Magnesium Alloy Frames?

[montyrider]

These are the only benefits of using magnesium alloy frames i could come up with!

Light weight

Low density (two thirds that of aluminium!)

Good high temperature mechanical properties e.g Gear box castings

Good corrosion resistance

Which sums up theyre only good for about a few months use! a DOB frame costs £230 and weighs 1.4 kg which is impressive but i don't see the point in sacrificing all that weight who on here owns one and can say they've found it better than a aluminium frame e.g U6 i rid a magnesium one and found it flexy and to light no resistance in it and no feeling!

Aluminum is significantly cheaper pound for pound....and stronger an echo pure is £230 and weighs 1.8 kg

What are peoples thought on this magnesium obsession? i just cant see why anyone would buy a magnesium frame am i just being stupid?

[N.Wood]

I bought one.

If you look at people who are obsessed with weight, 400g is alot to them.

You've seen them all cutiing bits out of their frames, wheels, hubs, tensioners, etc.

Some people like the springy feeling, i guess.

I wouldn't say its an obsession, theres what... 1 mag frame out? Gotta try new things or we'd be stuck on xc bikes.

[montyrider]

I bought one.

If you look at people who are obsessed with weight, 400g is alot to them.

You've seen them all cutiing bits out of their frames, wheels, hubs, tensioners, etc.

Some people like the springy feeling, i guess.

I wouldn't say its an obsession, theres what... 1 mag frame out? Gotta try new things or we'd be stuck on xc bikes.

Ha Ha i see what your saying....thought this would be a good topic for discussion.....xc bikes are in the space age carbon fibre zone! ) a mate of mine was on some magnesium trials shop or sumthin and everything was magnesium thay had heeps of magnesium frames and parts....and bragging about weight loss. but each to their own as they say i can see a bemefit in losing 400g it is weight loss nearly have a kg but some u6 frames weigh less and cost more but would'nt it a better investment in the long run to pay that bit more for strength?

[walker]

Ive heard from a road biker that in the past, magnesium frames havnt really taken off because they age quickly, and when fatigue sets in they become more flexible, which for road biking is no good, it just makes the frame less energy efficient. so the same would be true for trials bikes. I ride a steel frame, so that is probably as rigid as your going to get. i think that feeling and rigidity are very important in trials riding.

It will be interesting to see how these frames last, and i dont know if they will have been tested for long enough. But it seems that these days people are happy getting a new frame every 6 months or less, but will they even last that long???

Andrew

[montyrider]

I cant remember where i heard this....but say if you were gapping rails (on a magnesium frame) and slid off and your downtube hit it hard instead of the material just denting it'd develop a stress mark as well or worse split! on an aluminium or steel frame you'd get a weee little dent! anyone heard the same!

Magnesium is'nt to keen on being flexed a lot think of how you can keeping bending a paper clip and it gets softer and easier bend? but on a much larger scale.....if anyone has some long term experience with a mag frame it'd be interesting to know their thoughts?

Edited February 9, 2008 by montyrider

[ZeroMatt]

To be honest most alu is pretty stiff and quite prone to complete failure rather than just bending like steels so is not entirely disimilar to mag alloys. Can't say much about mag as I don't know very much about the various alloys but it will most likely play a part in the progression of trials componentry. Which is all good in my eyes.

Edited February 9, 2008 by ZeroMatt

[montyrider]

Yeah i defenitly agree steel has a bit more give when it comes to stress as it'll bend before it snaps unlike mag or alu which can be unpredictable and just snap before it will bend!

[Gandalf the Yellow]

i got 1 coming my way. not liking the sound of things but meh

mag is brittle so yes like alu alloy frame it'll snap. and most probably have stress marks where its been fatigued. but you can't really tell till someone's actually tested 1 properly for trials.

its too new. but we need new things to keep us evolving other bikes will look and ride the same for the coming years.

steve

[Bionic Balls]

i've only heard good things about magnesium alloys...people love 'em! gonna make it big one day..

[Shaun H]

To be honest most alu frames are pretty stiff and quite prone to complete failure rather than just bending like steel frames so is not entirely disimilar to mag alloys. Can't say much about mag as I don't know very much about the various alloys but it will most likely play a part in the progression of trials componentry. Which is all good in my eyes.

Aren't you an engineer? Aluminium stiffer than steel? Should know better.

It's all in the way the material is used. I.E. tubing thickness and guage.

The stuff the industry refers to as "magnesium" is really mostly aluminium. Don't specifically know much about it so I won't try and blag it haha

[Muel]

I bought one.

If you look at people who are obsessed with weight, 400g is alot to them.

You've seen them all cutiing bits out of their frames, wheels, hubs, tensioners, etc.

Some people like the springy feeling, i guess.

I wouldn't say its an obsession, theres what... 1 mag frame out? Gotta try new things or we'd be stuck on xc bikes.

It's an awful lot! I've come up with a list that would shave about 400-500g from my bike, and it would cost £400.

I may get round to spending £30 and saving 200g, but meh, it falls into the "light enough" catagory. I want a bike I can ride in comps and bash some street with, so it has to be around 9kg and stiff and strong as f**k, and this bike fills the criteria, so I'll leave it alone for a while.

But yes, I think these DOB frames are very interesting, but I couldn't be doing with the flexiness, the reason I have Echo's is they are fairly light, (1.7kg), but very stiff and strong, and cheap.

I'm putting my Echo forks back on now, the carbons are very nice, but I want to save them for comps and they are a bit flexy for front wheel moves.

[ZeroMatt]

Aren't you an engineer? Aluminium stiffer than steel? Should know better.

It's all in the way the material is used. I.E. tubing thickness and guage.

The stuff the industry refers to as "magnesium" is really mostly aluminium. Don't specifically know much about it so I won't try and blag it haha

Thanks for adding the "frames" I totally minced my words trying to explain it, hence why I'm doing an engineering course rather than English haha.

But yeah with better knowledge as to how the material fares when used as a trials frame you can engineer the frames to make better advantage of its properties.

[Krisboats]

My "magnesium" pedals are nicer than my ally ones and they hold up alright. The ally pedals seemed to get scratches just as easily and neither have broken yet so strength doesn't seem to be an issue. The magnesiums are a lot lighter though which can only be a good thing. I know it isn't a frame comparison but if the frames can perform as well as the pedals then thats great.

I personally think theres a few noticeably flexy frames available, i think monty's are too flexible but people still buy them.

I don't think many people can give an honest and substantial opinion though as they're too new to the mainstream and while we can all have our theories and "i heard that magnesiums frames are....." scenarios, they don't really mean shit without trying them first hand.

[Greetings]

It's not an obsession, I doubt more than 2% of the riders out there have a magnalium frame or would consider buying one. Innovation is a good thing. 15 years ago, people probably had the same attitude towards aluminum frames saying they're so much more expensive than steel, much weaker and only 0,5kg lighter. Throughout that period of time, the material aluminum frames are made from was developed and now it's quite rare to see a well engineered U6 frame crack. Even so, manufacturers are introducing Ultra6 Pro which is going to be even stronger. Same applies to steel, there's one being engineered that will have a higher strength to weight ratio than titanium. I can't see magnalium being different, it's a fairly new alloy comparing to the other two and I'm sure it will be improved.

There are as many types of riding styles out there, as there are frames. If you're a smooth rider or a comp rider and don't mind something that flexes, you'll be well off with one of these.

[Jason222]

I've got a DOB frame and my friend has a Echo Pure frame(new one). The DOB frame's rear end flexes less than the echo does. The tubing is also much thicker, and the frame is so much lighter....

[Muel]

I've got a DOB frame and my friend has a Echo Pure frame(new one). The DOB frame's rear end flexes less than the echo does. The tubing is also much thicker, and the frame is so much lighter....

If it cracks, give us some details dude!

Why, WHY couldn't they have brought it out as a long frame, like a 1020. 985 is just gay.

I want my Echo, but made out of this Magnalium stuff.

[Jason222]

WHY couldn't they have brought it out as a long frame, like a 1020. 985 is just gay.

It's short because it has a mega short rear end, and a sharp head angle...would probably be like 1005 or something with regular length chainstays. Check on tarty, the front end length is the same as the other frames...

[Muel]

Hmm, to be honest I don't think it's a good idea any more, I put my Dad onto it and he's been chatting to a few people, the sort of magnesium alloy the Dob frames are made of will PROBABLY, be a cheap variety, because the frames themselves are so cheap. For £229, you can't afford a good quality magnesium alloy, as it costs more than 6061 aluminium.

Therefore, we can assume it is made out of a cheaper type of Magnesium alloy, which is lighter, but weaker, so I can't see them lasting very long.

They may prove me wrong, but I'd imagine the life span would be quite short compared to a Deng frame.

[N.Wood]

Hmm, to be honest I don't think it's a good idea any more, I put my Dad onto it and he's been chatting to a few people, the sort of magnesium alloy the Dob frames are made of will PROBABLY, be a cheap variety, because the frames themselves are so cheap. For £229, you can't afford a good quality magnesium alloy, as it costs more than 6061 aluminium.

Therefore, we can assume it is made out of a cheaper type of Magnesium alloy, which is lighter, but weaker, so I can't see them lasting very long.

They may prove me wrong, but I'd imagine the life span would be quite short compared to a Deng frame.

If you ride it like a twat (read: basher) then yeah, you're probably right.

They're not designed for dropping off buildings like a sack of shit like alot of Deng riders like to do, they're designed for comp riding where light weight is more important over strength.

This isn't to say they're gonna fall apart after a comp season, but if you treat anythign with care it can last forever...

[Muel]

Good points there Nick, it will be interesting to see how they work out.

[Paul@Deltabikes]

The whole magnesium frame thing was done with MTBs in the early/mid nineties and then trailed off. I think the downsides out weight the positives but I am happy to be proved wrong I can't see many other manufacturers following suit and adding magnesium frames to their product line ups.

[Tomm]

if you treat anythign with care it can last forever...

The only way a trials bike will last forever is if you never ride it...

I don't know the relative cost of magnesium vs aluminium BUT I do know that very little magnesium will be used - it's still an aluminium frame, there just happens to be a trace of magnesium in it.

Also, since frames from the far easy only cost £30 ish a piece to make, the difference in cost between manufacturing an alu frame and a mag one doesn't necessarily have to make a big difference to the price you see in the shops.

[eskimo]

400 grams is almost a lb. Which is alot of weight to save. I'd be pleased with any setup that saved that much weight. 100 grams is even easily noticable.

It's also obvious that they won't last but some people don't ride that hard! Let alone much at all. You could almost argue the same with the Monty TI or even an actual TI frame.

Mag pedals have the same principle as well yet people are all over the MG1s. The pins rip out straight away if your heavy.

It all depends if people are ready to split with their cash for a light & weak frame. But some people earn more than enough to not even give a damn about breaking it, so why not? (that doesn't include me though )

[Shaun H]

The only way a trials bike will last forever is if you never ride it...

I don't know the relative cost of magnesium vs aluminium BUT I do know that very little magnesium will be used - it's still an aluminium frame, there just happens to be a trace of magnesium in it.

Also, since frames from the far easy only cost £30 ish a piece to make, the difference in cost between manufacturing an alu frame and a mag one doesn't necessarily have to make a big difference to the price you see in the shops.

There's alot more than just a trace of magnesium. I hear it's more around 40%. If it was just a trace the alloy would weigh more or less the same as any aluminium alloy.

I imagine magnesium frames may be more expensive to produce due to the precautions needed around any dust or swarf (it's actually quite flammable in this state, like pure magnesium) and it may need specialised welding equipment although I'm not sure on that one. Also as mentioned earlier the alloy is more expensive than standard aluminium alloys (possibly more because of lack of demand than anything else).

However they're a fair bit lighter so shipping will be cheaper.

[t33zr]

my friends DOB frame cracked after a week in 2 different spots.... after 2 week it snapped....