BannedCR500Riders.com

Ok so anyone here have experience with oil injection carbs like snow mobiles and jet ski apps?? I was thinking how much nicer it would be to have a similar setup on the 500.

Heres a list of why...
1. Dont have to worry about not using up all your premix and having to toss old stuff.
2. A variable ratio system would allow you to TUNE the amount of oil depending on load/TP/rpm.
3. You could esily run a quart or more of on board oil capacity, probably enough to last a whole weekend of riding without having to mix.
4. The system has proven to be very reliable, so just a matter of swapping the stuff over and a little fabbin...
5. Would really make things easy for a street legal setup!! (I think all the street legal guys would appreciate not having to mix "at the pump"...)

The setups on some old enduro bikes were dead reliable, I dont know why they dropped it so early on.

Oil injection has a few issues for real dirt bikes... as the system is 100% rpm controled...

This means......


1. When engine braking downhill ( Closed throttle, high revs) lots of oil is going into the motor un-nessasarly). Could foul a plug.

2. When lugging a motor uphill (Lots of load, no revs) There is too little oil going into the motor.


Otherwise its a good system.


My boys PW50 is equippped that way...

Gas and Go!

I've seen way too many oil injection problems, most people who have a bike/quad, etc with oil injection eliminate it after going through a few topends and rod bearings and not knowing why.

Bob, they are not 100% rpm controlled, there is an extra throttle cable that hooks up to the oil pump that will make it flow more at wfo and less when the throttle is closed . It a good idea, but for some reason I see oil injection motors blow up all the time. Maybe the pumps get gummed up, or maybe from long periods of sitting it takes a while of running for any oil to come out ( fill the lines) who knows. Ive seen them work great in watercraft, but not so in the offroad vehicles and maybe thats because of the more constant load and rpm.

believe me, I would love to have oil injection, I just don't trust it. Hell, I have to dispose of 5 gallons of 100 octane mixed 44:1 with 927 because its been sitting since april, if we had oil injection, that would save me some coin.

dannygraves wrote:believe me, I would love to have oil injection, I just don't trust it. Hell, I have to dispose of 5 gallons of 100 octane mixed 44:1 with 927 because its been sitting since april, if we had oil injection, that would save me some coin.

Anytime you are going to do that again call me, I'll dispose of it for ya

I had a 2 stroke 125 Yamaha with a oil injection system, and it didn't work well. I ended up seizing the top end on that bike and only later realized the oil level in the reservoir wasn't going down very fast. Premixing is no big deal, and you can control the ratio to your liking.

The biggest draw back is with premix if your bike is running you are getting oil, with injection your oil tank can run dry but motor just keeps on going, well for a few more minutes anyway.

ou812 wrote:The biggest draw back is with premix if your bike is running you are getting oil, with injection your oil tank can run dry but motor just keeps on going, well for a few more minutes anyway.

The oil tank on our boat had a buzzer and shutoff built in.

My jet ski is on the origional top end from 1994, since it is at full throttle nearly 100% of the time I think that proves the robustness of the system. It is also a "variable ratio" system. It has a small magnetic float that turns on a warning light if you get low on oil. One gallon of oil lasts me several gas tanks (you should be checking your oil whenever you fill up anyways).

FYI, its a paralell twin, 2 stroke 650cc, since its a 3 seater I regularly tow skiers/tubes so the loads on the boat vary quite signifigantly...

ou812 wrote:with injection your oil tank can run dry but motor just keeps on going, well for a few more minutes anyway.

If you let your oil run out...your just stupid.
The injection on our snowmobiles has worked great. The programming on our Ski-Doo's are actually quite 3 dimensional. At low rpm, at an idle, or coasting from speed there is no oil injected. Under load, the oil ratio is gradually reduced as rpms increase. So it basically runs the richest when you whack open the throttle from a stand still. Runs leaner at high rpm, and runs free of oil when you cut the throttle.

I should note this isn't for all snowmobiles, just Bombardier. They've succeded in building fantastic two stroke motors that emit fewer harmfull emitions than fourstrokes, and make more power from bottom to top then even a larger two stroke motor from Polaris or Arctic Cat. Yamaha no longer manufactures 2 stroke smowmoblies.

I think this idea would be great for SMotards. Where would it go? Tucked inside the left side panel?

Looking at my Sea Doo the biggest part of the system is the tank, im thinking just using about a quart size overflow style container. The hard part would be getting the right size single carb. The pump is mearly a diaphram on the carb...

If you let your oil run out...your just stupid.

Ever see how some people set there chain?

The oil tank on our boat had a buzzer and shutoff built in.

True but you now rely on a system that can fail. A MX bike was , pre 4 stoke stuff, was designed to be simple.

Looking at my Sea Doo the biggest part of the system is the tank, im thinking just using about a quart size overflow style container. The hard part would be getting the right size single carb. The pump is mearly a diaphram on the carb...

If you really were going to do that, you may want to go to a floatless carb and run every thing off vacum.

http://www.swedetechracingengines.com/p ... retor.html

Thats one possible way.

dannygraves wrote:
Bob, they are not 100% rpm controlled, there is an extra throttle cable that hooks up to the oil pump that will make it flow more at wfo and less when the throttle is closed .

Sweet!

The last time I fiddled with oil injection, you were making a "boo-boo" in your Huggies.....

AlisoBob wrote:

dannygraves wrote:
Bob, they are not 100% rpm controlled, there is an extra throttle cable that hooks up to the oil pump that will make it flow more at wfo and less when the throttle is closed .

Sweet!

The last time I fiddled with oil injection, you were making a "boo-boo" in your Huggies.....

Yup, I was probably swimming towards the egg

M.F.D.B. wrote:Looking at my Sea Doo the biggest part of the system is the tank, im thinking just using about a quart size overflow style container. The hard part would be getting the right size single carb. The pump is mearly a diaphram on the carb...

the carb wouldn't be an issue, just re-jet it richer, most oil injection on bikes and quads either have an extra nipple on the carb boot, or a banjo fitting on the crank case or cylinder. run the same carb, just leaner.
then you have to mod the clutch cover and have a gear and shaft coming out to drive the pump, then a double throttle cable (like the banshees have) to drive the throttle adjustment side.
Like I said before, I think its a great idea, I just don't trust it, I've seen too many blown up blasters and old yamaha at-1 and ct-1's to really trust it.

dannygraves wrote: Yup, I was probably swimming towards the egg

I aint that old...

AlisoBob wrote:

dannygraves wrote: Yup, I was probably swimming towards the egg

I aint that old...

ok...I won't ask how old you really are...

Danny, on the Sea Doo carbs the pump is a vacuum diaphram on the carb body. Its not mechanical...So that might simplify things!!

Also, its a thumb throttle like a modern quad, on one throttle cable...

dannygraves wrote:

AlisoBob wrote:

dannygraves wrote: Yup, I was probably swimming towards the egg

I aint that old...

ok...I won't ask how old you really are...

He does look a lot like Moses?? HAHAHAHA

M.F.D.B. wrote:Danny, on the Sea Doo carbs the pump is a vacuum diaphram on the carb body. Its not mechanical...So that might simplify things!!

Also, its a thumb throttle like a modern quad, on one throttle cable...

hm, I wonder how that works...is it a vacuum/gravity feed?

britincali wrote:

dannygraves wrote:believe me, I would love to have oil injection, I just don't trust it. Hell, I have to dispose of 5 gallons of 100 octane mixed 44:1 with 927 because its been sitting since april, if we had oil injection, that would save me some coin.

Anytime you are going to do that again call me, I'll dispose of it for ya

Ill be 2nd in line

My grandsons bike is a PW50

dannygraves wrote:

M.F.D.B. wrote:Danny, on the Sea Doo carbs the pump is a vacuum diaphram on the carb body. Its not mechanical...So that might simplify things!!

Also, its a thumb throttle like a modern quad, on one throttle cable...

hm, I wonder how that works...is it a vacuum/gravity feed?

As far as I know gravity brings the oil to the diaphram and vacumm pulses get amplified and act as the pump...If you think about it, there isnt really a whole lot of oil be moved...