Full Restore of a TY 350

[Gordo83]

Not to change the subject, but what is the white jug with the black pipe going to ? doing there. I've had an 85 TY350 for several years and haven't seen this add-on. This is in regards to the craigslist TY350
in Kansas City.

[Sting32]

Originally Posted by Gordo83

Not to change the subject, but what is the white jug with the black pipe going to ? doing there. I've had an 85 TY350 for several years and haven't seen this add-on. This is in regards to the craigslist TY350
in Kansas City.

I've seen the mod, on several of these old Yamaha bikes in Wichita area, back in the days. I ended up with a 350 not long ago that had this, but I dont really know what it does... Because, I only rode Bultaco's back in those day, so cant tell you exactly, but I think it was Some theory about response time on throttle using this "can" which I believe stores up "vacuum" so that when you crack the throttle it acted differently. I could be wrong...

[brewtus]

Originally Posted by 2whlrcr

That's a big plus, because half of the people in the US can't. And I'm including the ones that were born here too.

Tell me about it.

[PSchrauber]

Originally Posted by Gordo83

Not to change the subject, but what is the white jug with the black pipe going to ? doing there. I've had an 85 TY350 for several years and haven't seen this add-on. This is in regards to the craigslist TY350
in Kansas City.

That is a hand made Yamaha YEIS System, that they had back then.

YEIS stands for: Yamaha Energy Induction System

The YEIS consits of a plastic container, which is connected with a rubber hose to the inlet of the engine.
This creates a kind of reservoir between the carburetor and cylinder, in which the two-stroke mixture will retained when the slide (little or no gas) or the gates/reeds of the cylinder are closed until the slide or gates/reeds by the piston are opened again.

The system also works as a vibration damper in terms of sound (Greetings to Hemholz) at certain speeds between the combustion chamber and carburetor as the gases oscillating back and forth.

The YEIS causes a better engine response, more torque at low and medium revs and a lower consumption by up to 10%.

[xtnomad]

If you are still looking, I boxed away quite a few parts years ago, Rings,Pistons Gaskets Reeds ect. I have a stock cylinder and head still on the shelf. PM me.

[RobbieO]

We used to call that thing a "boost bottle". I had one on my Italjet and the improvement of low end response was noticable!!!