Custom Fighters - Custom Streetfighter Motorcycle Forum banner
1 - 8 of 8 Posts

·
Registered
Joined
·
334 Posts
Discussion Starter · #1 ·
looking to make a new steering stem for my buell. The factory is steel and plan on staying steel, just not sure what grade steel to go with. Right now I am leaning towards a 4140 chrome-moly.

As is the material specs are :Yield Strength: 60,000 psi
:Hardness: Hard (Rockwell C25)
:Can be hardened up to Rockwell C60

anyone have any input on this? If 4140 is a good material to use, would it be fine as is or should it be heat treated?

also, the factory stem is center drilled all the way through, not solid, was going to do the same.

any help, tips, links would be great.

thanks
 

·
Is my bike ok?
Joined
·
15,255 Posts
Definitely doesn't need to be heat treated if you just think about it. Like Yantosh said, there's bearings in that that take the frictional loads, so surface hardness really isn't a concern.

Id be more worried about it being malleable than hard. Brittle things make for sucky suspension components. Ease of machining is another area to consider when looking at hard metals.

Anyway, like Yantosh said, AL gets the job done. There's no stem you can swap/mod in to place? Making one from scratch would be fun though. BTW, whatcha working on? Ya gotta thread going?
 

·
Registered
Joined
·
334 Posts
Discussion Starter · #4 ·
ya, i figured i want something thats pretty strong but not brittle.

Im going to be machining a new set of custom triples for my bike and a stem. I could buy a used stem but whats the fun in that??
 

·
Registered
Joined
·
23 Posts
4140 will be tough to machine. I was making a piece of 4130 on the lathe yesterday, and the carbide didn't have any issues, but I burned a drill bit right up in it, and I'm not sure if the center drill faired very well either.
I guess if you are just using carbide tools, it would be ok. The advantage to 4140 vs mild steel is the strength to weight. So if you are using a solid chunk of it, the same dimensions as mild, then you aren't taking advantage of the 4140. And since you don't really need the strength, just go with mild steel. Or even aluminum as the other guys mentioned.
 
1 - 8 of 8 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top