Lack of Steering Lock on B4

[burgie]

Right then, after hours of trying, I just cannot get my steerring lock to go full lock both ways. its only millimeters off, but the turning cricle from one side to another is obvioulsly huge.

not really noticed this as a problem until sunday just gone, when a fellow race turned his car round almost on its axis, and mine took just under the width of the straight!

the car has been built totally as per kit, but I have changed the position of the steering arms to the lower hole on the rack to try (unsuccesfully) to alleviate the problem.

I am now thinking the servo (KO 713) might be at fault, as it seems to turn even less when the car is on the ground.

Does anybody have any suggestions please?

[DA_cookie_monstA]

I think it is either a weak servo, or the spring on the servo saver has not been tightened down fully, allowing slack in the servo saver.

Also, have you followed the instructions and set the servo horn slightly off-centre (one spline to the right when you are looking at the servo horn.)

[burgie]

yes, the horn is one spline off centre, but I am not sure of the tension of the spring. i will check that tonight. There is what I think to be excessive play in the steering rack too.

[Chrislong]

Put some washers under the two screws holding the steering rack up, this minimises play without dragging on the movement. Also, there is a heavy duty spring available for the servo saver, this made a big difference for me.

Other than that, if servo is ok, try a losi servo horn as it is slightly longer.

Chris

[Dave G]

i think i filed my steering rack where the 2 shoulders were to take some slack away ..made a big difference.

the 713 isnt a bad servo..sure its not settings on your tranny??

dave

[burgie]

the tranny is set up so there is no exponential or sub trims to get in the way, and the steering gives full lock, and actually bangs onto the hub to turn left, but stops about three millimeters short when turning right. not a lot, but it makes a big big difference to the turning cricle.

I realise the servo is a good one, but it is about three years old now, and it has seen some impacts! I will swap it out, purely to see if that is the problem, and if it isn't then I'll stick it back in.

[DA_cookie_monstA]

Only other option that I can see affecting the steering is the fact that the turnbuckles may not be evenly adjusted, so it will give you more lock one way than another, especially if you have had to use the steering trim a bit to get the car to go straight.

[burgie]

yep, checked them, and they are exactly the same length as each other, which is spookily the same length as the 1:1 picture in the instruction manual. It is most peculiar.....

[Gaz_Stanton]

Check the aluminium nut that holds the spring down is fully tightened and not stripped. It may be loose but because of the steering design it doesn't actually fall off.
I had a problem once where the threads on the aluminium nut were too small in diameter. The nut would tighten fully when on the bench but as soon as any load was applied to the steering it would strip the composite steering arm and thus provide no tension on the spring. It took a while to find as the brace held it all together so there was no obvious breakage.
No more probs since installing a new nut though. :)

[rc_jammer]

When you say it turns full lock to left but not right is this with the tranny or when you move it with your hands??

If its with tranny then you have to adjust the lock from side to side, no car i have built has been able to run the same lock on tranny left to right. There is always a certain percentage difference.

If its with your hands then its something mechanical and could be many different things.
Where do you run your front hubs (top, middle or bottom) When i used to run mine in middle or bottom without any bump steer spacers the ball joint used to catch the wishbone on lock and prevented it from full lock.

[burgie]

it wont do lock to lock with the transmitter. the steering is perfectly free otherwise . . . . .

[burgie]

Gaz - Spot on - alloy nut and composite arm are the problem. The nut will tighten into the arm but without the pressure to hold it in situ.......

[Dave G]

mine was the same regarding spring..stripped when tightening it.

i removed the whole lot,put epoxy on the threads and pressed/screwed the nut on,placed in a vice and left overnight,never had problem again,or you could get the new uprated one.

dave

[BC Rog]

When I built my car I took an instant dislike to that assembly!

What i did was drill and tap the bellcrack parts so i could use a small screw to hold them together as a single unit. Still in there now and I've had no problems.

Give it a try. A small dowel or pin of some nature pressed into an undersized hole would do equally well.

Rog

[Gaz_Stanton]

Gaz - Spot on - alloy nut and composite arm are the problem. The nut will tighten into the arm but without the pressure to hold it in situ.......


Do I get a prize for that??? ;D :D

[burgie]

no gaz, just bask in the glorious sunshine of knowing that you were right. that's more than enough of a reward!

[Gaz_Stanton]

no gaz, just bask in the glorious sunshine of knowing that you were right. that's more than enough of a reward!


;D 8) 8) 8)