I am thinking of a 6.5hp rear drive.

JerboaJohn

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actually WM sells trailer wheels in all the sizes,, in-store tho might only carry 12 and 16". might be trial and error getting the wheels you like that work out fine for your plans
 


bike4life

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actually WM sells trailer wheels in all the sizes,, in-store tho might only carry 12 and 16". might be trial and error getting the wheels you like that work out fine for your plans
Urgent question.!!!!!!!! Should i have one wheel in the middle of the frame (unicycle) or a wheel on either end of the 5/8 stock (so totaling 2) almost like a tricycle....
 

JerboaJohn

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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
 

bike4life

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R u sure??? If so, ill do it... Just want to be sure because all the pusher trailer i see on the web actually have one wheel. Unfortunately, i cut the axle stock to one wheel, so i would have to spend 5 dollars do buy another and 5 dollars for another wheel...but it is what it is..

Right now i am not sure of the benefits of two wheel because with the trailer hitch and seatpost, the trailer physically can only go up and down and turn left/right for a turn, but not rotate or topple which would be bad and 2 wheels would stop that. I heard that trikes are somehow dangerous than their biccyled counterparts so i am not sure of the advantages of 2 wheels on either end.
 

JerboaJohn

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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
 

bike4life

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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
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....
 

JerboaJohn

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just have freetime now. sorry I didn't reply sooner.
10" tire ->10" pothole catastrophic event omg
5" hole devastating!
2.5" major shock but everything survives
1.25 dip very rough but no probs.
12" tire is 20% more smooth, higher speed, and gives 1" more clearance and last longer. the tire is the only suspension the trailer has, it can't flex knees to soak up small dips like you do on the bike. it'll pound thru them.
lemme do a diaphragm or 2 if can see what direction the push goes
 

JerboaJohn

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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
 

bike4life

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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
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??
 
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JerboaJohn

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since you already have 2 axis, keep it bcs slow speed turning will b easier. just to be safe, limit swing to something like 60 deg. if the turning radius is too big (like u gotta swing around in tighter than it lets u), you probably can cut the limiter a little, or grind down? I say 75 limit bcs if you are going more than ~15mph, 15 deg steering is pretty abrupt. faster than that, we lean more than turn the bars. you can't get into trouble below 10mph turning the bars like 20-30 deg. you'd put your foot down.
bcs it's one wheel, yeah I think you need a pivot. 2 wheels with one that turns free would do same thing but cost more to fab

ppl don't talk much about homemade bike trailers (esp. powered ones!) much so there's not much to go on. your experiences and pics can set a example to go by and improve on! maybe you'll be immortalized lol
 
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