
Spitting oil,
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Spitting oil,
One last question,the right side smokes a lot and opinions suggest an oil seal,would oil spitting out the muffler confirm an oil seal problem, 

CB360T
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Re: Spitting oil,
Sounds highly likely Alan.
Many years back I was following my pal in my car. He was riding his RD400 with a blown seal, and the screen of my car became so covered in the mist of oil from his exhaust, that I had to stop and clean the window, as the wipers were just smearing it.
Many years back I was following my pal in my car. He was riding his RD400 with a blown seal, and the screen of my car became so covered in the mist of oil from his exhaust, that I had to stop and clean the window, as the wipers were just smearing it.
Keeping old 2 strokes alive !
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Re: Spitting oil,
Which bike has this problem? Does it run good?
If its a T250/T350/GT250, you can check the tranny oil level by looking down the oil filler opening.
Can use something like a screwdriver as a dipstick to accurately check for oil consumption.
If its a T250/T350/GT250, you can check the tranny oil level by looking down the oil filler opening.
Can use something like a screwdriver as a dipstick to accurately check for oil consumption.
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Suzuki:
GT750 2x75
GT550 72 & 75
GT380 72
T500 69 project & 73 project
T350 69 & 71
Honda 85 CB650SC & 86 CB700SC
09 Triumph Bonneville SE
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Re: Spitting oil,
I put socks on my exhausts to stop the oil mess on the back of my 74 GT550 after a long hard ride through the mountains. The pump is set as low as it can go and I don't run through much 2 stroke oil.
My transmission oil level also stays constant.
My transmission oil level also stays constant.
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Last edited by Ebayru on Sat Jan 21, 2017 8:14 pm, edited 2 times in total.
- Alan H
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Re: Spitting oil,
It would depend how many starts and short runs you did before the long run. Could just be residual crap in the silencer(s). Hang them up and drain them and try again.alanr wrote:One last question,the right side smokes a lot and opinions suggest an oil seal,would oil spitting out the muffler confirm an oil seal problem,
What do the plugs look like? Black & oily?
But checking transmission oil before and after a run is a good way to check if you're burning it.
Think of how stupid the average person is, then realise that half of them are more stupid than that.
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Re: Spitting oil,
All 2 strokes, even in good working order will spit oil to a small degree. Especially during idling. If yours spits a lot. It could be one of a few reasons. Today's injector oil is a lot thinner than the oil originally designed for these bikes. Therefore I strongly feel that it's a must to dial the pump down a little. Using today's injector oil at factory recommended pump setting spits a ton of oil. That's where I would start. You'll notice when you dial the pump down a little the bike won't excessively smoke at start up and less oil will be spitting all over the exhaust, etc. Regardless, that's what all 2 strokes do. They're all impossible to keep the tail end of the bike clean if they are ridden often enough. But, excessive oil blow by can and needs to be addressed. Otherwise, the bike will have heavy carbon build-up and the fuel mixture will be leaner due to more oil than the fuel mixture requires. A lot of idling will also build a lot of carbon in unwanted places. Exhaust ports, pipes, piston tops, etc. Heavy carbon build up creates a couple problems in itself. Easy to clean those areas. Perhaps that needs addressed too.
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Re: Spitting oil,
Question: can you leave the socks on while riding? 
Mike

Mike
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Re: Spitting oil,
I do Mike, or my feet get cold. 

Think of how stupid the average person is, then realise that half of them are more stupid than that.
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Re: Spitting oil,
Yes, the socks are on the exhausts during riding because that's when the oil spits.
The oil messiness worsened with the addition of the sidecar probably from the increased load and the altered airflow which probably creates a low pressure area at the back of the bike which brings the oil back onto the bike.
The oil messiness worsened with the addition of the sidecar probably from the increased load and the altered airflow which probably creates a low pressure area at the back of the bike which brings the oil back onto the bike.
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Re: Spitting oil,
You'll just be using larger throttle openings which pumps more oil into the engine. Then shutting the throttle but the engine is still running fast which still pumps more oil through. You're actually using the bike harder than designed, so everything works harder. I think the oil system is doing exactly as it was designed and looking after the engine. You need to go on some longer runs to get rid of the excess . There dhould be drain holes under the front part of each silencer - make sure there hasn't been screws put in them.
Think of how stupid the average person is, then realise that half of them are more stupid than that.
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Re: Spitting oil,
My bike has no drain holes at the front of the silencers. There are holes in the back for accessing the baffle securing screws only. A lot of the oil will come out of those and run back onto the pipes. I do plenty of long hard runs with the rig as I live in the mountains of Western North Carolina. I think most of the problem is that the synthetic 2 stroke oil has such a high burn temperature that it doesn't burn like the older oils did and it comes out the back as dirty oil. I have the same spitting with my Yamaha RZ350 except that the oil spatters riders behind me instead of messing up my bike. I have reduced the oil pump output on both bikes. The GT550 has the cable set as low as possible.Alan H wrote:You'll just be using larger throttle openings which pumps more oil into the engine. Then shutting the throttle but the engine is still running fast which still pumps more oil through. You're actually using the bike harder than designed, so everything works harder. I think the oil system is doing exactly as it was designed and looking after the engine. You need to go on some longer runs to get rid of the excess . There dhould be drain holes under the front part of each silencer - make sure there hasn't been screws put in them.
Last edited by Ebayru on Sun Jan 22, 2017 12:23 pm, edited 1 time in total.
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Re: Spitting oil,
Check the marker lines on the pump body and rotating quadrant for alignment. (behind the chrome pump cover.)
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Re: Spitting oil,
Yes, I've done that. I have the pump set for the least possible oil output.Alan H wrote:Check the marker lines on the pump body and rotating quadrant for alignment. (behind the chrome pump cover.)
Interestingly, a few months ago I discovered that the oil pump cable was broken. I remember thinking that the bike was not smoking under load. There are some long, steep grades that I drive consistently and I had previously seen smoking on those grades. I must have been driving for months with the broken cable. There were no obvious consequences of the pump not responding to throttle opening. The bearings get constant flow so they wouldn't be affected and I'm willing to wager the cylinders were also not affected, but I obviously wouldn't know for sure without at least pulling the head.
Is anyone aware of a practical way to reduce pump output other than by the cable adjustment? The Yamaha pumps also have a stroke adjustment.
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Re: Spitting oil,
These arent like Yamaha pumps. Cable is the only adjustment. Personally, I turn mine down far as i can. The motor still gets plenty of oil because the pump is still fully open at 3/4 to full throttle. These bikes idle with too much oil if set to factory recommendation using todays injector oil. Thats the only oil input you change by turning down the pump. If you read the plugs you can verify thats its getting too much or too little oil.
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Re: Spitting oil,
I knew they don't have the stroke adjustment like the Yamaha pumps. I was hoping that someone had successfully figured out a hack for the Suzuki pumps. The socks are doing the job, albeit dorkily.pearljam724 wrote:These arent like Yamaha pumps. Cable is the only adjustment. Personally, I turn mine down far as i can. The motor still gets plenty of oil because the pump is still fully open at 3/4 to full throttle. These bikes idle with too much oil if set to factory recommendation using todays injector oil. Thats the only oil input you change by turning down the pump. If you read the plugs you can verify thats its getting too much or too little oil.