Engine smoking left side only

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URALNUT60
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Engine smoking left side only

Post by URALNUT60 » Sun Sep 15, 2019 4:48 pm

500 miles on 650 rebuild 97 Ural bike rings seated after50 miles no smoke after that all of a sudden the other day when bike under load going down the road left side putting out white smoke, at idle not, blip the throttle no smoke, sitting at red lights and when leaving off throttle no smoke, but going through the gears looks like a bug sprayer, just the left side! Suggestions on were to start? Thanks for anybody's input!

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Lokiboy
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Re: Engine smoking left side only

Post by Lokiboy » Sun Sep 15, 2019 5:25 pm

White smoke I believe means burning oil. Since you just put on rings, I’d think something is amiss
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Re: Engine smoking left side only

Post by 4REICH » Sun Sep 15, 2019 5:39 pm

I will be watching this post. My 650 solo also has this intermittent problem. I thought I had cured it by adjusting the float height and replacing the valve. I also took the head off to see that the oil return passage wasn't blocked. I thought it was conquered until I had to skid to a stop avoiding one of those crazy female drivers who was gunning for me. After disaster was averted the left side smoke reappeared. Disgusted I parked the bike for a month, I started it up last week no smoke but the rim had sliced into the tube valve stem.
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Re: Engine smoking left side only

Post by URALNUT60 » Sun Sep 15, 2019 6:51 pm

Will check the simple thing as in carb but have a suspicion rings got glazed, would proper thing be to run a hone through cylinder to break glazing 180 grit, then a new set of rings? Everybody's thoughts?

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Re: Engine smoking left side only

Post by Lmo » Sun Sep 15, 2019 7:14 pm

Glazed, or might have broken a ring. You might try doing a compression check; quick to do.

What's the plug look like?
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Re: Engine smoking left side only

Post by Tomcatfixer » Sun Sep 15, 2019 7:17 pm

Worn valve guide(s)?
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Re: Engine smoking left side only

Post by URALNUT60 » Sun Sep 15, 2019 8:50 pm

Tomcatfixer guides were checked by machine shop during rebuild when seats were lapped not that something could of happened, bike runs good just smokes left side no mosquitos in site! Lol, compression check to start, then have guides checked, what is the lowest number compression that I should see? Just changed oil and checked valves they are spot on

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Re: Engine smoking left side only

Post by Tomcatfixer » Sun Sep 15, 2019 9:34 pm

what is the lowest number compression that I should see?
This is more of a Claus or Cateyetech question, but I would investigate a pressure lower than 120~130psi. My 2015 cT typically has 150psi. It'll be interesting to see if your left cylinder has considerably lower pressure than your right one.
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Current rides:
2015 Ural cT "Mobile Chernobyl", 2001 Ural Patrol "Little Red Bear", 1999 Ural Tourist "The RPOC", Mid-Nineties Ural Tourist "The Heap", 1994 Honda VFR750F

Previous rides:
2007 Honda VTR1000 FireStorm (Super Hawk in U.S.)
2001 Buell Blast! - - - - - - - 2005 Yamaha FJR1300
1993 Honda CBR600F2 - -1984 Yamaha FJ1100
Two different 1986 Yamaha FZX700S Fazers

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Re: Engine smoking left side only

Post by URALNUT60 » Mon Sep 16, 2019 7:11 am

Tomcatfixer will post #s when I do the test, curious myself

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Re: Engine smoking left side only

Post by RC20 » Mon Sep 16, 2019 2:21 pm

White smoke is water, oil should be a bluish color.
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Re: Engine smoking left side only

Post by Tomcatfixer » Mon Sep 16, 2019 3:07 pm

RC20 wrote:
Mon Sep 16, 2019 2:21 pm
White smoke is water, oil should be a bluish color.
Well, there you go, 'Nut.
RC called it.
You have a water leak! :lol:
- Chad

Gordonsville, Virginia, USA

Current rides:
2015 Ural cT "Mobile Chernobyl", 2001 Ural Patrol "Little Red Bear", 1999 Ural Tourist "The RPOC", Mid-Nineties Ural Tourist "The Heap", 1994 Honda VFR750F

Previous rides:
2007 Honda VTR1000 FireStorm (Super Hawk in U.S.)
2001 Buell Blast! - - - - - - - 2005 Yamaha FJR1300
1993 Honda CBR600F2 - -1984 Yamaha FJ1100
Two different 1986 Yamaha FZX700S Fazers

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Re: Engine smoking left side only

Post by Wildhorse Cafe » Mon Sep 16, 2019 8:03 pm

It could be vapping. Cannabis oil will solve that.
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Re: Engine smoking left side only

Post by URALNUT60 » Tue Sep 17, 2019 4:41 pm

Left side 50 right side 60, squirted oil in left than right cylinder numbers did not change, watched a video that stated when squirting oil in cylinder if numbers changed its rings if not look at the valves, people's thoughts?

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Re: Engine smoking left side only

Post by Lokiboy » Tue Sep 17, 2019 5:00 pm

URALNUT60 wrote:
Tue Sep 17, 2019 4:41 pm
Left side 50 right side 60, squirted oil in left than right cylinder numbers did not change, watched a video that stated when squirting oil in cylinder if numbers changed its rings if not look at the valves, people's thoughts?
Did you have the throttle wide open during your test? If you did, then there is a problem. If you didn’t then the numbers basically double, so, IMHO between 100-120 for an engine that old I would consider ok.
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Re: Engine smoking left side only

Post by rivers » Tue Sep 17, 2019 5:05 pm

First thought after your compression test....did ya do the test correctly? Tested with carb throttle plates wide open? Those are some really punky numbers and if correct you'd notice more running probs beside just smoking exhaust. Barely have any power at all.
2nd thought: what type of gauge used? The screw in type or the rubber tipped press/hold to the hole type? The later are notorious for losing the seal during testing.
Doing a dry then wet comp test is good for determining bad rings or valves on most motors (near vertical cylinders). Not convinced how well it works on boxer cylinders with the pistons laying on their side.
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