2T oil injector pump

[Homer88]

Having one of this on my WR200, I notice that my premix ratio
isn't quite accurate as I'll like it to be.

Eg. I'll top up 1 liter of Castrol TTS into the 2T box.

And if I keep track of my fuel top-ups, at the end of 1 week, even though I have used up 40L of petrol, my 2T box still has 500ml left.
Using this ratio, I'll get a premix ratio of 1:80?!?!?

Isn't this a bit too little 2T oil for a 92 WR200?

 

[TONY78]

80:1 Certainly doesn't sound correct, especially for a wr 200. I would double check your calculations, but if you are correct i would consider removing the oil injection system a running premix in the bike at about 30:1. I have a dt 200, which has a similar type set up. Removing the oil injection is the best thing i have ever done. It means there is one less thing that can go wrong, and it means the bike is always getting the right oil/fuel mixture.

 

[Homer88]

Thanks for the suggestion.

Are there any parts readily available your for DT200 over in Australia?
Eg. Colored front shrouds, plastic tank aka YZ style etc?

Here in Singapore, the front shrouds only comes in the stock white color.
And to "hot-rod" it, parts are not readily available.

 

[TONY78]

No plastics suit other then those specified for a dt, However "go fast bits" are fairly common, for both a WR or a DT. Pro circuit and fmf make pipes to suit both models and make a remarkable difference in otherwise restricted bikes.

 

[David Trustrum]

Oil injection has the advantage that when you run out of gas in the middle of nowhere you can blag some straight petrol from the local farmer.

Many people slag off oil injection which works just fine in zillions of road bikes everywhere.

These old world, Closed Minded people cannot accept the risk that the oil pump mechanism will continue to meter oil reliably into your precious engine. Oil injection is smart in that it will back the level off at low rpm when the requirement is much less than at high rpm & throttle positions.

When I discovered (just in time) that my oil level of my old DT200 was not going down I became one of these people.

We meet on Tuesday nights.



When you convert, (zombie voice: “join us, don’t be afraid”) block off the line to the carb & saw off the oil part of the reservoir so you can store your emergency oil bottle there.

 

[TONY78]

Oil injection may work fine for road bikes, but the treatment a dirt bike gets is a far cry from a soft road cruise. I guess i am just one of those new age old timers who think simple is best, but if your still worried about your fuel mixture, either get the injection system inspected or better yet bin it.

I'm not sure about the WR but i know my DT had the oil stored in the frame, quite bizarre i know!

 

[David Trustrum]

Yeah that’s what I’m advocating, bin it!

On the other hand have you ever seen an RGV going for a “soft road cruise”?
That’s the reason there’s not many left in one piece!

In the frame huh? Just like me old TT500. (What a pig that was). Still good idea to use one part for two or more jobs.

 

[Homer88]

How do you convert it to a pre-mix bike?

Do you just plug in the hole at the carb that allows 2T into it, remove the 2T oil box from the rear.

I would like to remove the pump mechanism thouroughly from the bike though.
Could anyone kindly list out a step-by-step on how to do this mod?

 

[TONY78]

I'm not exactly sure on the WR, but the conversion on my DT was pretty simple (they should be relatively similar).

Locate the injection unit and follow the oil line to where it meets the fuel system/manifold. Disconnect the oil line and plug the existing opening.
The injection system on my DT was operated by a throttle cable, this should be the same for the WR. If so, disconnect the cable form the unit (may require side cutters) and simply tuck the excess cable under the seat.
Unscrew the bolts holding the injection unit to the motor and simply remove the injection kit from the bike. Using the contact surface of the injection unit trace the shape on to an aluminium plate and cut out the shape to size. Use this plate to cover the opening left by the injection unit (you may need to also cut out a gasket to suit the opening aswell).

All in all it is a pretty straight forward operation with only a few headaches and swear words necessary (big hands, small bike). Good luck

 

[Vic]

If your bike has an additional oil line that feeds the crank bearings and you block it off without taking the appropriate measures, you will fry said bearings. :eek:

 

[David Trustrum]

Good advise -if it was an early 70s suzuki.

No he’s right -it’s always worth a check, but it will only have one line & it will feed to the carb on a Yamaha.

 

[Homer88]

Thanks for all the details.
I'll work on my bike tonight and see how it does.

On this topic, what are the jetting settings on your bike?
On my DT200WR, Procircuit system, Boyesen Power Reeds, airbox snorkel removed and sidecover drilled, and area underneath the CDI cut out.
And the jettings on the Mikuni TM30SS is 230 main, 27.5 pilot.

Should I change the carb to a bigger one? But I dunno what jets to use though...

 

[spanky250]

Oil injection does not use as much oil as pre-mix because the oil is delivered directly to the bearings, instead of just having a mist floating through the engine and hoping some of it lands where it needs to be. Dave is correct with his statement that the injector pump is rpm-sensitive, it will throttle the oil down at low rpms. This is the main reason the oil consumption is lower.

As for removing the pump, I'm not sure about the construction of that engine, but some injection-designed engines can not be run reliably without the injection system, because the ignition-side crank bearing will not be properly oiled by pre-mix.

If you really feel that the engine is not receiving enough oil, the pump is adjustable.

 

[David Trustrum]

Except that on Yams, - unless they have changed them for this model, the only tube off the pump leads to the carb where it is dispensed into the airstream as if it was mixed with the gas initially.

My main concern is that the pump keeps working & the lines don’t get clogged up, which with the dirt about the oil reservoir is a possible issue. If used only on the road I'd keep the pump.. . . Maybe.

 

[Homer88]

I can agree that the only line leading out from the pump is to the carb.

And I do notice that some dirt do get into the oil reservoir and I took it out to clean everything. Maybe I'll keep that tank after I remove the 2T pump instead of having to bring a 2T bottle along with me all the time.

What would be a good premix ratio using Castrol TTS?