noise and strange clunk when applying full steering lock...

The Hoff · Post by **The Hoff** » Wed Mar 21, 2007 11:43 am

Hi all,

It's probably nothing major but.. when I reverse out of my warehouse I have to apply full righthand lock of the steering. When doing so I get to a point where it goes "clunk" and there is definite feeling that comes through the steering wheel. It doesn't do it when I apply full lefthand lock though..
I don't notice anything otherwise when driving and she seems to steer perfectly..

Should I be worrying about it ? or should I just ignore it?

It was an ex-demo car for it's first 1500 miles until I bought it.. and I have been very carefull with it.

cheers,

Cowan

Novice Racer · Post by **Novice Racer** » Wed Mar 21, 2007 11:52 am

Interesting.

I also need full right steering lock to get out of my place in the morning. I get a couple of what feel like "jumps" from the steering, as if I have reversed over a couple of pine cones. Never tried it on full left lock.

I thought that this might be something to do with the geometry of reversing. By this I mean that with the steering on full in reverse, the front of the car is trying to go more sideways than the back (which has the weight of the engine and the drive on the rear wheels) will allow. This drags the sideways pointing front tyres backwards slightly say once or twice when friction is lost and this movement between the front tyres and the road is felt as a bit faint of jumping the the steering.

Fully expect to be

over my amateur assessment.

NR

The Hoff · Post by **The Hoff** » Wed Mar 21, 2007 12:13 pm

Novice Racer wrote:Interesting.

I also need full right steering lock to get out of my place in the morning. I get a couple of what feel like "jumps" from the steering, as if I have reversed over a couple of pine cones. Never tried it on full left lock.

I thought that this might be something to do with the geometry of reversing. By this I mean that with the steering on full in reverse, the front of the car is trying to go more sideways than the back (which has the weight of the engine and the drive on the rear wheels) will allow. This drags the sideways pointing front tyres backwards slightly say once or twice when friction is lost and this movement between the front tyres and the road is felt as a bit faint of jumping the the steering.

Fully expect to be over my amateur assessment.

NR

...Well your experience mirrors mine.. I do get what feels like I have reversed over something.. can't comment on your technical assessment though.. sounds plausible, but I'm not technically minded enough to add to it.

cheers,

Cowan

dezzy · Post by **dezzy** » Wed Mar 21, 2007 1:14 pm

Interesting . . . something similar happens to me when I reverse (to the right) out of my driveway. I always assumed it was just the clunk of the front left going down into this really annoying pothole right at the end of my driveway. It always feels like I've went over something or into that pothole. Not sure if I actually hear a clunk though.

Rich H · Post by **Rich H** » Wed Mar 21, 2007 4:14 pm

Pretty sure mine does that too.

If nothing obvious is hanging off, stop using full lock....

Novice Racer · Post by **Novice Racer** » Wed Mar 21, 2007 4:37 pm

I don't hear a clunk as such, just feel it through the wheel as described above. Never had any other steering issues so I assume its just a feature of full lock in reverse (steering rack probably not designed specifically with this in mind).

NR

alicrozier · Post by **alicrozier** » Wed Mar 21, 2007 5:00 pm

Yup, steering geom on lock in reverse builds up lateral loading in the tyres until they 'jump'. Pretty much all cars will do it just more noticable in the Elise as your not so isolated from the steering (which is a good thing).

Novice Racer · Post by **Novice Racer** » Wed Mar 21, 2007 7:03 pm

alicrozier wrote:Yup, steering geom on lock in reverse builds up lateral loading in the tyres until they 'jump'. Pretty much all cars will do it just more noticable in the Elise as your not so isolated from the steering (which is a good thing).

Hooray! I think I might have guessed a technical issue right

Novice Racer wrote:Interesting.

I also need full right steering lock to get out of my place in the morning. I get a couple of what feel like "jumps" from the steering, as if I have reversed over a couple of pine cones. Never tried it on full left lock.

I thought that this might be something to do with the geometry of reversing. By this I mean that with the steering on full in reverse, the front of the car is trying to go more sideways than the back (which has the weight of the engine and the drive on the rear wheels) will allow. This drags the sideways pointing front tyres backwards slightly say once or twice when friction is lost and this movement between the front tyres and the road is felt as a bit faint of jumping the the steering.

Fully expect to be over my amateur assessment.

NR

k12chu · Post by **k12chu** » Wed Mar 21, 2007 7:24 pm

alicrozier wrote:Yup, steering geom on lock in reverse builds up lateral loading in the tyres until they 'jump'. Pretty much all cars will do it just more noticable in the Elise as your not so isolated from the steering (which is a good thing).

i have the same problem with my car, but while turning left. the surprising thing is, this little jump (as if the tyre went over a small stone) happens only on a cold start. once i drive the car for a mile or so, it doesnt happen untill the next cold start

The Hoff · Post by **The Hoff** » Thu Mar 22, 2007 10:09 am

...well.. it seems there is nothing to worry about then. Thanks for the explanations

Cowan