Steel vs Aluminum

Discussion in 'General Questions' started by Ozzie, Apr 6, 2008.

  1. Ozzie

    Ozzie New Member

    I was talking to a guy in a bike store and he stressed the dangers of putting a motor on an aluminum frame. He says it wont stand up to the vibrations of a motor and that I should go with an old-school steel frame. What do you experienced people have to say on the matter?

    The guy in the store is a "pedal purist" and didnt want to talk to much about Motored bikes but was smart enough to recognise a potential customer and was moderatly helpful with some questions I asked him.
    Last edited: Apr 6, 2008

  2. fetor56

    fetor56 Guest

    Tell the guy in the bike store he's talking out of his arse.
  3. fastboy9

    fastboy9 Member

    I've got an aluminium mountain bike and have modded my engine, and do most of riding off road on dirt tracks, no problems yet .......... hopefully
  4. There are those here that believe that especially when it comes to drilling into an aluminum frame. But I think as long as it's put together right,it shouldn't pose much of a problem.
    I would take an aluminum frame over a steel frame over 20 years old no known history. But I would take a steel frame newer that 20 years old with a relatively known history over an aluminum frame.
  5. graucho

    graucho Active Member

    Humf, "aluminum frame strong" (pounds on chest) Lo torque, 35 mph max speed, no problem. If you go off road, taking jumps, banging up and down curbs. Yes problem.
  6. Demosthenese

    Demosthenese Guest

    even so, if you don't drill your aluminum frame, the bolts on the HT are still prbly more likely to break then the frame. If you have front shocks that are super cheap they could prbly go as well if you bang it around too much. Spokes can break, chains can break, sprockets can shear off bolts, heads can blow, carbs can fail... i don't know, i haven't read here about a frame failure yet, i don't think, except for maybe talk about the Moon Dogs, which are not really comparable to anything else.
    A badly welded steel frame will certainly not be better then an expensive aluminum one, but everything else being equal, as long as you're not pedaling it, the extra weight of steel only transposes into more strength.
  7. decompiler

    decompiler Member

    It must take one bad-*** bicycle engine to shake loose an aluminum bicycle.
  8. turbo/chaos

    turbo/chaos Guest

    aluminum take in to fact that you cant do the same things you can with a stell frame but who cares it still works great and is faster
  9. sabrewalt

    sabrewalt Guest

    Breaking an Aluminum bike.

    Cheap walmart bikes can break engine or no. My daughter bought one when she moved to Germany and the cobblestone/brick streets plus the constant curb jumping and three straight years of daily commuting + being hit by a Mercades once and eventually the frame failed. Since gas is 8 bucks a gallon. She bought a more expensive bike.
  10. SirJakesus

    SirJakesus Guest

    My XR75 is half aluminum with a steel rear swingarm. I think the dual suspension insulates the aluminum portion of the frame enough to keep it from getting weak. But even so, aluminum frames are usually way oversized with massive welds. I've bombed down trails and dirt roads on the sides of hills and mountains with that thing and it didn't give me any problems. And I was definitely going at or over MB speeds. Have taken some nasty air on it too with no problems. I'm guessing the suspension system will fail somehow before the frame. Like, worn out bushings or the rear monoshock will get trashed and wiggle from side to side or something.
    Keep in mind I hover around 200lbs so im quite a deal lighter than some of the riders here. We'll see how it does with the added weight of the NV hub and staton kit on there this year.
  11. Alaskavan

    Alaskavan Guest

    All my bikes are aluminum.
  12. That right there is saying a whole lot!
  13. BoltsMissing

    BoltsMissing Active Member

    I'm working with steel frames at the moment, but most Alloy frames I have checked out are good and can't wait to build on Allloy.

    Bike shops are in buisness and are not going to endorse motoredbikes, we are on our own. We can survive in the long run with low profit and high turn-over.
    They are in established networks or franchise and work on exploiting demand.
    Which makes it unafordable to many commuters, so we motorbike it !
    What other choice is there ?
  14. decompiler

    decompiler Member

    I have yet to build by first moto bicycle.

    But the next bicycle will most likely be a steel-framed bicycle. A real work horse. One with the modified rear sprocket kit. Solid aluminum mag rims instead of wire spoke rims. Something that can keep taking pot holes and hard bumps in the road.

    My first build is going to be a Kulana Moondog, just like Alan's. And the welds on that bike do look a little bit dodgy. So my next bicycle is going to be a nice old mule. I keep finding those old steel frame bikes at the Goodwill store for $10 to $15 all the time.
  15. RedGreen

    RedGreen Member

    If you have or know somebody that has an aluminum welder, and if you need to put a hole in aluminum you can drill the hole through the frame and then install an aluminum threaded stud in the hole and weld it in place. Doint that way you'll have a good purchase without taking the chance of crushing the frame tube.