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Cab325i/540i
11-19-2004, 11:32 AM
Hey folks, I haven't checked in for a while, but I had a question about the tires on our 540i. When we bought it, the P.O. had put 245/40r17 Dunlop SP 5000 (if memory serves) on some M3 LTW replica wheels. The wheels look sharp on the E34, but the tires are horrible, at least on the grooved/wintered roads in New England.

My wife really gets annoyed having to fight the steering so much when the car tramlines like it does. I know that 245 is too wide for this car, especially in the front, so what sizes and tires do you all recommend? We have a set of 225 Blizzaks for the winter (I should have bought 215 or 205, but I didn't, oh well), so I might want to put dedicated summer tires on the 17" wheels. My brother in law uses Bridgestone RE750s on his E34 M5, which is the tire I want to get for my E30. On the other hand, my wife doesn't exactly drive the snot out of the E34, and I autoX and track my E30, so all-seasons might be a better choice, that way I can use them in the inclement months when it's not blizzarding. I have Bridgestone RE950 all-seasons on my E30, which I like, but they're in a 195 width. Has anyone used these in a 225/45r17 or 235/45r17 on an E34? I'd really like a tire that doesn't make the steering so touchy. I'm leaning towards 225 in the front (well, the rear as well). Is that a good size?

Any other recommendations? Thanks!

Craig
11-19-2004, 12:18 PM
Lower profile tires tend to tramline more, if you really want to reduce the tramlining get rid of the 17" wheels and go to 16" (or 15" if they will fit the 540i brakes). Shoot for a 50 series tire too.

245/40 is a little too low, 245/45 is a better match to the original diameter. 225/45 will be horrible, don't even bother with those. If you must keep the 17" wheel a 225/50 is a better choice. The 225/45-17 is going to be almost 3/4 inch smaller in diameter and will have even less sidewall. A 225/50-17 is only about 1/3 of an inch smaller.

A 225/55-16 will be almost the same diameter as the stock size (at least what the stock size on a 535i is) and will tramline a lot less than those other sizes.

johnnyturbo2002
11-19-2004, 12:21 PM
what do you mean by "tramline"

Cab325i/540i
11-19-2004, 12:44 PM
Lower profile tires tend to tramline more, if you really want to reduce the tramlining get rid of the 17" wheels and go to 16" (or 15" if they will fit the 540i brakes). Shoot for a 50 series tire too.

245/40 is a little too low, 245/45 is a better match to the original diameter. 225/45 will be horrible, don't even bother with those. If you must keep the 17" wheel a 225/50 is a better choice. The 225/45-17 is going to be almost 3/4 inch smaller in diameter and will have even less sidewall. A 225/50-17 is only about 1/3 of an inch smaller.

A 225/55-16 will be almost the same diameter as the stock size (at least what the stock size on a 535i is) and will tramline a lot less than those other sizes.

Interesting. We've been debating tramlining for a couple of days on my E30 site. Some experience has shown the same style tires in 15" tramline more than in 16". The only other difference in the wheels was the offset. The experience shows that the lower offset, smaller diameter wheels tramline more. I thought that the higher sidewall might be providing more flex, exerting more force on the steering.

I had my wife check the tires, and they are 245/45, I didn't remember if they were 40 or 45 series. Anyway, the doorjamb recommends 235/45 as an option in 17", but I am thinking I might want to get down to a 225 width.

Tirerack says that 225/60r15 was OEM and recommends 235/45r17 as the +2 optional size. I don't need really wide tires for great lateral grip, I'd much rather have good steering feel, since this is my wife's biggest (really, only) complaint about the E34. I've thought about getting staggered sizes f/r as well, or just replacing the front tires and leaving the 245's on the rear. I don't absolutely have to keep the 17" wheels, but they look really great, and it would obviously be more expensive to replace them as opposed to not replacing them. I do not have the OE wheels. I have the snow tires mounted on Borbet Type H wheels in 15", but I'd rather keep those for just the snows.

Cab325i/540i
11-19-2004, 12:45 PM
what do you mean by "tramline"

Tramlining is when the steering of the car wanders because the tires are following the grooves in the road. It's a very annoying condition, and on this car in particular, with these tires, it's very bad, and sometimes the steering is true, but other times we have to fight the steering constantly because the tires want to pull wherever the road will take them.

johnnyturbo2002
11-19-2004, 01:29 PM
Thanks for the info, my wife just this morning said how the car is a little rough in the ride and I think that he tramlining is part of it, the roads here are torn up quite well. I have 235/45/17's on my car and when the time comes to change I would like something that doesn't make me have to fight the steering on the freeway so much ....Any thought's on tire rotation? Manual says that even though tires will wear a bit longer it isn't enough to warrent rotating tires since handeling can be changed. Obviously new to 540's so please forgive my ignorance if this has been discussed at length.
Cheers

Craig
11-19-2004, 01:30 PM
Interesting. We've been debating tramlining for a couple of days on my E30 site. Some experience has shown the same style tires in 15" tramline more than in 16". The only other difference in the wheels was the offset. The experience shows that the lower offset, smaller diameter wheels tramline more. I thought that the higher sidewall might be providing more flex, exerting more force on the steering.


Well, there are other things that can affect it, but if you are keeping the same wheels then the biggest contributor (at least in my experience) is the stiffness and size of the sidewall.

Some brands of tires are worse than others too, but the sidewall seems to be the thing most responsible for it.

Cab325i/540i
11-19-2004, 01:37 PM
Well, there are other things that can affect it, but if you are keeping the same wheels then the biggest contributor (at least in my experience) is the stiffness and size of the sidewall.

Some brands of tires are worse than others too, but the sidewall seems to be the thing most responsible for it.

Hmm. I always attributed it more to tread pattern than sidewall stiffness, which I attribute more to suspension feel.

Anyway, what size/brand tires do you use? Have you experimented much with different tread patterns and sizes? I like the Potenza RE950s I just put on the E30, but I don't know how they'd do in a larger size on the much heavier 540i.

Dash01
11-19-2004, 01:46 PM
Tramlining is when the steering of the car wanders because the tires are following the grooves in the road. It's a very annoying condition, and on this car in particular, with these tires, it's very bad, and sometimes the steering is true, but other times we have to fight the steering constantly because the tires want to pull wherever the road will take them.

Wouldn't that be a function of the interface between the texture of the road and the specific tread pattern of the tires, independent of the type of car?

In other words, if the grooves on the pavement mesh with grooves in the tires, the pavement will try and steer the car, regardless of what type of car it is.

Your thoughts?

Cab325i/540i
11-19-2004, 01:55 PM
Wouldn't that be a function of the interface between the texture of the road and the specific tread pattern of the tires, independent of the type of car?

In other words, if the grooves on the pavement mesh with grooves in the tires, the pavement will try and steer the car, regardless of what type of car it is.

Your thoughts?

Yes, I agree. However, if you ask someone who drives an E46 with Yokohama EVS 100 tires, they might tell you the tires tramline, and someone in another kind of car may not experience the same thing with the same tires. I don't understand exactly what makes certain tires tramline with certain cars, but one thing that seems to be common opinion is too wide tires on the front definitely doesn't help! Many cars (M3, M5 for example) come with wider rear tires from the factory, to help steering feel while also allowing more power to be put to the ground in the rear with the wider rubber.

I think it depends on how the tread pattern interacts with the road, but it also depends on how the steering geometry is set up on that car. If an outside edge tries to push the wheel in the wrong direction, and for example a wheel with a lower offset is on the car than it was designed with, then the outside edge might have a longer lever arm to force the steering with. Therefore the car was designed to resist certain forces coming from the tires, and if you change that force, the car is no longer set up to resist it. Does that make sense?

Qsilver7
11-19-2004, 02:00 PM
Hey folks, I haven't checked in for a while, but I had a question about the tires on our 540i. When we bought it, the P.O. had put 245/40r17 Dunlop SP 5000 (if memory serves) on some M3 LTW replica wheels. The wheels look sharp on the E34, but the tires are horrible, at least on the grooved/wintered roads in New England.

My wife really gets annoyed having to fight the steering so much when the car tramlines like it does. I know that 245 is too wide for this car, especially in the front, so what sizes and tires do you all recommend? We have a set of 225 Blizzaks for the winter (I should have bought 215 or 205, but I didn't, oh well), so I might want to put dedicated summer tires on the 17" wheels. My brother in law uses Bridgestone RE750s on his E34 M5, which is the tire I want to get for my E30. On the other hand, my wife doesn't exactly drive the snot out of the E34, and I autoX and track my E30, so all-seasons might be a better choice, that way I can use them in the inclement months when it's not blizzarding. I have Bridgestone RE950 all-seasons on my E30, which I like, but they're in a 195 width. Has anyone used these in a 225/45r17 or 235/45r17 on an E34? I'd really like a tire that doesn't make the steering so touchy. I'm leaning towards 225 in the front (well, the rear as well). Is that a good size?

Any other recommendations? Thanks!

I just mounted 17" Kumho ASX (all seasons) back in October and I like them a lot. They are quiet and have good grip in the wet & dry...we haven't had any snow yet so can't testify to their snow ability. (my dedicated 16" 225/55/16 Michelin Arctic Alpins will be going on after Thanksgiving ) I have no problems with any type of tramlining or fighting grooves in the road. Since my 525iT isn't a real a$$ hauler...I thought it a waste to mount high performance tires on her...so I went with all seasons (for spring/summer/fall) which can buy me time to switch over to the snow tires in case we get hit with an early snow in the fall...or a late snow fall in the spring. ;)

Your tramlining experience may be a combination of needing new tires and/or some front end suspension/steering parts replacement. (left/right/center tie rods, idler arm, upper control arms w/bushings, lower control arms, etc.)http://memimage.cardomain.net/member_images/1/web/433000-433999/433594_298_full.jpg

Cab325i/540i
11-19-2004, 02:13 PM
I just mounted 17" Kumho ASX (all seasons) back in October and I like them a lot. They are quiet and have good grip in the wet & dry...we haven't had any snow yet so can't testify to their snow ability. (my dedicated 16" 225/55/16 Michelin Arctic Alpins will be going on after Thanksgiving ) I have no problems with any type of tramlining or fighting grooves in the road. Since my 525iT isn't a real a$$ hauler...I thought it a waste to mount high performance tires on her...so I went with all seasons (for spring/summer/fall) which can buy me time to switch over to the snow tires in case we get hit with an early snow in the fall...or a late snow fall in the spring. ;)

Your tramlining experience may be a combination of needing new tires and/or some front end suspension/steering parts replacement. (left/right/center tie rods, idler arm, upper control arms w/bushings, lower control arms, etc

Thanks. The tires are very new, I have new lower CAs, new front shocks, and I know I need new upper CAs (those are the thrust arms, yes?). AFAIK, the tie rods and idler arm are all okay. The 540i can definitely haul, but it is my wife's car, and isn't used as a track car or anything, so I don't want to pour a lot of money into the tires for it, either. I'd much rather save the fun money for the E30!

Tiger
11-19-2004, 02:24 PM
I highly recommends Bridgestone RE7XX tires... I went from Nitto Extreme 555 to oldie Bridgestone RE730 that I got left over from my other car... What a difference! It went from rock hard to supple ride that even the biggest pothole doesn't jar my fillings out.

johnnyturbo2002
11-19-2004, 02:45 PM
are your wheels M on your wagon? I have the same and I like them but I am not sure if the are m wheels

Cab325i/540i
11-19-2004, 03:11 PM
are your wheels M on your wagon? I have the same and I like them but I am not sure if the are m wheels

Those look like Style 23 to me. My wheels are a replica of Style 24 (made with the right offset for the E34.

http://www.kalach.easynet.be/bmw_wheels.htm

johnnyturbo2002
11-19-2004, 04:01 PM
lots o wheels

SharkmanBMW
11-19-2004, 06:05 PM
i have found as long as front is narrower than rear - it is less a worry than having the same all round.
the wider rear seems to help absorb road sloppiness and forces you to make more steering input to get a certain result.
if the tires were all the same, less steering input is required for the same result.
that is why M5 and the real power cars are wider in the rear, it is a handling/steering input issue.
i read a great article somewhere recently about this , i will look for it.

riot
11-19-2004, 06:43 PM
I'm about to purchase new rims and tires for my car. I'm going to go with an 18" rim and low profile tires. So What size tires should I get ?

DueyT
11-19-2004, 07:00 PM
Cab, I have 235/45-17 front, 255/40-17 rear and don't have any noticable tramlining to speak of. The wheels are 8"x17" front and 9"x17"...other folks with four 8"x17" wheels usually just run 235/45-17 on all corners.

p.s. in the winter I run 205/65-15's...

Cheers,
Duey

http://www3.sympatico.ca/dnatown/540strtR.jpg

SharkmanBMW
11-20-2004, 02:33 PM
ditto , wider in rear than in front is better!
i have found as long as front is narrower than rear - it is less a worry than having the same all round.
the wider rear seems to help absorb road sloppiness and forces you to make more steering input to get a certain result.
if the tires were all the same, less steering input is required for the same result.
that is why M5 and the real power cars are wider in the rear, it is a handling/steering input issue.
i read a great article somewhere recently about this , i will look for it.

Qsilver7
11-20-2004, 09:14 PM
are your wheels M on your wagon? I have the same and I like them but I am not sure if the are m wheels

Otherwise known as AT Italia Type 5 sold by www.TireRack.com. :D

charlie
11-22-2004, 03:58 PM
If you are getting the 18" staggered (M parallels) you want to go with 235/40 on the front and 265/35 on the rear. that is if you get the 9.5" wheels in the back. these fit and look good!


I'm about to purchase new rims and tires for my car. I'm going to go with an 18" rim and low profile tires. So What size tires should I get ?