JerboaJohn
Well-Known Member
- Joined
- Jul 29, 2018
- Messages
- 1,272
2 wheel, for stability bcs whatever you put in the trailer might be shifted off-center, asymmetric, etc. just toss stuff in, get going,, easiest
should i upgrade my tire diameter. like at 10" can that handle bumps and pot holes. The gap between the bottom of the frame and ground is 3", when accounting for 5" radius - .5" pillow block -1.5" of w channel means 3" clearence between road and bottom of frame. also the tires in the very back not the middle, so its not like the back will hit the road as if the tire was closer to the front....you can do 1 wheel, but if it only had 1 contact point with the bike, it's possible it could lean opposite your direction and a turn could be "interesting"
I haven't felt what a single wheel trailer does, just think of the force vectors. when i get home, i can get on the pc and draw a couple graphics.
go ahead with what you have! lean can be dealt with as an add on
ok so heres what i can do.... when i built the hitch, i designed it for 2 axis. My trailer length is 35". So what do u think i should do, add a stop block to the hitch so i cant exceed like 75 degrees or should i just weld the swing part shut as a solid entity. The question is would i actually be able to make turns without the hitch swing part. Like in trucks and stuff, i think they have a ball hitch? My trailer is 15" by 35" so if i have a tongue length of 1/2 or 17.5" that forms an acute triangle with sides 15" base w/ 17.5" height. Cut triangle in half to get right triangle. To find angle tan^-1(7.5/17.5) which is 23 degrees. 23*2=46 degree pivot angle because i cut it in half. Personally i am thinking of adding stop blocks to restrict the swing to 75 degrees. what do u think??View attachment 86963
without getting into hairy geometry, a couple principles show up just seeing the angles. I found the longer the tongue, reduces the pivot angle. perfection in turns would be an infinitely long tongue, catastrophic failure is a certainty at pivot angle above 90 degrees. to scale, this is a 3 x 2 trailer with tongue 1/2 of trailer length. you can see the angle is ~75deg. already approaching a bad situation lol (15 deg steering input and you're in trouble at a moderate slow speed.)
juggling some vectors, I see best is actually no pivot from the top looking down! you don't want a trailer 8' behind you, you'd like it close as you can get, like 6" or less from your back tire. at any length of tongue this'd make a really big pivot angle, so we remove the pivot and the trailer can only steer you through your handlebars, which you have control, and this makes the lever arm of any torque from engine very long, and gentle for you to control, regardless if it's 1.5hp or 6.5 haha.
with 1 dimensional hitch (vertical movement only), the tongue length is from handlebar stem to the drive axle. comfortably long, simplest design. add a flexible hitch like a ball, and the force vectors multiply the uncomfy steering torque and possible jackknife situations are there @ any tongue length less than 1/2.
so the simplest connection to the bike is solid, but up/down movement is good and safe. 1 horizontal bolt to the trailer
1 drive wheel or 2 makes no difference in this model
lol. yeah back in the day when i was younger, lol i am only 16 y do i talk like that?, i used to be a math geek tried to learn calc back in 8th grade and figured out half of the stuff. in 8th grade i was kinda fascinated when i cut out a parabolic shape on paper just for kicks and figured out its center of mass with a calc formula and then balanced it on a pencil and it matched the data from the formula. tho i was always viewed negatively for this and i gave up interest more or less. still believe that if u know the math and physics u can hack life. I still do well with math and visualize all the math/physics that i get at skool. I have a terrible memory like barely can remeber ppls names and what i ate or did an hour ago so i was forced to invent the equations or intuition instead of remebering them for tests and stuff. Tho its bad b/c i go to a medical highschool and we have anatomy physiology(instead of engineering and math stuff, 0 stem ciriculum) and medical terms in latin and i do terrible on them as medicine is straight up rote learning... btw the intention of this was not to brag just in casegood math! tho I calculate stuff, when you see it enough times, you can have an idea of angles. 90-(23)=67 and ball park close to what I conservatively thought is a safe limit angle. you're good to go
don't wanna get into load weight and momentum equations on turns esp when more variables like braking, accelerating from speed x
now you know why vehicle designers are a team and they all make big bucks, taking 2-3 years from scratch to build any vehicle!