Any other 2-stroke lovers??

[cRiPpLe_rOoStEr]

'81 Yamaha RX 80

[cRiPpLe_rOoStEr]

This picture was taken in 2005 at the former Ulbra Museum. From left to right: my dad, me and a Trabant 601

[cRiPpLe_rOoStEr]

Spotted this Yamaha RX 125 yesterday.

[cRiPpLe_rOoStEr]

Brazilian version of the East German MZ

[wheelbender6]

My bicycle with a Chinese 48cc engine kit. Sold it a few years ago.

[Isaac Zachary]

I wonder why there aren't more two strokes.

I'm imagining a two stroke car engine that has a supercharger on it, mainly for scavenging purposes, and could possibly work with overhead valves, so no oil burning necessary (well depending on the type of supercharger possibly).

Sure, it would cost more to build because of the supercharger. But with potentially more than double the power to weight ratio than a N/A 4 cycle, why not?

[cRiPpLe_rOoStEr]

Originally Posted by Isaac Zachary

I wonder why there aren't more two strokes.

When those direct-injection Orbital engines were highlighted by the media and extensively tested by Ford, NOx emissions were pointed out as the reason why they were shelved. Little did everyone know how we would nowadays see LNTs and even particulate filters on gassers

I'm imagining a two stroke car engine that has a supercharger on it, mainly for scavenging purposes, and could possibly work with overhead valves, so no oil burning necessary (well depending on the type of supercharger possibly).

Something like a Detroit, but with spark plugs?

[Isaac Zachary]

Originally Posted by cRiPpLe_rOoStEr

When those direct-injection Orbital engines were highlighted by the media and extensively tested by Ford, NOx emissions were pointed out as the reason why they were shelved. Little did everyone know how we would nowadays see LNTs and even particulate filters on gassers




Something like a Detroit, but with spark plugs?

Ya, i guess NOx would be a problem. Maybe because of higher surface temps, but also because it would be hard to keep fresh air out of the exhaust. Three way catalytic converters work best at reducing NOx in an oxygen starved environment.

[cRiPpLe_rOoStEr]

Originally Posted by Isaac Zachary

Maybe because of higher surface temps, but also because it would be hard to keep fresh air out of the exhaust.

Not sure to which extent fresh air on the exhaust of a 2-stroke with direct injection would be much worse than unburnt mixture on either a carburettor-fed one, or even if either a TBI or port-injection were fitted.

Three way catalytic converters work best at reducing NOx in an oxygen starved environment.

Adding EGR to a 2-stroke engine would be as much of a PITA or even worse as for a Diesel engine.

[cRiPpLe_rOoStEr]

This week I saw a Yamaha RD 135 being used by a motorcycle courier. It did surprise me, as most of them use 4-stroke motorcycles.