Steel vs Aluminum


New Member
Local time
10:17 PM
Apr 2, 2008
Ft Wayne Indiana
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.
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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
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.
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.
It must take one bad-*** bicycle engine to shake loose an aluminum bicycle.
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
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.
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.