Mirror

On a older 2 stroke motorcycles do I need to add 2 stroke oil to the gas when filling up? I don't really know about 2 stroke motors. I just bought a 77 Yamaha RD400. TIA

funcar

Unless someone has modified it, the RD400 has oil injection so you don't need to premix the oil. There is a tank on the side of the bike for 2cycle oil.
I can't remember if it has a window or not to check the level.

Mirror

Sweet thanks!

2kturkey

Yes it has an oil level window - first introduced on the 1972 RD350 and then continuing on through the RD400 upgrade.

I still have an original 1974 RD350A which I have owned for almost 30 years.

scottrnelson

If you just got the bike, you might want to make sure that the oil injection works properly. I had a DT-175 once with misadjusted oil injection that seized a piston because it wasn't getting enough oil through to mix with the gas.

I find it interesting that the 1984 and 1985 RZ-350 had a sensor in the oil tank and turned a light on on the instrument panel when the oil was getting low. You then had to take the seat off to get to the plastic bottle to fill it back up. The worst part was probably that it didn't quite hold a quart of oil, more like 0.8 of a quart. If they had made the tank a tiny bit larger, you could have just dumped a standard sized quart container of oil into it and not have to keep track of a few ounces of leftover oil.

joeyriveira

yes i would suggest you pre mix oil fuel it is a safe measure just bincase the oil feed line fails you'll be covered check for ratio with a local shop oh and use a full synthetic oil better for motor and exhaust mahalo.

kungfushifta

So the newer 2 strokes (Aprilia RS50) you wouldn't have to? Also how reliable is the Aprilia RS50?