adjust the centering a little better. As it got closer to center I just flipped the wheel occasionally till the distance was the same to the zip-tie indicator on both sides. Vertical hop was minimal and I was able to get nearly all of it out pretty early into the truing. Tightening the spokes slowly was a big help. Took a while, a couple hours but, toward the end I'd learned enough from earlier adjustments that I had a good idea of how the wheel would react before I tightened a spoke.