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premix in oil injected bike. Disconnect oil pump?

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bike is a 2000 yamaha rt100. There is a small hose from the pump to the lower part of the carb.

Do i just disconnect the hose and plug the hole on the carb and start pouring premix?

Will the pump seize or will there be any side effects to this?

thanks!

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I'm going to say it depends... Depends on how much it's ridden. A simple thing to do would be to pull the pump apart, there are a couple gears, just take one out and put the pump back together. Then there's no more mechanical action. Even better is to buy/make a blockoff plate so you can remove the entire pump assembly. That's the route I go.

But, the depends part is that if it only gets ridden a couple hours every 2-3 weeks, you could just start premixing and leave the pump alone. I'd completely expect it would run a verrrrrrry long time before there was ever a problem from not running oil through it.

As for the carb side, yeah, just pull the hose and cap the fitting on the carb whichever way you handle the pump side.

With all that said, I've never worked on an RT specifically, but all the oil pumps I've seen are very similar to one another and the above suggestions would apply.

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There should be a hose from the oil tank to the pump, then another from the pump to the carb. What I would do is pull out the oil tank and all the lines, cap off the oil intake on the carb, take a short piece of hose and run it from the pump intake to the pump output. Drain the gas tank, fill with mix and go.

Ive seen it done where people just unhook the oil lines or simply run the oil tank dry. It wont hurt the pump any.

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I had one before that i just premixed with and never dis anything with the pump. All my friends mixed so we just used each others gas. The pump was operational as far as i know, then again i could have gotten lucky. I rode it all day 2-3 times a week.

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thanks for the feedback guys!

I went ahead and attached the inlet/outlet hoses outside the pump and removed the oil tank. Plugged the hole on the carb.

All seems well at this point.

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On my sled (fuel/oil injected two-stroke), the oil is also pumped to the crank bearings. I'd make absolutely certain that oil isn't going elsewhere before ripping it off.

Curious, but why are you removing the pump in the first place?

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Curious, but why are you removing the pump in the first place?

That's what I was wondering. There aren't many good reasons to do it.

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I removed the oil line and plugged the hole in the case on a pw50 and ran premix for years.

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i would just disconnect/remove the whole system, and plug the oil intake hole in the carb. makes the bike maybe a pound or so lighter, not tomuch of a difference iflosing weight is what you had in mind. or did your oil pumpget clogged? please give us some clarification

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On my sled (fuel/oil injected two-stroke), the oil is also pumped to the crank bearings. I'd make absolutely certain that oil isn't going elsewhere before ripping it off.

Curious, but why are you removing the pump in the first place?

removing it mainly for reliability and also most of my bikes are 2-stroke so its no big deal to pour in premix.

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i was gonna do it to my old tsr because that system weighed a ton! and because it was kind of clogged up and i didnt really care for it too much. kept it on and cracked my rad the next day, didn't notice and kept riding... the combination of both factors blew my top end to peices and little bits of piston got in my bottom end. had to let it go for 500 bucks in that condition, really sucked so if i got another injected bike i would probably just mix. wouldnt want that again.

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myself i have an ol 73' f-7 kawasaki

oil injection too

important note here...: my bike needs the injection to feed the crank bearings

these systems are technically superior to pre-mix and are removed way too candidly over unfounded fears

my thoughts lay in reduced production/model costs eliminated a very sound technology

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myself i have an ol 73' f-7 kawasaki

oil injection too

important note here...: my bike needs the injection to feed the crank bearings

these systems are technically superior to pre-mix and are removed way too candidly over unfounded fears

my thoughts lay in reduced production/model costs eliminated a very sound technology

This. The only reason to even consider disabling it is after confirming it's really dead and that's so rare it's not worth discussing.

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The pumps Yamaha uses are stone axe reliable. Of course someone will chime in with a story of carnage but the pump on my 27 year old RZ350 still does the job. 40K miles of no worries and many of them racing. No reason to ditch the pump.

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On PWCs used in a marine environment, going to premix is a good idea. But oil injection systems on those little motorcycles are stone reliable. No need to block it off, IMO.

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Hey, I own a rt100 1994 and this is what I did, start at the oil tank, through the tube, into the pymp, the oil goes through the crank and back out the output, but at the output, cut the hose and block the carb input, add lengthen to the hose and go right back to the oil tank, cut a hole in the lid and silicone, so the oil just goes round and round throught the crank, put premix in (35:1 works good) and your done!

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Hey, I own a rt100 1994 and this is what I did, start at the oil tank, through the tube, into the pymp, the oil goes through the crank and back out the output, but at the output, cut the hose and block the carb input, add lengthen to the hose and go right back to the oil tank, cut a hole in the lid and silicone, so the oil just goes round and round throught the crank, put premix in (35:1 works good) and your done!

??????????????

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Let's do a bunch of extra work, for absolutely no benefit and while we're at it, make an attempt to starve the remainder of machine of lubrication. All this to avoid filling one tank every 10-15 hours.

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Keep the oil injection when ever possible. Properly adjust it.

But if you must remove it, you must also rejet the carb as it will run very lean. Remvoe the pump from the bike, locate (or have made) a cpa to cover the pump mount. Store the pump and tank.

I never removed the pumps, even back in the early 70's when it was 'kewl' to remove them.

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