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Old 03-08-2012, 07:59 AM   #14
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Joined: Nov 2010
Location: Desert Beach SoCal
Oddometer: 156
Originally Posted by malokam View Post

Okay, if I have to choose between the two, I would deal with dual shocks than dealing with mixing oil.
Is there an after market 2T oil injection kit available for any of the smokers?

When the US imposed the 125cc limit (and later 50cc limit) on emissions legal 2-strokes the manufacturers dropped oil injection on larger engines (except for the bikes mentioned, the KDX200 and the DT200, for non-US sales & distribution). There is not enough sales volume to modify the larger competition engines with oil injection for a market that is Administrated out of existence by the EPA.

I have not seen an aftermarket gear driven oil injection pump system for sale in over two decades.

The snowmobile and watercraft outboard engine industries moved to crankcase pressure driven oil injection pumps with reliable success after a few initial problems (before the EPA further regulated 2-stroke watercraft outboards based on oil spillage concerns). Metering the oil feed rate based on engine rpm and engine load (crankcase pressure) proved to be very reliable to the point that with synthetic oil 50+:1 fuel/oil ratios became commonplace on outboard engines. This method of oil metering also addressed much of the WOT throttle chop problems typical of 70's and 80's pre-mix 2-strokes because the metering was not based on throttle position and fuel delivery (and also less throttle position sensitive than mechanical lube pumps). Crankcase pressure during engine braking builds and these pumps by system design meter oil similar to WOT pressures to resolve this problem. This was a big design concern in watercraft engines because a prop in water is always loading the engine at peak torque for the throttle position until the throttle is chopped (load conditions similar to sustained WOT desert conditions until you hit the fishing area), None of the manufacturers applied these pumps to a production motorcycle engine (no profitable volume market due to regulations).

You might do a web search as there are people who have successfully applied a marine outboard 2-stroke oil pump to their motorcycle. IIRC porting and packaging the pump were the major problems, along with oil tank position & priming concerns.

If you don't want to go to that effort, the legal 70's era bikes or a 200cc import from Canada are the oil injection options.
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