Luxurious turning circle [Archive]

SPQR

18-01-2008, 02:57 PM

yfin

18-01-2008, 06:01 PM

Tramlining is caused mostly by the width of the tyre and the tyre tread. I also moved to 17" rims from the standard tyres and found it followed the road too easily with 225 wide tyres and directional tread.

The thing is changing to a 235 wide tyre and a non-directional tread significantly reduced the tramlining.

Merlin086

18-01-2008, 06:33 PM

Does anyone know why the Luxury with 17" wheels has a larger turning circle than the Standard?

I found a previous post about fitting the Honda Luxury/Sport 17" wheels to the Standard that mentions the turning circle but nothing really illuminating on the subject.

http://www.ozhonda.com/forum/showthread.php?t=45243&highlight=turning+circle

My car is a 2004 Standard to which I have fitted Luxury 17" wheels. It tramlines badly. The 17" wheels have the same offset as the 16" wheel. I wonder if the front suspension geometry is different? It might explaining the different turning circle and the tramlining.

Does anyone know?

I would have thought maybe a larger rolling diameter for the increase in turning circle.......

Damn, are those wheels still tramlining SPQR!.......:thumbdwn:

Only ever noticed a slight tramlining in the first month when new before you bought them, and the Avanti 17" that replaced them have a offset of 45mm.

Still a very slight tramlining effect, but then after lowering 45mm on Tein coilovers a month later I have found in almost a year now that the car goes wherever I point it with no tramlining except a couple of times on extremely grooved roads, but only then minor.

I have only just replaced the Bridgstone RE040 with Pirelli Dragons, and it seems even more direct.

Is it possible the steering geometry was altered between the 03-05 and the 06 on?
I had heard their was some suspension mods between models

EuroDude

18-01-2008, 07:55 PM

Merlin086

18-01-2008, 08:07 PM

The rolling diameter of the wheel between the stock 16" size and 17" size is only about 0.36% (17" uses lower profile tyre to near-match the 16" tyre), so the turning circle would be virtually identical.

The original 17" bridgestones have a drifting problem, so when its time to change, get some Pirelli Dragons or Yokohama C-Drives (Ive had both on my euro and they dont tramline or drift)

I dont think the suspension changed between the 03-05 and 06-08, but I know that the suspension of the Base model is different to the Luxury/Sport model.

As I stated above, I've been running the stock Bridgestones on my 06, and tramlining is almost non-existant, and reduced after increasing the track 20mm and lowering.

I don't think SPQR was running stock Bridgestone after purchasing the rims for his 04 and did so in a attempt to stop the tramlining, and is still getting severe tramlining.

That says to me it isn't the tyres at fault......

SPQR

19-01-2008, 12:52 PM

I would have thought maybe a larger rolling diameter for the increase in turning circle.......

Is it possible the steering geometry was altered between the 03-05 and the 06 on?
I had heard their was some suspension mods between models

Hello Merlin086!

The 225/45R17 tyres of the Luxury and the 205/55R16 tyres of the Standard have virtually the same rolling diameter and the the 17" wheels and the 16" wheel have the same 55mm offset.

The Honda Australia website specification lists a turning circle of 10.8m for the Standard and 11.2m for the Luxury. Check the "Dimensions" tab at the following page:

http://www.honda.com.au/wps/wcm/connect/internet/Honda.com.au/Home/Showroom/Accord+Euro/Specifications/

This to me suggests a difference in suspension geometry between the Standard and Luxury.

I remember that when the Luxury came out standard with 17" wheels, Honda said that the Luxury suspension was changed to suit the 17" wheels. I thought this was only to make the suspension softer to compensate for the reduced sidewall height but it might also have included a geometry change; perhaps to reduce tramlining.

I did try 17" wheels with the stock Bridgestone RE030 tyres. These were aftermarket with 45mm offset. The tramlining was quite evident. I did not think that Honda 17" wheels would have the problem.

The thread that I quoted in the first post (above) talked about a Honda Dealer telling a member that the 17" wheels would not fit the Euro with 16" wheels. Maybe there was a good reason for this.

I don't think the tramlining is such a problem on the Luxury as it is with the Standard fitted with 17" wheels.

Merlin086

19-01-2008, 01:05 PM

Hmm, as the theory goes the main factor is supposedly the tyre width, so you should have noticed a increase in tramlining going from 205/16 to 225/17?

SPQR

19-01-2008, 02:37 PM

I did not experience any tramlining with the standard 16" wheels and 205/55R16 tyres.

What I am suggesting is that the Luxury with 17" wheels has a larger turning circle resulting from a different front suspension geometry that might be so designed to counteract what would otherwise be the severe tramlining that would be experienced if the 17" and 225 section tyres (with straighter sidewalls) were fitted to the Luxury without any suspension changes. The tramlining is thus more evident on Standard Euros fitted with 17" and 225 section tyres because they were not designed for the wider section tyres.

The section width is the cause of the tramlining but, I suggest, Honda has counteracted this by changing the front suspension geometry of the Luxury to suit.

The 235 section tyres mentioned in a post above would ameliorate the problem because if fitted to the Honda 17" x 7" wheels, the sidewalls would be more rounded. This section tyre is not designed to fit a 7" wide rim.

I think that fitting 225/50R16 tyres to the 16" rim (correct rolling diameter) might also cause tramlining.

JohnL

19-01-2008, 02:45 PM

Hello Merlin086!

The 225/45R17 tyres of the Luxury and the 205/55R16 tyres of the Standard have virtually the same rolling diameter and the the 17" wheels and the 16" wheel have the same 55mm offset.

The Honda Australia website specification lists a turning circle of 10.8m for the Standard and 11.2m for the Luxury. Check the "Dimensions" tab at the following page:

This to me suggests a difference in suspension geometry between the Standard and Luxury.

I remember that when the Luxury came out standard with 17" wheels, Honda said that the Luxury suspension was changed to suit the 17" wheels. I thought this was only to make the suspension softer to compensate for the reduced sidewall height but it might also have included a geometry change; perhaps to reduce tramlining.

I did try 17" wheels with the stock Bridgestone RE030 tyres. These were aftermarket with 45mm offset. The tramlining was quite evident. I did not think that Honda 17" wheels would have the problem.

The thread that I quoted in the first post (above) talked about a Honda Dealer telling a member that the 17" wheels would not fit the Euro with 16" wheels. Maybe there was a good reason for this.

It suggests at least a steering change to me. Assuming that the 17" wheels (fitted with wider tyres) are also wider in the rim than the 16" wheels fitted with the narrower tyre, or even only because the only tyres are wider, if the larger wheels have the same offset as the smaller wheels then the larger wheel and wider tyre will extend farther inward into the wheel well. This could mean interference problems with either bodywork or suspension components at full lock.

To address this Honda may have simply decreased the limits of lateral rack motion (?), thus a bigger turning circle.

SPQR

19-01-2008, 02:57 PM

It suggests at least a steering change to me. Assuming that the 17" wheels (fitted with wider tyres) are also wider in the rim than the 16" wheels fitted with the narrower tyre, or even only because the only tyres are wider, if the larger wheels have the same offset as the smaller wheels then the larger wheel and wider tyre will extend farther inward into the wheel well. This could mean interference problems with either bodywork or suspension components at full lock.

To address this Honda may have simply decreased the limits of lateral rack motion (?), thus a bigger turning circle.

I don't know if Honda reduced the limits of lateral rack motion/full lock position of the Luxury: The 17" wheels fit the Standard Euro without interfering/touching with the suspension or other internal wheel-well objects. I have never encountered this even in hard cornering with the suspension fully loaded.

I still think the geometry change and larger turning circle might be so to address the tramlining that would otherwise happen.

Exar Kun

19-01-2008, 03:51 PM

JohnL

19-01-2008, 07:17 PM

I don't know if Honda reduced the limits of lateral rack motion/full lock position of the Luxury: The 17" wheels fit the Standard Euro without interfering/touching with the suspension or other internal wheel-well objects. I have never encountered this even in hard cornering with the suspension fully loaded.

I still think the geometry change and larger turning circle might be so to address the tramlining that would otherwise happen.

You may be correct, but keep in mind that hard cornering doesn't necessarily mean hard cornering at full lock. Just because the tyre may never actually touch anything on full lock in practice (or when you've been cornering hard) doesn't necessarily mean that Honda may not have increased the clearance just to be absolutely certain it never happens. The design engineers may have a minimum clearance they never go under as a matter of principle or policy (?).

If other geometries have been altered to address any tramlining issues, I do wonder just what they might be. The only thing that springs to mind might be decreasing scrub radius (associated with wheel offset relative to the steering axis, so could be changed more easily with offset than suspension component alteration), but I'd imagine scrub radius would probably be minimal in the first place (?).

If you fit wider tyres then an increase in tramlining would be to be expected, the most practical way to address this to whatever degree would be to use tyres with a softer sidewall, even if in handling dynamic terms this might mean you take one step forward and one step back (or maybe two steps forward and one back as the wider rubber will give slightly improved grip levels).

Keep in mind the probable main reason for Honda to fit wider rubber (or offer it as a more expensive option) will likely be percieved customer demand for wider rubber, i.e. most people assume wider will be better (true or not, depending on the application, less so for front drivers not driven on baby bottom smooth race tracks), and also tend to just like the way it looks.

Honda may then choose a wider tyre with a relatively soft sidewall to pre-empt complaints about excessive tramlining, even if this might mean the OEM wider tyre offers relatively little dynamic improvement over the narrower OEM tyre with the taller but stiffer sidewall (??).

SPQR

21-01-2008, 09:47 PM

The design engineers may have a minimum clearance they never go under as a matter of principle or policy (?).

If other geometries have been altered to address any tramlining issues, I do wonder just what they might be. The only thing that springs to mind might be decreasing scrub radius (associated with wheel offset relative to the steering axis, so could be changed more easily with offset than suspension component alteration), but I'd imagine scrub radius would probably be minimal in the first place (?).

Honda may then choose a wider tyre with a relatively soft sidewall to pre-empt complaints about excessive tramlining, even if this might mean the OEM wider tyre offers relatively little dynamic improvement over the narrower OEM tyre with the taller but stiffer sidewall (??).

I agree. I expect that the Honda design engineers probably do have minimum clearances. They probably designed the Euro to be fitted with 225/45R17 tyres on 7" wide rims at some stage. I think that they even come with 18" rims on some European models (if not optional).

They did alter the suspension of the Luxury compared to the Standard when they introduced the 17" wheel on the Luxury. Who knows to what extent they altered it.

I'm no suspension expert and certainly you sound like you know what you're on about. I've read some of your other posts. I could not begin to know what else they might have altered or what they could alter to counteract tramlining.

One thing is known; wider tyres and straight/hard/square sidewalls = tramlining.

As far as I know, the Bridgestone RE030 fitted to the Luxury is a high performance tyre with straight/hard/square sidewalls. But Luxury owners don't seem to report severe tramlining whereas my Standard fitted with the Honda 17" wheels and 225/45R17 tyres tramlines to a such an extent that I'm driven to distraction.

Honda should not just tell people that the 17" wheel is not to be fitted to the Euro Standard as suggested in another thread. They should say why.

JohnL

21-01-2008, 10:24 PM

I agree. I expect that the Honda design engineers probably do have minimum clearances. They probably designed the Euro to be fitted with 225/45R17 tyres on 7" wide rims at some stage. I think that they even come with 18" rims on some European models (if not optional).

They did alter the suspension of the Luxury compared to the Standard when they introduced the 17" wheel on the Luxury. Who knows to what extent they altered it.

I'm no suspension expert and certainly you sound like you know what you're on about. I've read some of your other posts. I could not begin to know what else they might have altered or what they could alter to counteract tramlining.

One thing is known; wider tyres and straight/hard/square sidewalls = tramlining.

As far as I know, the Bridgestone RE030 fitted to the Luxury is a high performance tyre with straight/hard/square sidewalls. But Luxury owners don't seem to report severe tramlining whereas my Standard fitted with the Honda 17" wheels and 225/45R17 tyres tramlines to a such an extent that I'm driven to distraction.

Honda should not just tell people that the 17" wheel is not to be fitted to the Euro Standard as suggested in another thread. They should say why.
It might be educational if we could know the relative sidewall stiffnesses of these different tyres. Tread stiffness may also be involved. We might find the tyre fitted to the 'Luxury' is not a stiff as we are assuming...(?).

I couldn't think of what might be changed in the geometry other than scrub radius that might reduce tramlining. But, thinking about this, whatever else it might be could only be associated with the steering axis's relationship to the nominal centre of the contact patch (i.e. where within the confines of the contact patch the steering axis intersects the ground) and thus the manner in which forces generated at the contact patch are fed into the steering via the steering axis, which could only mean the degree of trail.

Decreasing caster angle would also decrease trail, and this may mean forces generated at the contact patch are not felt as strongly at the steering wheel, so the driver doesn't have to work so hard to keep the wheels straight (i.e. the driver would have more leverage on the wheel direction as tramlining affects are occuring). Do you know if there is any difference in caster angle between the standard car and the Luxury?

SPQR

21-01-2008, 10:41 PM

Sorry JohnL, I don't have that information. I don't think that Honda dealers give that sort of information freely.

Manuals of for the USA Acura TSX can be had online apparently but that model only ever came with the 17" wheels; interestingly with a 215/50R17 tyre which has a slightly larger diameter more rounded sidewall than the 225/45R17.

SPQR

12-04-2008, 03:46 PM

I thought I'd ask Honda why there is a difference in the turning circle between the Standard and the Luxury and why the 17" Honda wheel is not available as an accessory for the Standard. The following was the response from the technical department:

"Thank you for your recent contact regarding wheels and the turning circle for the Honda Accord Euro and Euro Luxury.

The two items that you mention regarding the fitment of accessory wheels and the turning circle are linked. You are unable to fit the 17inch alloy wheels on the standard Accord Euro as they will impinge on components it (sic) the front suspension. To remedy this on the Accord Euro Luxury different front suspension and steering components have been employed to reduce the amount of steering angle available."

I bet that the suspension differences also account for the tramlining suffered by the Standard when fitted with 17" Wheels!

aaronng

12-04-2008, 05:20 PM

You are unable to fit the 17inch alloy wheels on the standard Accord Euro as they will impinge on components it (sic) the front suspension. To remedy this on the Accord Euro Luxury different front suspension and steering components have been employed to reduce the amount of steering angle available."

Does anyone with a base model euro have 17/18/19" rims with 7-8.5" width rims and 225-235 tyres experience rubbing when turning full lock?

hooyn

12-04-2008, 11:15 PM

I have a lux, 18" 8.5" wide 225 tyres no rubbing.

but you want to know base model.

anywho.

JohnL

12-04-2008, 11:55 PM

I bet that the suspension differences also account for the tramlining suffered by the Standard when fitted with 17" Wheels!

The changes are to limit rubbing of the larger tyres by by limiting steering lock. Since we're betting, I bet these changes to the 'Luxury' (whatever they actually are) don't affect tramlining behaviour. I bet they do limit the degree of lateral rack motion (either by changes to internal rack 'stops' or external steering arm 'stops'?), but would be very surprised if the changes are of the sort that would have any affect on any geometry that affects steering or handling characteristics.

Without being able to ascribe guilt beyond reasonable doubt, I would still be tending to point the finger at the tyre.

PS Why 'SPQR'? Roman connection?

tony1234

13-04-2008, 01:32 PM

When we picked up our 2008 Euro Lux (with stock 17" wheels) the car would follow cambers aggressively and was already starting to tramline. I changed the one-week old RE040s for Michelin Pilot Preceda 2's and the difference was night and day. Straight away the car tracked straight regardless of the road surface. No tramlining at all, and camber-following was much reduced.

The only diference was the tyres - the wheels alignment wasn't touched. To me that say's it's the Bridgestones are at fault. At least on my car. ;)
Same thing with my car as well.ChangedRE040s for Conti Sport contact 2s and the car tracked better.i have mine lowered as well.

Merlin086

13-04-2008, 03:27 PM

My 06 lux had minor tramlining until lowering and replacing with 17x7's with a 45 offset.
No tramlining and is the most directional car I have ever driven!...and this has been running the RE040's until 29k's.

Have had the Pirelli Dragons on for 6k now, still no tramlining but the grip ability of the Pirelli Dragons is very disappointing in the dry compared to the RE040's, as the limit of adhesion is only about 75% of the bridgestone.

SPQR

13-04-2008, 04:46 PM

The only diference was the tyres - the wheels alignment wasn't touched. To me that say's it's the Bridgestones are at fault. At least on my car. ;)

I did have secondhand 225/45R17 Bridgestone RE040's on my Euro Standard (with 17 inch wheels on loan but with 45mm offset) and there was tramlining present in large doses. I then got a set of the 10 spoke Luxury wheels from Merlin086's car (55mm offset) and fitted the same secondhand 225/45R17 Bridgestone RE040's. The offset did not make any difference. The tramlining was just as bad. Then I got new Dunlop SportMaxx tyres and the tramilining was much diminished but still present. The tyres are over a year old now and the tramlining is now just as bad as the Bridgestone tyres.

I wonder if the Michelins will also misbehave once they're run-in or older?

One should be able to fit any quality tyre without getting any tramlining.

Before my Euro I had the 2001 Civic 5 door. I fitted 225/45R17 Dunlop tyres to it (OK, they were slightly oversize) but there was never any hint of tramlining.

It seems to me that once tyres get any sort of distance on them, they will all "cause" tramilining on the Euro. Therefore, there must be a suspension geometry design fault that causes all brands of tyres to eventually tramline.

Merlin086 had tramlining with the Euro Luxury 17" wheels with the Bridgestone tyres.

I assume most people in the southern states drive on smooth roads and so tramilining is not evident. Darwin has had and is having a massive building and development boom and so many of our roads are furrowed from the weight of trucks. The Government here doesn't acknowledge the problem lest someone might link the accident rate to the state of our roads. Instead, they constantly tell us we are very naughty speeders and that our wallets/purses need to be taught a lesson.

SPQR

13-04-2008, 04:55 PM

PS Why 'SPQR'? Roman connection?

Italian citizen? Alluding to the authority of the Senate and the People of Rome (Senatus Popules-Que Romanus)? I don't know. Maybe I just like the Roman standard at the head all the Roman armies and buildings and everything else the Romans touched. Or maybe a reminder of people power: Vox Populi Vox Dei (The voice of the people is the voice of God) which is a reminder to politicians and people in power to behave or they'll answer to the people.

Merlin086

13-04-2008, 06:20 PM

[QUOTE=splashalot2000;1633593][QUOTE=SPQR;1633566]

I wonder if the Michelins will also misbehave once they're run-in or older?.........It seems to me that once tyres get any sort of distance on them, they will all "cause" tramilining on the Euro. Therefore, there must be a suspension geometry design fault that causes all brands of tyres to eventually tramline.
QUOTE]

Sorry,got to disagree.....

After my initial minor tramlining when my lux was new, once my suspension was modded any tramlining had virtually disappeared, and this did not change as the Bridgestone RE040 tyres approached the end of their life, if anything I would say they became more directional and responsive...:thumbsup:

aaronng

13-04-2008, 07:18 PM

If it was tramlining, I would put it to the suspension setup of the Euro, not really the tyres.

Merlin086

13-04-2008, 07:40 PM

If it was tramlining, I would put it to the suspension setup of the Euro, not really the tyres.

Difficult call but I would have to agree.......:thumbsup:

aaronng

13-04-2008, 08:05 PM

Difficult call but I would have to agree.......:thumbsup:

I say that because suspension geometry has a larger effect on tramlining than tyres (assuming that the owner has not done something silly like using totally wrong offsets or a width that is not suitable for the car). When you get the perfect suspension geometry that doesn't tramline, then you can observe the effect of the tyres. Otherwise, the effect of suspension will mask the effect of the tyres.

tony1234

13-04-2008, 08:17 PM

When i lowered my car with the Bilstein/Eibach combo and changed the tyres i now have next to no pulling/tramlining.I now have 36K on the Conti's now.I would have thought doing these things would have increased the tramlining/pulling!!:confused:

SPQR

13-04-2008, 08:41 PM

If it was tramlining, I would put it to the suspension setup of the Euro, not really the tyres.

Hello Merlin086. The gist of the paragraph you quoted from my post was that I postulated that it is the suspension geometry of the Euro that is manifested in the tramlining of lots of different brands of tyres. Virtually no matter what tyres you put on the Euro, the suspension will make them tramline once the "sheen/skin" has worn off the tyres.

You mentioned that you modified your car's suspension and have eliminated tramlining (great!) but at the same time you said that you disagreed with what I said. aaronng then said what I have quoted above (which is the essential gist of my post) and you agreed with him.

I think we've got our wires crossed. We (you aaronng and me) appear to be in agreement. The suspension is likely to be the culprit. It's just JohnL that knows better than us.

SPQR

13-04-2008, 08:45 PM

aaronng

13-04-2008, 11:53 PM

The new Accord does not tramline. I've driven one and it tracks straight; no matter how rutted or grooved the road surface. I drove it over the same roads that would have my Euro darting all over the place and it just went exactly where I pointed it. Why can't my Euro do that?

Because the Accord and Euro have different suspension geometry. It could be that in order to achieve the Euro's handling, a compromise had to be made which allowed more tramlining. *just guessing here*

SPQR

14-04-2008, 06:54 AM

Because the Accord and Euro have different suspension geometry. It could be that in order to achieve the Euro's handling, a compromise had to be made which allowed more tramlining. *just guessing here*

Have you driven the Accord? The steering has no road feel but the turn-in response is very sharp and the handling is quite good. One could become accustomed to the over-boosted steering and 202 kW!

aaronng

14-04-2008, 08:13 AM

Have you driven the Accord? The steering has no road feel but the turn-in response is very sharp and the handling is quite good. One could become accustomed to the over-boosted steering and 202 kW!
I haven't driven the new one. I wonder how the new Euro handles then...

SPQR

14-04-2008, 08:30 PM

I haven't driven the new one. I wonder how the new Euro handles then...

aaronng, this is from my post in another thread:

I have just found what appears to be a recent review/road test of the 2009 Acura TSX at:

http://www.wikio.com/leisure/cars/ac...?wfid=51480361

Apparently, according (no pun intended) to one article, stability at speed has not improved with the car requiring constant corrective steering inputs. Another article says it was very good in foul weather.

http://www.wikio.com/leisure/cars/ac...?wfid=51480361

And some not so nice reviews at:

http://www.wikio.com/leisure/cars/ac...?wfid=51805757