GT 750 L smoking more out of left pipe
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- T350guy
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- Country: Canada
- Suzuki 2-Strokes: 1977 GT 750
- Location: Tweed. Ontario. Canada
GT 750 L smoking more out of left pipe
When I first got the bike it did this and a new oil line was installed. This seemed to have solved the problem.
The GT ran fine since.
About 2 weeks ago I hit a deer on the way home from work at 12:45 am. The bike ended up on my leg But was right over . Lots of injector oil made it's way out.
In the week or so past I have fired it up and ran fine.Today was my first ride. I put on about 30 miles going to Town.
I noticed upon a moderate acceleration there was a FOG of Blue behind me all coming from the left muffler.
Head back out onto the Highway at moderate throttle the Blue haze continues. up a hill and it's a fog all from the left side..25 miles later I pulled into a buds place..have a look and the exhaust flange to air filter/side cover has splooge on it..After a cold
beer I Fire it up and weird the smoking seems reduced.
I take off hard and not much smoke..Tilt the mirror down to watch and very little smoke BUT the left side is smoking a Tad more.Climb up the BIG Hill towards home , open throttle to 7000 and look , very little smoke.
1.... could have a check valve stuck open?
2.... Could have oil poured into the left side crankcase after the accident and took that long ride to clear...
I also understand some 750's smoke a little more out the left side. Any reason Why?
Ian
The GT ran fine since.
About 2 weeks ago I hit a deer on the way home from work at 12:45 am. The bike ended up on my leg But was right over . Lots of injector oil made it's way out.
In the week or so past I have fired it up and ran fine.Today was my first ride. I put on about 30 miles going to Town.
I noticed upon a moderate acceleration there was a FOG of Blue behind me all coming from the left muffler.
Head back out onto the Highway at moderate throttle the Blue haze continues. up a hill and it's a fog all from the left side..25 miles later I pulled into a buds place..have a look and the exhaust flange to air filter/side cover has splooge on it..After a cold
beer I Fire it up and weird the smoking seems reduced.
I take off hard and not much smoke..Tilt the mirror down to watch and very little smoke BUT the left side is smoking a Tad more.Climb up the BIG Hill towards home , open throttle to 7000 and look , very little smoke.
1.... could have a check valve stuck open?
2.... Could have oil poured into the left side crankcase after the accident and took that long ride to clear...
I also understand some 750's smoke a little more out the left side. Any reason Why?
Ian
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Re: GT 750 L smoking more out of left pipe

I was out on my "A" model yesterday,at freeway speeds up hill,she was still making more smoke slightly more on the right,I'm not overly concerned by this,as she is running so well at the moment,all the baffles when removed,seem to be equally as wet with oil,something you could look at maybe..

Regards,
GT750Battleship.
GT750Battleship.
- T350guy
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Re: GT 750 L smoking more out of left pipe
I pulled the plugs last night and all 3 were running exactly the same a very light tan.
Today I fired it up and NO excess smoke from the left side.
I have spare octopus line with bad check valves...well ALL of them are bad. Decide to see if I could fix them.
I tried cleaning up the seat area. Lightly tapping the ball into place. No luck.still leaks..All the springs must be weak. They do seal when blowing into the valve BUT the oil flows out as fast as it goes in..lol.
Too bad there wasn't replacement check valves.
On the Kawasaki H1/H2 non serviceable valves I have managed to save all of them..weird that I couldn't with the Suzuki ones.
Today I fired it up and NO excess smoke from the left side.
I have spare octopus line with bad check valves...well ALL of them are bad. Decide to see if I could fix them.
I tried cleaning up the seat area. Lightly tapping the ball into place. No luck.still leaks..All the springs must be weak. They do seal when blowing into the valve BUT the oil flows out as fast as it goes in..lol.
Too bad there wasn't replacement check valves.
On the Kawasaki H1/H2 non serviceable valves I have managed to save all of them..weird that I couldn't with the Suzuki ones.
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Re: GT 750 L smoking more out of left pipe


Cheers,
GT750Battleship.
GT750Battleship.
- oldjapanesebikes
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Re: GT 750 L smoking more out of left pipe
Well - I wasn't the only one - many others have taken a run it this problem also - Chris (Coyote), Richard (TZ375) and Allan (Suzsmokeyallan) amongst them. I did do a write-up which is somewhere on this board and also at this link. Chris' idea of splicing in good ones for me personally has worked the best so far, but your mileage may vary.GT750Battleship wrote:Hi,in regard to the oil spider lines & check valves,Ian Sandy (oldjapanesebikes)has done a fair bit of work & investigation into them.

Ian
If at first you don't succeed, just get a bigger hammer !
If at first you don't succeed, just get a bigger hammer !
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Re: GT 750 L smoking more out of left pipe
T350, You are overlooking the fact that you already came across the answer: It gets better after a cold beer
The degree of change you wish to achieve may simply be proportional to the amount of cold ones you wish to imbibe 


Burt Munro + John Britten + Kim Newcombe + Ivan Mauger = Kiwi Street Cred
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Re: GT 750 L smoking more out of left pipe
Ian you could have had some extra oil pool in the bottom of the left crankcase well area from the accident. Its a pity you did not remove the SRIS valves when you first saw the excessive smoke to see what levels of residual oil came out of all three.
I would suggest you remove the three valves for a check of their movement and to see what amount of oil is still sitting in there, then monitor the smoke levels.
I would suggest you remove the three valves for a check of their movement and to see what amount of oil is still sitting in there, then monitor the smoke levels.
Two strokes, its just that simple.
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Re: GT 750 L smoking more out of left pipe
I'm not planning on riding it for a few days so yes I will pull the left SRIS valve and see what comes out..I did have them all out once before and they all worked fine.
Out for a ride to work on Friday , still smokes a bit but a lot cleaner..tilting the mirrors down I can see smoke rolling out from the left and right side. I did notice again a very slight spluge on the chrome air filter housing.
I'll pull the valve on Weds
Out for a ride to work on Friday , still smokes a bit but a lot cleaner..tilting the mirrors down I can see smoke rolling out from the left and right side. I did notice again a very slight spluge on the chrome air filter housing.
I'll pull the valve on Weds
- T350guy
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- Joined: Thu Sep 08, 2011 7:25 pm
- Country: Canada
- Suzuki 2-Strokes: 1977 GT 750
- Location: Tweed. Ontario. Canada
- T350guy
- To the on ramp
- Posts: 266
- Joined: Thu Sep 08, 2011 7:25 pm
- Country: Canada
- Suzuki 2-Strokes: 1977 GT 750
- Location: Tweed. Ontario. Canada
Re: GT 750 L smoking more out of left pipe
put a clean dish underneath for Tues afternoon til today (Thursday) there was just a few drops.
Guess it wants to leak when it feels like it..lol
Guess it wants to leak when it feels like it..lol
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Re: GT 750 L smoking more out of left pipe
Nothing too significant now being seen in that cup, but you did have a fair amount of smoke so most of the residue could have been burnt off by now. Thanks for the photo and update on the smoke.
Two strokes, its just that simple.
69 Suz U70
69 Suz T500
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74 Suz GTXVR project
75 Suz RE5
75 Suz GT750
76 Suz TS400
76 Suz GT750
81 Suz GSX1100
86 Suz RG500x2
88 Hon CR500
93 Hon CBR900RR
98 Suz GSF1200x3
15 Kaw Ninja H2
69 Suz U70
69 Suz T500
72 Suz GT750 cafe
74 Suz TS250
74 Suz GTXVR project
75 Suz RE5
75 Suz GT750
76 Suz TS400
76 Suz GT750
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- T350guy
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- Posts: 266
- Joined: Thu Sep 08, 2011 7:25 pm
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- Suzuki 2-Strokes: 1977 GT 750
- Location: Tweed. Ontario. Canada
Re: GT 750 L smoking more out of left pipe
While at a Vintage rally this weekend My son took my H2b out and I on the GT..He said it was smoking pretty good out the left side BUT on the way back it was a FOG behind me..frigging check valve must have stuck..
- T350guy
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- Joined: Thu Sep 08, 2011 7:25 pm
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- Suzuki 2-Strokes: 1977 GT 750
- Location: Tweed. Ontario. Canada
Re: GT 750 L smoking more out of left pipe
Recently purchased another oil line and today cleaned with brake cleaner then filled lines until all air is gone ..Now sitting up right..so far it holds oil.
..I'll leave for another 12 hrs and see..

- T350guy
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- Joined: Thu Sep 08, 2011 7:25 pm
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- Suzuki 2-Strokes: 1977 GT 750
- Location: Tweed. Ontario. Canada
- T350guy
- To the on ramp
- Posts: 266
- Joined: Thu Sep 08, 2011 7:25 pm
- Country: Canada
- Suzuki 2-Strokes: 1977 GT 750
- Location: Tweed. Ontario. Canada
Re: GT 750 L smoking more out of left pipe
As noted in the repair section the saga continues.
Going to plug the RH SRIS line to the left intake and see what happens.
The loss of tranny oil may have been due when I hit the deer and it lay over on it's side. After a 100 mile ride the level remains the same even after heavy smoking from the left side .
If it doesn't clear up then it could be the pump? or the LH crank seal?
I even turned the oil pump all the way down last night and no difference
Replaced the oil line that doesn't leak as I thought the second one I put in maybe the check valve stuck.
The GT smoked from the Left side when I bought it, replaced the octopus line and it cleared up.
Then I hit the deer . Week later I head into town and that's when it started to really fogged out the left and continues today.
Going to plug the RH SRIS line to the left intake and see what happens.
The loss of tranny oil may have been due when I hit the deer and it lay over on it's side. After a 100 mile ride the level remains the same even after heavy smoking from the left side .
If it doesn't clear up then it could be the pump? or the LH crank seal?
I even turned the oil pump all the way down last night and no difference
Replaced the oil line that doesn't leak as I thought the second one I put in maybe the check valve stuck.
The GT smoked from the Left side when I bought it, replaced the octopus line and it cleared up.
Then I hit the deer . Week later I head into town and that's when it started to really fogged out the left and continues today.