I am a frame builder that mainly builds steel fillet-brazed cyclocross frames but recently I have become interested in building a BMX frame. I know nothing about BMX. With the type of frames I build most people are worried about weight but I believe it is a bit different in BMX because of the strength issue. My question is this. What thickness tubing is adequate for BMX frames and are there fillet-brazed BMX frames out there, would they even hold up under the load? I ride my 'cross bike off of curbs but thats not exactly BMX. I would also like to know what makes a good BMX frame and where is most of the impact absorbed. I would appreciate any info. My bike frames are under the name MEECH Custom Bikes and can be viewed on Photobucket @ http://photobucket.com/meech151 as well as http://meechcustombikes.blogspot.com/
I'm not sure how thick the tubing is, but it's normally made out of 4130 chromoly, and I've never seen any fillet-brazed frames. I'm pretty sure the brunt of the force is normally at the BB/CS/DT junction, but most frames I've seen crack or snap always do it at the HT/TT/DT junction.
Thanks for the info. Are most BMX frames tig-welded steel, or aluminum? Do they put any type of additional support around the HT area? Do you think a fillet-brazed frame would hold up? I appreciate the help. Later.
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My frame has a HT gusset that is welded on after the down tube was welded to the HT.
This is the area that fails the most with BMX frames.I sure broke my share of them.
I can take a picture of that area and post a picture of it .
Any good BMX frames are tig-welded steel. A lot of companies put a gusset on the toptube and/or the downtube for added strength. I'm not sure how fillet-brazing is done, so I can't really determine if it would be strong enough.
Do most BMX frame builders offer any kind of warranty or is it just a given that it is gonna get broken eventually. Is steel or aluminum better for BMX? I build with steel, I despise aluminum, however I don't know what makes a good BMX frame. I would think aluminum is gonna break a lot. What size headsets do you all use, and what type of BB?
Most companies offer a warranty. It ranges from a year to lifetime. Steel(4130 Chromoly) is better to make street/dirt/park frames, but most race frames are made of aluminum. 1 1/8" headset. And most freestyle frames use Mid BB's, whereas race frames usually use European BB's.