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-   -   DYMAG Wheels... Any downsides? (https://rennlist.com/forums/wheel-and-tire-forum/533249-dymag-wheels-any-downsides.html)

rijowysock 11-03-2009 04:09 AM

DYMAG Wheels... Any downsides?
 
Looking into a Set of DYMAG wheels... im not a scientist nor an engineer so im asking the people that would know.. any downsides to DYMAG's for daily use?

ive heard people say magnesium wheels have expiration dates (friend of mine races daytona prototypes and i asked once why so many wheels sitting around and he said something about the magnesium gets brittle)?

the carbon is more rigid and not malleable like aluminum but have people had problems w/ dymags in past?


basically.. in a nut shell, price aside.. would DYMAG's be good for a daily driver or am i smoking crack and getting in over my head with wheels that will expire and be to brittle for the road?

-riley

Boinkus44 11-03-2009 11:50 PM

I think your friend is right about the magnesium. I've got Dymags and have used them almost exclusively on the track, and have just discovered serious stress cracks in the magnesium spokes. The carbon fiber has held up well structurally but the finish has deteriorated. They can be refurbished but it's not cheap:eek:.

I loved the lightness, and after 50 odd track days, the Dymags are toast and need major work. Not sure how that translates into street miles, but they definitely have a finite life. Not yet decided if I'm going to spend the $5K+ to refurbish. Love the lightness though. Expensive habit....... Very noticeable on the 6GT3, and the Dymags make it a better car. YMMV


There's a recent thread here on the Dymag subject with pics. Don't know how to attach the link but it should be easy to find.

deputydog95 11-04-2009 10:48 PM

http://farm4.static.flickr.com/3048/...3e20b541_o.jpg

mdrums 11-04-2009 11:21 PM

Riley...DON'T DO IT! Keep the Works or Volks...better in my book!

RJFabCab 11-04-2009 11:35 PM


Originally Posted by deputydog95 (Post 7047975)

Deputy,

What's the story on that wheel failure? Can you link me to a thread? RE the Dymag failure... that pic sure makes me appreciate all the 'nuts and bolts' in all my aluminum rims! :eek:

To riley,

I'd pass on magnesium wheels for the street. Pitting and corrosion issues with respect to the elements are reason enough to stay away from them.

Get a quality set of forged aluminum wheels... designed with the 'street' in mind so that you don't bend the outer rim on your first pot hole.

Save the trick light weight set for your track days... ;)

RollingArt 11-04-2009 11:50 PM

Wow.

Really makes you want to go out and get a set of these Dymags.

Plus the carbon rim will likely break when it hits a good pothole.

Save yourself the grief Riley. Take a pass.



Phil

TB993tt 11-05-2009 11:43 AM

Since begining of this year the centres have been made out of magnalium, an a proprietry Dymag alloy of Aluminium and magnesium. They say this alloy will not crack like magnesium.
Mine are used as a daily driver, pot holes, 200mph etc and are holding together still. The finish on the CF around the rim is cracking cosmetically but apart from that they are an awesome bit of kit and make the car "dance".

The bad news is I believe Dymag has called in the reciever on the old company. My source said there was a potential litigation problem with Konigsegg (is that the right company ? the one who used the wheels as OEM ?) which they want to "put to bed".
Also interestingly the recievers have said that the company is not viable for the prices they were charging fo rthe CF wheels and the prices would have to go up 35% to make them viable..... this is not surprising, I couldn't believe how cheap mine were when one sees the quality and materials.

PS That picture of the cracked centres has been doing the rounds forever and is of a heavily tracked wheel with mag centres - how many BBS mags suffered the same fate ?

Boinkus44 11-05-2009 05:18 PM

4 Attachment(s)
Here's the link to my recent thread on this very subject:

https://rennlist.com/forums/wheel-an...th-dymags.html


And here's some pics of my Dymag experience :(. Needless to say they're retired and not being repaired.

rijowysock 11-05-2009 05:24 PM

ouch, passing..

hmmm. whats next..

deputydog95 11-05-2009 07:19 PM

I just pulled the trigger on those new OZ 18's. Allegrita or something that I can't pronounce or spell :)

Boinkus44 11-05-2009 10:04 PM


Originally Posted by deputydog95 (Post 7050579)
I just pulled the trigger on those new OZ 18's. Allegrita or something that I can't pronounce or spell :)

Since the great Dymag experiment is over for me, I'm now in the market for track wheels and came across the OZ Alleggerita HLT's as well. Look great, reasonably light and good price. I could buy 3 sets for the cost of refurbishing the Dymags. If they're track worthy, I'll probably get a set. Otherwise CCW's. Let me know how the OZ's stand up.

RJFabCab 11-05-2009 10:12 PM


Originally Posted by TB993tt (Post 7049056)
PS That picture of the cracked centres has been doing the rounds forever and is of a heavily tracked wheel with mag centres - how many BBS mags suffered the same fate ?

I really don't keep up with Dymag's progress and evolution, so I am not that familiar with their construction. From Dymag's site, it looks like the current wheels have the centers bolted to the carbon rims.

Race rims under duress are at risk of failure. What concerned me about the Dymag failure pic was that the center separated from the carbon rim... in addition to cracking at the spokes. It didn't appear that the wheel pictured had any holes in the carbon rim to receive bolt hardware.

Were the centers bolted to the rim? Did the bolts shear?

deputydog95 11-05-2009 11:04 PM


Originally Posted by Boinkus44 (Post 7051171)
Since the great Dymag experiment is over for me, I'm now in the market for track wheels and came across the OZ Alleggerita HLT's as well. Look great, reasonably light and good price. I could buy 3 sets for the cost of refurbishing the Dymags. If they're track worthy, I'll probably get a set. Otherwise CCW's. Let me know how the OZ's stand up.

There's a GT3 at my shop that's been running the hell out of the OZ's. There's another car at the shop that is running the OZ HLT wheel (Superlegarra or something like that) at the track as well. No problems (knock on wood). My OZ's came in today. They look awesome and are super light (21 rear and 18 front). Not to mention the price is reasonable.

I can't wait to mount them up. I'm running Daytona next weekend so I'm really excited to see how the new wheels with the MPSC's hold up. I've been tracking on some 3 piece cargraphic wheels (19's) with some crappy Dunlop Sport tires. This should be a huge step up.

mdrums 11-05-2009 11:07 PM


Originally Posted by rijowysock (Post 7050186)
ouch, passing..

hmmm. whats next..

BBS E88....dream wheel!

TB993tt 11-13-2009 10:59 AM


Originally Posted by RJFabCab (Post 7051196)
I really don't keep up with Dymag's progress and evolution, so I am not that familiar with their construction. From Dymag's site, it looks like the current wheels have the centers bolted to the carbon rims.

Race rims under duress are at risk of failure. What concerned me about the Dymag failure pic was that the center separated from the carbon rim... in addition to cracking at the spokes. It didn't appear that the wheel pictured had any holes in the carbon rim to receive bolt hardware.

Were the centers bolted to the rim? Did the bolts shear?

The centres are bolted to the rims yes and there are holes in the carbon. The pic of the disintigrated centres and the ones above are surely what magnesium wheels do eventually, the bolts didn't shear, no problem there ?

I have cracked about 4 magnesium BBSs in the past, the Dymag Magnesium centred wheels will be no different.

Like I said the latest Dymags are not made from Magnesium (just like the latest BBS race E88s are not made from magnesium anymore) so they won't crack like in the pics...... It amazes me how many people look at the pictures of the cracked Dymags and instantly "write them off" as a choice - can these people not understand that that is what magnesium does, people do not realise the history Dymag have of making wheels - in the UK the have been involved in motorsport for decades and have made F1 wheels and make for heavy industrial application like trains !!
TBH I am quite happy that many people are put off since it keeps the wheels ultra exclusive but then the new pricing will aid in that department also !

cobalt 11-16-2009 04:42 PM


Originally Posted by TB993tt (Post 7070368)
The centres are bolted to the rims yes and there are holes in the carbon. The pic of the disintigrated centres and the ones above are surely what magnesium wheels do eventually, the bolts didn't shear, no problem there ?

I have cracked about 4 magnesium BBSs in the past, the Dymag Magnesium centred wheels will be no different.

Like I said the latest Dymags are not made from Magnesium (just like the latest BBS race E88s are not made from magnesium anymore) so they won't crack like in the pics...... It amazes me how many people look at the pictures of the cracked Dymags and instantly "write them off" as a choice - can these people not understand that that is what magnesium does, people do not realise the history Dymag have of making wheels - in the UK the have been involved in motorsport for decades and have made F1 wheels and make for heavy industrial application like trains !!
TBH I am quite happy that many people are put off since it keeps the wheels ultra exclusive but then the new pricing will aid in that department also !

I manufacture magnesium castings for a living. Incredible material. Alloy used for wheels plays a critical role along with the design, casting process and heat treatment cycles. Most of your F1 wheels are made of a zirconium based rare earth alloy called ZE41AT5, very expensive the additive runs around $15 a pound and requires roughly a 17% addition to quantity poured. It has great yield strength but not much tensile strength. All Magnesium alloys are susceptible to impact damage, and corrosion from the elements. It is easily used in F1 where cost is less important than weight savings and wheels are expendable.

IMO when I first saw these wheels I though the spoke design was not adequate for the loads required. I guess I was correct in my assumption. The biggest issue with magnesium is that no matter how well the processing was done you can only work to minimum requirements and magnesium can achieve strengths similar to cast aluminum more often than not it falls short.

I will say that based on what I have seen over the years the fracture in the picture above is more likely a case of improper heat dissipation. The material looks as though it had been annealed from prolonged exposure to high temperatures exceeding 500 degrees. The shinny exposed metallic look to the broken areas is a giveaway. If this material was properly heat treated and in sound condition the broken areas would look a creamy mat color and not shinny silver. This might also be a result of the CF not being able to transfer the heat across the barrel of the wheel. Although thicker spokes would have added little extra unsprung weight and given far great strength to the design.

As far as proprietary alloys there aren't many configurations that haven't been tried. One very popular alloy many years ago was called almag 35 more of a high concentration magnesium based aluminum alloy very strong and stable although it is heavier than your average mag alloys.

deputydog95 11-17-2009 09:00 AM


Originally Posted by TB993tt (Post 7070368)
The centres are bolted to the rims yes and there are holes in the carbon. The pic of the disintigrated centres and the ones above are surely what magnesium wheels do eventually, the bolts didn't shear, no problem there ?

I have cracked about 4 magnesium BBSs in the past, the Dymag Magnesium centred wheels will be no different.

Like I said the latest Dymags are not made from Magnesium (just like the latest BBS race E88s are not made from magnesium anymore) so they won't crack like in the pics...... It amazes me how many people look at the pictures of the cracked Dymags and instantly "write them off" as a choice - can these people not understand that that is what magnesium does, people do not realise the history Dymag have of making wheels - in the UK the have been involved in motorsport for decades and have made F1 wheels and make for heavy industrial application like trains !!
TBH I am quite happy that many people are put off since it keeps the wheels ultra exclusive but then the new pricing will aid in that department also !

If that's what magnesium "does", then why use it? Seriously? Unless you're changing the wheels out for every event and throwing the old ones away or sending them back to the factory for inspection, why would anyone want to use a wheel that they know is going to crack at some point? I would rather have 10% more weight and the confidence that the wheel probably isn't going to shatter... Although I guess that's why they're not using magnesium anymore. What can't figure out is why you would keeping using magnesium after you kept breaking wheels... One is a defect, two is a problem. Time to dump the set.

deputydog95 11-17-2009 09:01 AM


Originally Posted by Boinkus44 (Post 7051171)
Since the great Dymag experiment is over for me, I'm now in the market for track wheels and came across the OZ Alleggerita HLT's as well. Look great, reasonably light and good price. I could buy 3 sets for the cost of refurbishing the Dymags. If they're track worthy, I'll probably get a set. Otherwise CCW's. Let me know how the OZ's stand up.

I just came back from running Daytona this past weekend. The OZ's with pilot cup's were great! The feel from my 19" cargraphics with street tires to the OZ's was a tremendous improvement.

cobalt 11-17-2009 09:46 AM


Originally Posted by deputydog95 (Post 7076585)
If that's what magnesium "does", then why use it? Seriously? Unless you're changing the wheels out for every event and throwing the old ones away or sending them back to the factory for inspection, why would anyone want to use a wheel that they know is going to crack at some point? I would rather have 10% more weight and the confidence that the wheel probably isn't going to shatter... Although I guess that's why they're not using magnesium anymore. What can't figure out is why you would keeping using magnesium after you kept breaking wheels... One is a defect, two is a problem. Time to dump the set.

Magnesium is best suited for racing where every ounce makes a difference. For the weekend warrior I agree it doesn't make much sense. Although aluminum will do the same exact thing if temperatures are allowed to get to high. Annealing any metal will cause it to loose its strength. ie world trade center collapse. Sorry for the example but it makes the point. I have seen aluminum wheels fail just the same because they were allowed to get too hot for too long. Proper brake venting heat dissipation is critical. Design has a lot to do with it also.

deputydog95 11-17-2009 09:49 AM

I'm totally with you on those points. Although I'm sure F1 teams have dozens of sets of wheels to work with. For the DE guy or street driver, using something that will probably fail doesn't make sense. Unless you're being paid to race, a few extra ounces won't matter :)

ricster 11-17-2009 10:01 AM

" For the DE guy or street driver, using something that will probably fail doesn't make sense. Unless you're being paid to race, a few extra ounces won't matter"

Well said!! I have a friend who worked for Flying Lizard race team and he told me they use BBS wheels because they are the best.....so if its good enough for them its good enough for me...and you.

I recommend BBS LM wheels for your car.

cobalt 11-17-2009 10:10 AM


Originally Posted by deputydog95 (Post 7076654)
I'm totally with you on those points. Although I'm sure F1 teams have dozens of sets of wheels to work with. For the DE guy or street driver, using something that will probably fail doesn't make sense. Unless you're being paid to race, a few extra ounces won't matter :)

F1 teams also inspect everything thoroughly before and after each use. The old 917/935 wheels were mag alloy. I have a friend with a Jagermeister 935 and he had his original wheels refinished. They were quite solid and held up well because of the design. Far more strength in the spokes thickness to the barrel and much better brake cooling.

I would not discount mag for AX or DE. I would recommend inspecting your wheels every chance you get but I recommend that for any wheel mag or alum. There are varying grades in quality of alum wheels also. Low profile tires and stiff sidewalls can cause factory wheels to fracture just from impact and these are high strength aluminum. Mnay people use the 993TT hollow spoke wheels for DE and they are notorious for fracturing.

I have many friends that own vintage race cars and take them to historic races. More times than not the mag parts are replaced with aluminum copies. Although these guys are out there for fun and bragging rights where safety takes priority over weight.

TB993tt 11-22-2009 12:37 PM


Originally Posted by deputydog95 (Post 7076585)
What can't figure out is why you would keeping using magnesium after you kept breaking wheels... One is a defect, two is a problem. Time to dump the set.

That is a very good question :D

The mag centerd wheels were Porsche993GT2 Speedlines, the ones with the 5 spoke mag centres. I bought a set second hand for my 993tt which I adorned with GT2 arches. I didn't really know anything about cracking magnesium back then and soon learned.
I loved the look and since no one else made anything which looked the same I persevered..... It was the rears which cracked, one really badly and potentially dangerously. I ended up leaving them in my garage for most of the time and used 996tt alloys instead. Someone kindly alleviated the problem by breaking into my garage and stealing them - I didn't really shed any tears, they shouldn't be used on road cars really without the aformentioned inspections/xrays etc and were/are an accident waiting to happen.
I hope the new Dymag alloy holds up !

deputydog95 11-23-2009 08:20 AM

Isn't Fiksi out of business now? I know someone with someone wheels that were sent in for repair and now no one has been answering the phones for a couple weeks.

Where do you get a low profile jack? It is a such a pain in the ass to get my car jacked up as I have to drive up on a couple small sections of 2x4 and then race to jack the car up before they've been sitting on those narrow 2x4's for too long.

rennschnell 12-03-2009 02:20 AM

I'm a little late to this post, but didn't BBS switch from a magnesium center section to an aluminum forged center on there modular race wheels about 5yrs. ago?

Also, how are the CCW modular wheels? I see/hear that alot of folks are using them mainly due to price, but they look pretty rough. I've seen a few up close and the bolts look like grade 8 from the local Homedepot with nylon locking nuts. On the CCW website they have a video showing you how to do your own wheel repair at home.

http://www.ccwheel.com/files/technical.php

Two things that concern me are, the tech is using a 3/8" drive impact gun on full blast to run down the nuts and uses his finger to smear the silicone seal. Doesn't seam like a very high tech wheel for a Porsche. I've seen the guys from BBS and Fikse at the Daytona 24hr years ago replacing wheel parts and both used hand tools. Both used a 12 point bolt, looked like an aerospace type. I guess when you watch a video on how they hand build a Porsche Motorsport, AMG or Katech engine you would expect the same materials, care and similar modern technology to be used on your aftermarket wheels. If you paid an extra $2k for titanium connecting rods, but then bought the cheapest aftermarket wheels available for track use, would you expect them to perform equally as your engine with the titanium rods?

Just my two cents here, great discussion about wheels. Funny you read about wheels on other forums and it's all about the latest color or chrome the wheel company has available.

cobalt 12-03-2009 10:07 AM


Originally Posted by rennschnell (Post 7114333)

http://www.ccwheel.com/files/technical.php

Two things that concern me are, the tech is using a 3/8" drive impact gun on full blast to run down the nuts and uses his finger to smear the silicone seal. Doesn't seam like a very high tech wheel for a Porsche. I've seen the guys from BBS and Fikse at the Daytona 24hr years ago replacing wheel parts and both used hand tools. Both used a 12 point bolt, looked like an aerospace type. I guess when you watch a video on how they hand build a Porsche Motorsport, AMG or Katech engine you would expect the same materials, care and similar modern technology to be used on your aftermarket wheels. If you paid an extra $2k for titanium connecting rods, but then bought the cheapest aftermarket wheels available for track use, would you expect them to perform equally as your engine with the titanium rods?

Interesting link thanks for posting.

I wouldn't be so concerned about the impact driver. I would assume it is set to the appropriate torque and is designed or set up for its intended purpose and supplies specified torque with each pull of the trigger. I don't necessarily agree with their approach regarding the time needed for the silicone to set and the way they torque the bolts. I would still stagger bolt torquing after the 4 are tightened and I am surprised to see they are using Silicone #II vs Silicone # I or more like other brands that use a silicone based gasket.

altonj 01-03-2010 12:41 AM

Ok,

here is how to do it....

Assemble the wheel torquing each fastener in a criss-cross patern to its specified value. Be it a 6mm BBS fastener or a 1/4 inch or 5/16 fastener. The use a silicone "adhesive" and not a silicone "sealant" to fill the valley and seal the wheel. We have had excellent success with the products from Dow and good success with the products from Loctite.

DO NOT use air tools. The torque values for the small fasteners are very low 12-14lb feet depending on where you source your fastener and its nominal diameter.

Cheers

333pg333 01-05-2010 12:53 AM

Out of curiosity, what are Dymag saying about all this???

TripleM 01-07-2010 04:21 AM

I like Carbon products for body panels but not for wheels, cant justify the existence of it really..
Forged LW Alloy is the furtherst I'd go..

Griswald 01-07-2010 10:57 PM

I'll say up front that there are many, many great wheels out there.

I've run CCW's for a number of years for track and AutoX. I've NEVER had a problem - period. As for looking rough, well, all of them I've seen look good to me. Value for the money I'll put them up against anything. Those of us who have raced Vipers and Vettes as well as PCars are well familiar with them. Do I sometimes run something else on my street car that is 3 piece, color matched, really, really 'pretty' etc. - sure. But for hard core use I like the CCW's - and even for street use.

Understand please, I'm no lapdancer and have no vested interest in CCW but IMHO they make a great product for the money.

iLLM3 01-07-2010 11:59 PM

Great info in this thread, thanks everyone for sharing!

Guns951 01-12-2010 04:06 AM

Just as an odd point but its about design and execution with materials. My magnesium centered wheels are 33 years old that were raced and beat on in the glory days of IMSA on a 935. Now they're on street duty with my car and after quite a few miles and being beat on they're still uncracked and holding up.

I know its apples to oranges but perhaps a better design with a slightly meatier tire (sidewall) would go a long ways in the longevity of these wheels.

gt2urbo 01-15-2010 03:36 AM

are dymags still being made? i was told by a wheel place that they they went out of business. i had em on my 07 tt and love em. now i want the cf40 HRE/dyamags for my gt2. thanks in advance

Bob Rouleau 01-15-2010 09:14 AM

Just a note - Fikse is back in business. They were bought by Kodiak. Now in production with parts and service. Nice to hear since they are very good wheels.
In my book the top brands are (in no special order) BBS, Fikse and OZ.


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