Kyoto Cruiser with 2 Adults and 1 Child

Joined
Feb 28, 2022
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Indianapolis, IN USA
Greetings all. New member. I've been not riding much the last few years, because I work fairly long hours (but from home) and with all the other things I need to do, I can't take away from family time. I'm a big guy and gained my COVID weight over what wasn't light for 6'4" guy. So hoping to move family time to riding time somewhat. All three are excited about it.

I'm starting to get parts to build a Kyoto Cruiser with a centered rear child position. Initial Sketchup design work below. I widened a little in playing, but it looks like I'm better to go longer. I'll be drilling and tapping cranks for 130mm and 105mm positions. Our 5-year-old foster child that we will be adopting is 3'5" tall and I am designing the seat to be bolted or pinned with a front and back pin maybe a foot apart. This would allow moving it back as he grows without affecting the chain length (holes at 1" centers). This will cantilever the weight a little more as he gets heavier, so initially set up in front of the rear beam.

Question on this is what do people see as minimum chain line for a 3x7 setup? I will most likely have only rear setup for him at first and possibly locked into less than 7. But as he gains size and strength, I want to give the same range we have. I'm currently at 360mm or so from freehub center to crank center, which seems tight but doable. However, it would probably require not cross gearing unless I lock off the high front ring, etc. Would love to hear opinions on this. I'm working on the tradeoff on the triangle formed with more height of the rear BB and more forward position.

I think I will need a plate across the back for safety covering all the moving parts or a U leg channel.

Wife and kid would share a shaft, so they need to work together smoothly. I'll most likely share a shaft with an electric motor going into a 7 speed freehub if we take to this and want to make it a street safe for some streets where holding 25 mph for a bit to get past would be nice. I'm using a splined shaft with adaptors for freehub and freehub + disc made by Staton (https://www.staton-inc.com/store/index.php?p=product&id=182). I really worry about not being able to move things around and change freewheels for cog wear with chain if we ride this a bunch.

Due to the length and weight of me and my wife, I'm looking at using 1.5" x 3" beam for this main frame. This allows me to seriously up the strength while keeping the wall thinner, so best tradeoff for weight gain.

My plan is to work through this over the next year. Possible faster, but not sure. I need to practice my rusty TIG skills and get a permanent high amperage 220V run into the garage. My wife only takes so much unplugging the dryer and snaking a cord out the door.

 
Joined
Oct 19, 2012
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I think 360mm for a 3x7 will depend on the give in the chain you choose but would just about expect it to cope if the rear is centred to the 2nd ring. Best bet would be to lay some chain out and measure it's give.
 
Joined
Feb 7, 2008
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Nottinghamshire England
Hi there

In the long run would this be a better solution ?



The green trike could be the Kyoto so it could be smaller only having to carry 2 people ?
You would only hitch the orange trike when there was 3 going out.
Eventually your child [ or lone single adult out riding ] could have a trike of his own when old enough to handle it himself ?

Paul
 
Joined
Feb 28, 2022
Messages
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Location
Indianapolis, IN USA
I've thought about making the Kids portion attach with 4 bolts on each side of the back tube, probably with welded in hold support tubes so I can crank it down. Then I can remove this portion and attach the Sun USX Trike I purchased for my wife that she never really rode. But I'm left with a massive cargo area in 5-7 years. That isn't great. I'm going to talk with him and the wife and think through options.

I wanted to keep him close enough to easily talk, but looking at how far forward I need to be with our seat to clear the cranks, I don't know that gain much on a trailing bike.

I'll have to ponder this some. Thanks for the alternative thought process.
 
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Then I can remove this portion and attach the Sun USX Trike I purchased for my wife that she never really rode.
I wanted to keep him close enough to easily talk, but looking at how far forward I need to be with our seat to clear the cranks, I don't know that gain much on a trailing bike.

I'll have to ponder this some. Thanks for the alternative thought process.
Ok out the box thinking .....

As you already have the Sun USX why not reverse the combo ?

If you made a coupling at the rear of the SUN and attached it to the axle of the Kyoto front wheel [ leaving the wheel in ] you would effectively turn the Kyoto into a powered 3 wheeled trailer ?
You as the captain would pilot the Sun and your wife and son would be side to side on the Kyoto ? Perhaps a couple of motorcycle headsets for you and son would add to the sense of adventure when out on it ?

As when he grows up a bit they can then be split ?

Paul
 
Joined
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Location
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In some talks with the wife and kid this weekend, we have decided to build more stock Kyoto, but build a smaller delta as his first bike. I'll be looking at sizing down a DeltaRunner type to 20" wheels and X-Seam sizing from now to early teen crank distance.

I can then make a quick fork holder adaptor for the USX, until I get the Kyoto built.

For those building a Kyoto and going thicker than 1.5x1.5 14 gauge, instead of going to 11 gauge 1.5x1.5, go to 14 gauge 2x1.5 for stronger and lighter. (2" vertically oriented)
 
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In some talks with the wife and kid this weekend, we have decided to build more stock Kyoto, but build a smaller delta as his first bike. I'll be looking at sizing down a DeltaRunner type to 20" wheels and X-Seam sizing from now to early teen crank distance.
Have you seen the Rans Trizard ?




The front end seat and back end all clamp to a main boom so if you did the same as your lad grows all you need is a longer main boom ?
You might get away with only 2 booms as the above shows there is plenty on room for a over long boom to start with ?

Save you building 2 or more trikes.

Good idea for ALL the trikes to have the same wheel size , especially if you also plan to tow a trailer.

Paul
 
Joined
Feb 28, 2022
Messages
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Location
Indianapolis, IN USA
Completely agree on sharing tire sizes. One spare tube is much easier to deal with. My Greenspeed, USX, RANS Rocket all are 406, so keeping that.

My plan was to build a boom with the short setting at his current X-Seam (26") and give 12" or so of expansion. However, I also wanted to make the seat replaceable as it will need to grow.

This expanding/replaceable boom is interesting. I had looked at 1.75" square tubing as an over sleeve for cleaner movable BB. The seat mount could be 1.75" and join 1.5" tube from back and front. Although, I'm thinking that the complexity of this is more than just cutting and welding on a longer main tube in the future.

While I hate power side idlers, I want to keep the seat low enough to easily get in so I'll need to add an idler there. This is set up with BB at the current X-Seam of 26". Then I have about 14-16" of additional length, depending on heel strike.

 
Joined
Feb 28, 2022
Messages
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Oh, I like that rear hub using disc brake mount to run a chainring to drive the shaft (1:06 at above video). I might see if I can move that forward, instead of the idler... Hmm.
This is also a great place to fix 20" high-speed gearing issues.
 
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Oh, I like that rear hub using disc brake mount to run a chainring to drive the shaft (1:06 at above video). I might see if I can move that forward, instead of the idler... Hmm.
On mine I hope to mount a IGH hub instead of the idler , as you say a neat solution.
Don't forget for an adult you want it much further forward so you aren't climbing over the main boom AND the chain , as in your drawing aim for the boom at axle height and sling the hub under the boom.
On your drawing you really want the mid drive where the BB is shown !

This is also a great place to fix 20" high-speed gearing issues.
I just thought the Trizard main boom idea would provide a trike a bit less unwieldy and lighter for the smaller pilot whilst being expandable later on.

Depends how hilly it is where you live I suppose ? I run a 20" with a single 7 speed cluster and in some places need a 28T front @ 28T rear so direct drive !
I can just get away with a 36T front if I put more effort in.
That gives a top speed on the flat of between 11mph and 14mph , in all honesty plenty fast enough for most situations.
When touring I aim for an average of 10mph , so 11mph to 12mph gives that . anything faster and I free wheel to give the old [very ] legs a rest :giggle:

Paul
 
Joined
Jul 29, 2021
Messages
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Have you seen the Rans Trizard ?




The front end seat and back end all clamp to a main boom so if you did the same as your lad grows all you need is a longer main boom ?
You might get away with only 2 booms as the above shows there is plenty on room for a over long boom to start with ?

Save you building 2 or more trikes.

Good idea for ALL the trikes to have the same wheel size , especially if you also plan to tow a trailer.

Paul
Hi Stormbird:

Amazing project. I am building something similar, but I am concerned about the absence of a front brake. Do you miss it or notice a different kind of braking when only the back tire(s) are engaged?

thanks Dan de Angeli
 
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Dan de Angeli

The rule of thumb is you don't have ANY brake on a single wheel no matter what the configuration of the trike is.
Much to easy to lock the wheel up and have either a roll over tadpole or not steering delta.

if look at commercial trikes in the last few years they generally adhere to that rule.

However there can be exceptions ?

a brake on a single wheel could be a parking brake , usually triggered by a friction gear lever hidden somewhere under the seat [ deters people who try to ride the trike without your permission ? ]
or
I have heard of people riding a heavily loaded tadpole using a rear brake as a drag brake on long descent's . I suspect there are very careful !!!]

Yes there is some odd behavior of 2 brakes on the rear of a delta , it can steer slightly if one is applied on it's own and yes it can lock the rear wheels up occasionally however being able to steer in those circumstances is preferable to locking the front steering wheel up that just leads you directly to the scene of the accident.

Paul
 
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I'll echo Paul's comments. On a trike you generally want the bulk of your weight between the two wheeled bit for stability. This leaves the single wheel somewhat light. I've had tadpoles that would do a stoppie under braking which can be quite fun and controllable when expected. Also spinning the rear around deliberately can be fun when intending to do it as you come to a stop. What's not fun is a tadpole rear locking up mid corner, as all the weight leaves it for the front under braking, and attempting to overtake the front when you are already trying to avoid a crash by braking in the first place. If you are careful you can brake the single wheel but you do need to be very mindful of grabbing a handful and plowing straight on on a delta. A Kyoto would probably respond to a front brake better than most deltas simply due to two adults adding extra weight to the front.

There is also an issue of if you want three brakes then one hand has to pull two brakes. You can get levers specially designed to do this but that hand has to supply the effort of two. The best way in that scenario is to get a twin pull cantilever brake which is designed for a short cable pull and mate it to two discs. So long as you mount the discs square they can be set very close to the disc leaving a short pull length. This gives you the best leverage at the lever.

I can't speak for trying to catch a delta plowing on but there is precious little chance of catching a taddy that has let go at the rear unexpectedly. It's lightning fast between good grip at the back and none.

Having said all that and having swore never to rear brake a tadpole again I am doing just that with my current build - the Mk3 tilter. I want to see how bad it gets on a tilter (a very low one) and I can always re-cable it to front only if I decide it's unacceptable.
 
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Hey Popshot Stormbird et al

Super helpful. What I glean from all this is that I will plan to put two brake rotors on my rear axle and control each with single lever pull hand controls. The front wheels (I am committing to two smaller wheels, BMX in the front) shall have no braking. In another thread I was advised to think about using larger 200+ mm rotors for extra braking power, which I believe I will have room for. See attached image of the rear frame and pillow blocks.

thanks for the ongoing guidance.

Dan

 
Joined
Feb 28, 2022
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Location
Indianapolis, IN USA
For the trike, I'm making for our 5-year-old. I found a two cable pull (https://www.amazon.com/gp/product/B000AO7H16/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1) that I plan to use for both of the discs on the rear. Then I'll have a V-Brake on the front if needed. If the rear brake is enough, then I'll probably keep it as a one-level setup for simplicity. Although I like the redundancy of the front as well. I think that would more likely be useful when he gets bigger so his legs and weight load the front more.
 
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I always preferred the side by side one from Promax


The over and under design must pull the top one more than the bottom one.
 
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Hi there

not a fan of 2 brakes and one lever ?

Can't ease off a brake that is locking a wheel up ?
Can't signal and brake if signalling hand is brake hand ?

just my 2 pence worth ..[ $0.02602 ]

Paul
 
Joined
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Location
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I would agree with different brakes for someone understanding the controls when needing to stop. For a soon to be 6 year old, I think one lever to stop makes sense for simplicity.
 
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Joined
Feb 28, 2022
Messages
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Location
Indianapolis, IN USA
Using 2x2 6061 Aluminum in my Kyoto build. Have frame cut and cleaning out a place to build. Just received the 1.5x1.5 steel for child trike.

Using a 3" carbide hole saw for cutting hubs. Getting nice match to my tandem front hub I'm using.

 
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