I am about to change the oil for my first time in my 1979 Honda CM400 and I just wanted your advice as to what kind (10W-30, 5W-30, etc) of oil to put in and how much.
I was also wondering how often I should change the transmission fluid and clean the carburetor.
Also, a link to where to find out more information like this would be GREATLY appreciated.
Thanks for the time.
jw_loves_trains2010-07-07T19:41:09Z
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Th biggest thing to watch out for is to not put ANY oil that has "Energy Conserving" in the round API sticker on the back of the oil bottle. Putting this oil in will make your clutch slip, due to friction inhibitors. I highly recommend Shell Rotella 15-40 or Rotella Synthetic 5w-40 both work GREAT in motorcycles.
The CM400 features unit construction, so engine and transmission oil are shared. Only clean your carb if poor running results, however, it cannot hurt to remove the float bowl/s every once in awhile and dump them out to remove any sediment.
Your bike has a common sump for the engine and transmission and therefore, the transmission uses motor oil, not conventional automatic transmission fluid. I think it holds something like 2.6 quarts. I use 10W-40 in my '80 and haven't had any problems.
You shouldn't have to clean the carbs as long as everything is running ok. However, they sometimes will run too rich, especially at idle and it's because of the carb floats. Honda went cheap-a$$ed with the carbs and used plastic floats that cannot be adjusted for level. When they warp out of shape and fail to hold the correct level, you pony up $60 each for them. And the carb gasket kits are really expensive, so as long as it runs ok, don't mess with the carbs. Otherwise a neat little bike. Not nearly as fast as the standard tranmission model, but easy to learn on and fun to ride.
There's a Yahoo owners group website that deals with the CM400A. You might check that out. I personally haven't found it loaded with really sharp, experienced people like the Kawasaki Voyager site, but you should still be able to glean some good info from people.
I'd use Chevron Delo 15w40 or Shell Rotella T 15w40 These are designed for use in diesel crankcases. While I'm a fan of synthetic oil it's not recommended for older engines.
And just in case you're confused between bikinkawboy and jw_loves_trains, BK is right; your bike doesn't have a clutch. The "A" stands for "automatic", so jw's advice is irrelevant.