2 stroker question.

**219R6** · 03-14-2010, 07:25 PM

I found an old rg 250 gamma to use to race vintage but I don't know much about 2 strokers...
Is it normal for some oil to come out the tail pipe when it is running?
Will that go away when it warms up maybe?

Thanks

**Brian P** · 03-14-2010, 07:37 PM

All two-strokes will let out oily smoke. Oil is mixed with the fuel - that's how they're lubricated. Nature of the beast.

If you use the right engine oil, it will smoke somewhat less.

**john bickle** · 03-14-2010, 07:39 PM

Originally Posted by 219R6

I found an old rg 250 gamma to use to race vintage but I don't know much about 2 strokers...
Is it normal for some oil to come out the tail pipe when it is running?
Will that go away when it warms up maybe?

Thanks

It's oil injected so it's probably running extremely rich. Most two stroke street bikes started out a minimum of about 50 jets sizes too rich. Plus the injector pump is dumping more oil then necessary.
It would be worth the money to run up to Peterborough and talk to Andrew Jones at Adjustment Tech. Do a few Dyno runs and get it closer to the ball park. Andrew has a lot of experience with Gamma's.
The only other person ,other then Andrew that I would let touch a two stroke on a Dyno is Sandy at Pro 6.
To answer your question ,probably won't go away. It might dry up a bit with harder track use,, but only because you're getting the pipe hotter.

**invictus43** · 03-14-2010, 07:42 PM

And just to expand on what Brian said, the oil is part of the mixture..and it's not always completely burned..and it comes out of the mixture in the exhaust and ends up condensing at the end of the exhaust at times. I wouldn't worry unless you have WAY too much oil in the mixture, then you'd lose power and possibly foul the plugs.

**RC8BOY** · 03-14-2010, 07:46 PM

Having owned many two strokes years ago, this brings back alot of memmories! You can disconnect the oil injection system and pre-mix the oil/fuel mixture instead. I still remember the manuals from back then warning people to make sure the mixture was at 20/1. I would run my bikes at 50/1 without any problems. I'm sure with todays oils, you can probably go even leaner. When street riding it can be a pain in the butt having to bring pre-measured oil with you but as a track bike, I would treat it like my dirt bike. Fill up a jerry can of pre mix and your off to the races.

**invictus43** · 03-14-2010, 07:54 PM

Originally Posted by RC8BOY

Having owned many two strokes years ago, this brings back alot of memmories! You can disconnect the oil injection system and pre-mix the oil/fuel mixture instead. I still remember the manuals from back then warning people to make sure the mixture was at 20/1. I would run my bikes at 50/1 without any problems. I'm sure with todays oils, you can probably go even leaner. When street riding it can be a pain in the butt having to bring pre-measured oil with you but as a track bike, I would treat it like my dirt bike. Fill up a jerry can of pre mix and your off to the races.

For street riding, I left mine alone. It's the street after all..cold..warm..humid..dry..you never know. When you start getting to extremes the jetting and mix get trickier..worst thing would be to squeak it.

For the track you can jet and mix it for the weather and be more careful. Love the 2-strokes..

**zacm7** · 03-14-2010, 08:26 PM

2 strokes are amazing little bikes i am actually trying to find a rz350 just to get to and from work. you will have fun with it they are amazing little machines, with sweet powerbands

**john bickle** · 03-14-2010, 08:58 PM

Originally Posted by RC8BOY

I still remember the manuals from back then warning people to make sure the mixture was at 20/1. I would run my bikes at 50/1 without any problems. I'm sure with todays oils, you can probably go even leaner. When street riding it can be a pain in the butt having to bring pre-measured oil with you but as a track bike, I would treat it like my dirt bike. Fill up a jerry can of pre mix and your off to the races.

Having done 84 dyno runs on my last 125 GP bike we found there was no advantage to mixing the oil leaner then 40:1 . But the big key is running good oil and good gas.Cheap oil will burn poorly and foul plugs.Poor fuel will accent that. A747 was the main oil then Silkolene Pro 2 which was designed from A747. If you disconnect the oil pump you should pull the gear.
Pre mixing big volumes of todays oils isn't allways good as they do seperate and some very quickely,, again pending what you use.

**RC8BOY** · 03-14-2010, 10:17 PM

Originally Posted by john bickle

Having done 84 dyno runs on my last 125 GP bike we found there was no advantage to mixing the oil leaner then 40:1 . But the big key is running good oil and good gas.Cheap oil will burn poorly and foul plugs.Poor fuel will accent that. A747 was the main oil then Silkolene Pro 2 which was designed from A747. If you disconnect the oil pump you should pull the gear.
Pre mixing big volumes of todays oils isn't allways good as they do seperate and some very quickely,, again pending what you use.

For me in those days it was more about the cloud of smoke I was leaving behind while riding downtown. I wasn't to concerned about gaining an extra pony or two. Thanks for the info though.

**Meleemark** · 03-15-2010, 01:47 PM

I miss my old RZ350.....I don't miss smelling like an oil rig.

**forexman** · 03-15-2010, 02:13 PM

Yeah I miss my 2 stroke motor too.. Oil from the tailpipe is normal, too much means your running way too much oil, but its better than having a seized motor.