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2-stroke wish list

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Sorry Chokey, I thought I remembered you as an expat Warshingtonian.

 

 

No, afraid not. I've been all over the Eastern U.S., but never West of the Mississippi.

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Why?

 

I prefer mine to be crisp and sharp. More responsive that way.

 

I started out doing that because I want my parts to last as long as possible,  now I just like it that way.   I ride half sandy single track and half clay, trials tire too I'm not a wheelspin rider

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Your dealer may be a great rider, but he doesn't know what he's talking about in regards to fuel injection. EFI and DI are the exact same thing. The only difference is where the fuel is injected. EFI injects it into the intake tract, and DI injects it into the combustion chamber.

No open-loop Fuel Injection systemss can infinitely adjust like a closed-loop system with a lambda sensor can, but the 3D programming maps generally have enough flexibility to deal with mild engine modifications and can handle moderate elevation changes.

Keep in mind I asked him about this 8 years ago, when two stroke EFI was tested but failed. at the time the systems made the bikes pigs. But EFI now has matured as a technology and could only make the smokers better.

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I'm with MrBlahh to some extent. Lean, snappy power doesn't make the best traction and it's more tiring. I'd never jet fat enough to load up the motor or foul plugs but I like my two stroke bikes toward the rich end of the spectrum at least at the lower rev range.

My 300 runs so smoothly when the jetting is spot on.. when it's crisp and sharp. "Pilot riding," extremely technical FiveMilesOfHell stuff is way easier and the rear end more tractable when it's jetted this way.

Personally I don't understand why some guys run jetting rich just to run it rich. Decades ago it may have been an anti-seize measure, but it's not at all necessary today.

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Hate to say it but the fourstrokes may see DI before the twostrokes. Hyundai and mazda for example are all ready using it on cars. The biggest difference between efi and di  in application is the pressures involved. EFI your basically injecting into a vacuum, doesn't take much pressure. DI your injecting into a high pressure combustion chamber at the very last second before TDC, you need to over come that pressure or the fuel isn't going in.

Edited by highmarker

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Hate to say it but the fourstrokes may see DI before the twostrokes. Hyundai and mazda for example are all ready using it on cars. The biggest difference between efi and di  in application is the pressures involved. EFI your basically injecting into a vacuum, doesn't take much pressure. DI your injecting into a high pressure combustion chamber at the very last second before TDC, you need to over come that pressure or the fuel isn't going in.

 

GM uses it too.

 

Pretty Honda and some Euros use it also.

 

The car I've has since 2010 (A Holden) is DI.

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The oil injection systems i have seen just pump oil into the intake tract.

I wonder if anyone has tried pumping oil directly through the end of the crank to the rod bearing where it will be flung all over the piston, bore, and small end bearing.

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The oil injection systems i have seen just pump oil into the intake tract.

I wonder if anyone has tried pumping oil directly through the end of the crank to the rod bearing where it will be flung all over the piston, bore, and small end bearing.

My suzuki has it feed the crank via passages through the case, and lubes each of the cylinders directly in two places.

 

This isn't my bike but its the same you can see oil lines here:

image_zps942817e3.jpg 

The ones that do the crank are harder to see, they run under the engine:

 

RVG250_21_zps5466876c.jpg

 

Sorry about bringing up this bike yet again.

Oh, and people have tried fuel injecting these too BTW.

Edited by BushPig

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My suzuki has it feed the crank via passages through the case, and lubes each of the cylinders directly in two places.

 

This isn't my bike but its the same you can see oil lines here:

image_zps942817e3.jpg 

The ones that do the crank are harder to see, they run under the engine:

 

RVG250_21_zps5466876c.jpg

 

Sorry about bringing up this bike yet again.

Oh, and people have tried fuel injecting these too BTW.

 

what is that thing?

i want one.

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Hey, this is the place to ride. I am about five miles from th e trails. The trails offer any type of challenge you would want. Let me know when you want to come down and ride. May be able to help out with info if you need..

my little DS80 has a similar pump system, Crank and intake injection.

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my little DS80 has a similar pump system, Crank and intake injection.

 

I take it you're using a smart phone to post, and meant to quote some from this decade?

 

TT has some special moments sometimes. They are mostly on top of it.

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I take it you're using a smart phone to post, and meant to quote some from this decade?

TT has some special moments sometimes. They are mostly on top of it.

na it was for sure the post i wanted to quote lol
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My suzuki has it feed the crank via passages through the case, and lubes each of the cylinders directly in two places.

 

This isn't my bike but its the same you can see oil lines here:

image_zps942817e3.jpg 

The ones that do the crank are harder to see, they run under the engine:

 

RVG250_21_zps5466876c.jpg

 

Sorry about bringing up this bike yet again.

Oh, and people have tried fuel injecting these too BTW.

 

 

the ones that supply the crank,

is the crank drilled to allow oil to the rod bearing?

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the ones that supply the crank,

is the crank drilled to allow oil to the rod bearing?

 

I may have gotten myself in hot water here, as I think my previous post was not entirely 100% accurate. Although I put the thing back together 5 months ago, it seems the oil was injected on the sides of the main bearings and must work its way to the big end.

 

Edit: no I didn't write it injected through the crank onto the big end. Phew!

Edited by BushPig

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Direct injection 2 strokes is the BIG answer.  This would make 2 strokes more powerful and cleaner burning with less emissions to make tree huggers happy.  I street ride and road race 4 stroke street bikes, but when it comes to dirt bikes why even bother with 4 strokes when everyone knows 2 strokes are superior due to their power/weight ratio and simplicity.

Edited by sonicnofadz
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the rotax DI twostrokes outer crank bearings are sealed in a cavity filled with Kluber Isoflex grease so there is no need to slobber a bunch of (excess) injector oil in the crankcase to drip feed them. Inner bearings are in a oil bath that also lubes the water pump drive shaft. The oil that is injected into the case is aimed right at the big end rod, not sure if it matters but that where they put them. Small end rod bearing is cageless, which means it can use a few more needles than a caged bearing in increasing durability. They were doing that before DI though.  Because the fuel isn't going through the crankcase the oil isn't diluted so has more of a chance to drool around and stay on stuff before it finds it way into the combustion chamber.  Computer controlled electric oil pump which will actually turn the oil off at idle and control on throttle and off throttle oiling. They use a scary little amount of oil.

Edited by highmarker
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