Local idiot tries to build a tadpole

[BionicOnion]

Ok, please bear with me. I had about 10 minutes today for a very quick layout for concept. Please excuse the other mess in the garage as well.

The rear wheel is just a spare 27.5 inch i had so I used it as a general idea, may go down to 20 inch wheel or 23 inch tire size, I don't know yet. The 2 red tubes will be vertically aligned and welded with some trellis reinforcement between them. The funnel is general front seat placement. The 2 wooden boards are where the front control arms would go. And the front bike frame will be cut off so just the downtube and bottom bracket are used, which should hopefully give me a nice leg stretch out for pedaling, room for suspension and any other components needed. And behind the front seat would be a spare seat/storage in the passenger area. In the picture between the rear wheel centerline and front control arms sets a wheel base of approx 60 inches, which is inline with a longer wheelbase tadpole trike. The little red tube below the front frame represents 7 foot from the rear tire centerline, used mostly for overall scale of production.

Please chime in with any thoughts, criticism, ideas, general tomfoolery or even fun jabs and thanks you for checking in!

 

[offGridDownUnder]

may go down to 20 inch wheel or 23 inch tire size

Decide this. Changing the relative front and rear wheel height will change the steering geometry.

 

[BionicOnion]

Decide this. Changing the relative front and rear wheel height will change the steering geometry.

Well, im hoping to be able to run year round. We get snow... a whole freaking bunch, so it almost seems like the slightly taller tire may be preferred at the cost of the extra weight and whatnot... or use the smaller wheels and find some snowmobile skis and run it that way? I live in a area where snowmobile is HUGE

 

[offGridDownUnder]

Well, im hoping to be able to run year round. We get snow... a whole freaking bunch, so it almost seems like the slightly taller tire may be preferred at the cost of the extra weight and whatnot... or use the smaller wheels and find some snowmobile skis and run it that way? I live in a area where snowmobile is HUGE

I can't be certain from your reply. I meant that if you weld the geometry with a 26" wheel in the back, and then switch to a 20" wheel in back, that 3" difference will change the angles of your steering axes.

You can find that your front wheels then fight each other and steering and tire wear will then henceforth be forever bad.

If you get the steering geometry correct, then I don't think there is some issue with going from 2" tires all around to 4" tires all around, as the steering angles would remain the same with respect to the road surface.

 

[BionicOnion]

I can't be certain from your reply. I meant that if you weld the geometry with a 26" wheel in the back, and then switch to a 20" wheel in back, that 3" difference will change the angles of your steering axes.

You can find that your front wheels then fight each other and steering and tire wear will then henceforth be forever bad.

If you get the steering geometry correct, then I don't think there is some issue with going from 2" tires all around to 4" tires all around, as the steering angles would remain the same with respect to the road surface.

Sounds to me like best bet would be say game on with 20s the whole way around. Ackerman shouldn't change much but I can see caster and toe shifting. But then depending on sai there's a chance of excessive scrub. Ideally I'd like 3 tires all the same so I only need 1 spare.

This things going to be pretty well equipped with motors for speed but still want to keep efficiency reasonable. The other nice part is if I make a change later I should be able to adapt for it

 

[classicalgas]

Ok, please bear with me. I had about 10 minutes today for a very quick layout for concept. Please excuse the other mess in the garage as well.

The rear wheel is just a spare 27.5 inch i had so I used it as a general idea, may go down to 20 inch wheel or 23 inch tire size, I don't know yet. The 2 red tubes will be vertically aligned and welded with some trellis reinforcement between them. The funnel is general front seat placement. The 2 wooden boards are where the front control arms would go. And the front bike frame will be cut off so just the downtube and bottom bracket are used, which should hopefully give me a nice leg stretch out for pedaling, room for suspension and any other components needed. And behind the front seat would be a spare seat/storage in the passenger area. In the picture between the rear wheel centerline and front control arms sets a wheel base of approx 60 inches, which is inline with a longer wheelbase tadpole trike. The little red tube below the front frame represents 7 foot from the rear tire centerline, used mostly for overall scale of production.

Please chime in with any thoughts, criticism, ideas, general tomfoolery or even fun jabs and thanks you for checking in!

Building a trike that works (steering is stable, nothing breaks, corners well without tipping over, etc...) is much more difficult than you imagine. If you can't find a used one, at least buy a set of plans from Atomic Zombie. That way you at least have some chance of getting the steering geometry right. Then you have to source wheels that will take the side loads of hard cornering, figure out a seat, brake mounts...

 

[BionicOnion]

Well I'm stuck here and hoping someone may be able to help. Attempting to lace up my temporary front wheels and I'm having issues with it. I tried following some spoke length calculations and lacing instructions for a 1x, but somehow a few spokes seem to long...but only a few. I guess its possible they are too long but if any experienced wheel lacing people can help id be very much appreciative. At this point I'm fairly certain all my spoke nipples are bottomed out

 

[gromike]

Watch the Grin how-to video on wheel lacing, and take it apart and start over. When I had that very same problem I started the pattern wrong.

 

[ZeroEm]

If they are all bottomed out then the only thing todo is to get shorter spokes. But how much shorter? you don't want to just keep buy spokes until they fit. Need to go back to your spoke calculations and find what is wrong did you measure the rim correctly!
Take your time, lacing your own wheels is a good skill.

 

[BionicOnion]

Thanks guys, ill undo it. I tried using a grin video how to, but i think it was an April fools joke....it went... bad lol. So I retried with a park tool video and got much much closer. What's odd to me is only a few spokes are too long...and they aren't all together. Oh well....attempting #3. All about the journey

 

[offGridDownUnder]

All about the journey

As another poster here observes...

"Good judgement comes from experience.
Experience comes from bad judgement."

Enjoy the ride. Let us know what you find out this time.

 

[The Toecutter]

Well, im hoping to be able to run year round. We get snow... a whole freaking bunch, so it almost seems like the slightly taller tire may be preferred at the cost of the extra weight and whatnot... or use the smaller wheels and find some snowmobile skis and run it that way? I live in a area where snowmobile is HUGE

For snow, you're going to want AWD. My own personal experience is that with any scenario where there exceeds an inch of snow, a RWD tadpole is just going to spin the drive wheel. I have thousands of miles of snow/ice riding, but only after the streets have had an initial plowing.

 

[The Toecutter]

Building a trike that works (steering is stable, nothing breaks, corners well without tipping over, etc...) is much more difficult than you imagine. If you can't find a used one, at least buy a set of plans from Atomic Zombie. That way you at least have some chance of getting the steering geometry right. Then you have to source wheels that will take the side loads of hard cornering, figure out a seat, brake mounts...

Caster alignment and toe-in alignment are both commonly neglected on amateur builds, but proper setting will help the trike track straight at speed.

McPherson struts are also perfectly adequate suspension, and I recommend a minimum of front suspension with at least 1.5" travel and nothing less. Preferably full suspension.

 

[Chalo]

Caster alignment and toe-in alignment are both commonly neglected on amateur builds, but proper setting will help the trike track straight at speed.

Easiest by far is to have wheels vertical and parallel to each other, and on good rigid axles that don't flex and sag. Cambered wheels introduce all kinds of BS for marginal benefits, and are rarely if ever worth it.

 

[The Toecutter]

Easiest by far is to have wheels vertical and parallel to each other, and on good rigid axles that don't flex and sag. Cambered wheels introduce all kinds of BS for marginal benefits, and are rarely if ever worth it.

Agreed. My 3 degree negative cambered wheels wear my front tires out prematurely, so much so that front tires are the largest component of my operating expense, at $0.01/mile, and I wear them out until they are bald.

 

[BionicOnion]

Agreed. My 3 degree negative cambered wheels wear my front tires out prematurely, so much so that front tires are the largest component of my operating expense, at $0.01/mile, and I wear them out until they are bald.

Sounds like you guys are recommending a 0 camber, but using caster and toe for proper tracking yes?

 

[Chalo]

Sounds like you guys are recommending a 0 camber, but using caster and toe for proper tracking yes?

If there's no camber, then you don't need toe-out to counteract it. Caster is another matter that relates to kingpin angle, wheel size etc. In the '90s I used to work with Rickey Horwitz, but I don't know what he knows about that stuff. So I won't dispense any advice that would likely be in error anyway.

 

[The Toecutter]

Sounds like you guys are recommending a 0 camber, but using caster and toe for proper tracking yes?

Recommended reading:

https://www.amazon.com/Chassis-Desi...ed-Automotive/dp/B00HMU9SV8/ref=sr_1_1?sr=8-1

It can get very complicated.

 

[BionicOnion]

Recommended reading:

https://www.amazon.com/Chassis-Desi...ed-Automotive/dp/B00HMU9SV8/ref=sr_1_1?sr=8-1

It can get very complicated.

I have an automotive background so the theory of the angles in the macro i understand, I am planning on front suspension, it is good to hear even a little camber does cause extra wear in these cases and to set a 0 camber and probably going to try to design adjustability into it for...future needs

 

[BionicOnion]

Update...disassembled the entire wheel at lunch as you guys recommended... found 21 long spokes...and 7 shorter... uggg... I need to be better organized lol. Im surprised it was as good as it was

 

[offGridDownUnder]

found 21 long spokes...and 7 shorter..

Water the short ones and put them in the sun for a week?

 

[ZeroEm]

Update...disassembled the entire wheel at lunch as you guys recommended... found 21 long spokes...and 7 shorter... uggg... I need to be better organized lol. Im surprised it was as good as it was

A mm makes all the distance. You want the threads to end up in the head not below it, the nipple could break off.

 

[Chalo]

Update...disassembled the entire wheel at lunch as you guys recommended... found 21 long spokes...and 7 shorter... uggg... I need to be better organized lol. Im surprised it was as good as it was

If those spokes are bigger than 2.00mm, ditch them.

 

[BionicOnion]

If those spokes are bigger than 2.00mm, ditch them.

I measured them at 2.0. They are 13ga. Thank you though

 

[Chalo]

I measured them at 2.0. They are 13ga. Thank you though

13ga is 2.34mm.

When you use spokes that are too thick, you reduce the load that the wheel will carry reliably, and you get an assortment of problems that could be avoided by using thinner spokes.