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pileit1
05-08-2013, 09:34 AM
Hi guys. I've got a Street Fox in rolling chassis stage and I have noticed something peculiar. This is my first attempt at building a trike, or any bike for that matter. Oh and by the way, my welding skills are improving.:builder2:
ANYWAY, I had my first unpowered test drive last night!:punk: COOOOOOOOOOOL! One thing bothers me though. When I make a tight turn the steering wants to go all the way to its' extreme travel and it takes a fair amount of effort to bring it back to a straight track. Is this normal? My caster and camber angles are both at about 15 degrees.

All input, suggestions, and comments welcome. I'll have some pics at a later date, but it's your regular off the shelf Street Fox.

Radical Brad
05-08-2013, 11:10 AM
There is a point where the steering will max out, but usually this is well beyond what you would need under normal riding. The handlebars would normally hit your body before you would max out.

Brad

adrian
05-08-2013, 12:08 PM
it takes a fair amount of effort to bring it back to a straight track.

If the angles are out you effectively have to 'lift' the bike (and your own) weight to turn the wheels back to straight. The tendency to want to continue to turn once started is called 'steering flop'. Graucho's comments here might help - http://forum.atomiczombie.com/showthread.php/5230-Steering-flop-examples?p=49998#post49998

Cheers,
-Adrian

Ticktock
05-08-2013, 08:41 PM
Hi,
Just be aware that you are comparing apples and oranges! Grauchos' film is showing solo bikes, and you are talking about a three wheeler which stays upright!
Almost any wheel set up with normal angles will "flop" to full lock while stationary or at low speed, once it is turned away from straight ahead.
You are not likely to use full lock on a streetfox at full speed! (and stay on three wheels) Most Deltas will shake their heads at low speed if you let go- yet it takes no effort to hold bars straight. Cannot say if this happens on a tadpole, as I have not ridden one, but try to move a car with disonnected steering, and it soon goes full lock once disturbed from straight ahead.
Increase the speed, and it will straighten out.
Best to wait until you can do a proper road test, and if its OK straight ahead, maybe steering stops are needed to prevent getting more lock than you need.
Steve G,
beijing

pileit1
05-08-2013, 10:42 PM
YO,,,,ADRIAN!! :cheesy:
Thanks for the link. Graucho builds some righteous rides.
I got the chain installed and got to ride it around a bit under power but only in one gear and with shaky temporary seating. So the flop IS normal (as I had hoped) to some degree.I suppose that is good news, just have to be aware of it. NONE OF MY WELDS BROKE!!! I was probably more worried about that than anything.

Steve, I don't know if a car with the steering disconnected is the right analogy, but I get your point,,,,, so I guess maybe it is? This is my first trike, first tadpole, first recumbent, first DIY. I didn't have a good level surface to ride on so it's to early to say, but I don't think there's going to be any "look ma,, no hands!" with this ride. I think it needs a bit more toe-in and good tires properly and evenly inflated and............... So much yet to do but I'm stoked!

There's a great sense of satisfaction when you build something (That's right Barry, I built it) and it works as it should. I haven't had that feeling for far too long.

Rocky

Ticktock
05-09-2013, 09:25 AM
HI,Sounds like you are having a ball!
I think that if you think you need more toe-in, that you really need less toe -out! Any move from zero in either direction is going to cost you a lot of effort peddling.
Toe out will certainly not help in a "flop " situation, and may well add to it (not based on experience ) I would start with absolute zero if you can. Then introduce any toe in if it is really needed.
It does sound as if you may be able to turn your wheels further than you really need, but thats something you can work on when you start using it. Nothing wrong with an adjustable set of steering stops if that turns out to be the answer. And I bet it does track better at "speed" compared to "walk"
Steve G

Ticktock
05-09-2013, 09:29 AM
Hi again,
Just picked up on another point--don't worry about any wheel alignment until you do get those good tyres, same size, and evenly inflated!! You may have just told us where most of the problem lies!
Steve G