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YFZ450Ridr
06-19-2006, 07:59 PM
ive noticed that alot of bikes are a single over head cam and some are a double over head cam. my bike is a dohc, as well as a yfz and some others. the 450r is a sohc. is there a difference in the two? any major benefits? ive wondered about this for a long time. i can see where a sohc would be better because its less moving parts in the motor and is cheaper and easier to buy a new cam. can any one explain the pros and cons of each?
400exstud
06-20-2006, 08:14 AM
One advantage of a DOHC is that you do not need to check your valve lash as often.
rooster300ex
06-20-2006, 08:30 AM
dohc makes more power
Caseys 300ex
06-20-2006, 10:38 AM
If a dohc gives more power than how come a 450r has more than a yfz 450? Cuz dirt wheels says the 450r has more power than the other 450s.
ohsobad_chevy
06-20-2006, 10:57 AM
Originally posted by Caseys 300ex
If a dohc gives more power than how come a 450r has more than a yfz 450? Cuz dirt wheels says the 450r has more power than the other 450s.

I read the exact same thing. I never did pay attention that the yfz's are dohc, but now that someone mentions it, thats cool to know.
rooster300ex
06-20-2006, 10:58 AM
I thought in stock form the yfz has more power then the 450R
400exstud
06-20-2006, 11:13 AM
Cam setup isn't the only determining factor in an engines power.
rooster300ex
06-20-2006, 12:19 PM
Originally posted by 400exstud
Cam setup isn't the only determining factor in an engines power.


True
LT250RMan
06-20-2006, 12:26 PM
on a engine with a DOHC one cam runs the intake valves and the other cam runs the exaust valves, a engine with a DOHC will rev faster than a engine with a SOHC.
HAVOK
06-20-2006, 03:30 PM
http://www.honda.ca/MotorcycleEng/Technical/FlashTech.htm
boricua
06-20-2006, 08:41 PM
it also makes it easier to have multiple valves per cylinder per cam.... you can adjust the timing of the intake AND exhaust valves
seperatly too. i would say the draw back is that it cost more for upgrades, more moving parts that can go bad.....
but usually the pros out weigh the cons.....
krt400ex
06-22-2006, 07:10 AM
Originally posted by rooster300ex
I thought in stock form the yfz has more power then the 450R


yes, but only the bikes before '06
TheBlasterMan
06-22-2006, 12:45 PM
figured this desereved to be posted........

http://paultan.org/archives/2005/06/22/sohc-vs-dohc-valvetrains/