Ride_or_Die_kid
09-20-04, 06:40 PM
hey some of these kids at school want to know so could you guys plz tell me if they are or not?
BMX - ok i know this may sound stupid but are chromo and chromoly the same thing?
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PGZX3
09-20-04, 08:50 PM
yes, but don't confuse chrome with the two
BMXTRIX
09-20-04, 09:19 PM
chromo and chromoly definitely mean the same thing. Typically a good steel frame is made of 4130 chromoly where the numbers 4130 actually mean the amount of chromium and molybdenum that are added to the steel to make it better. I am not 100% sure what the numbers specifically are, but I believe that 41 is .41% chromium and .30% molybdenum. Plus carbon and iron to make up the steel.
Chromium is in fact the same stuff that is put on bikes as a top layer that makes them all silvery looking. But, that is a much higher concentration of chromium which makes it silver. A chromoly frame (4130) actually looks kind of gray, not silver, because there is not enough chromium in the tubes to actually produce that silvery effect.
Do NOT confuse chromoly with trimoly though. Trimoly is typically a frame where one or two tubes are made of chromoly and the rest are made with mild steel (high-tensile steel).
Chromium is in fact the same stuff that is put on bikes as a top layer that makes them all silvery looking. But, that is a much higher concentration of chromium which makes it silver. A chromoly frame (4130) actually looks kind of gray, not silver, because there is not enough chromium in the tubes to actually produce that silvery effect.
Do NOT confuse chromoly with trimoly though. Trimoly is typically a frame where one or two tubes are made of chromoly and the rest are made with mild steel (high-tensile steel).
Ride_or_Die_kid
09-21-04, 05:34 PM
thank you for your help.
jrt1990
09-21-04, 06:15 PM
ya they think that because on all our bikes at school the sticker on the seat tube will either say cr-mo and chromoly and they think its different, and trimoly is the same as chromoly top, seat, and downtube.