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DR650(780) some problems

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Not to say that i'm totally surprised being my first attempt at putting together a motor here but Ive developed a issue and not sure why.. after about 50 miles on the rebuild I've noticed a puff of white smoke after start when cold, but once i get the bike hot .. no smoke. Also, I've got a dribble of oil coming from the left corner of the head. specifically a drop of oil will form overnight on the lowest fin of the head form the bike leaning over on the stand.. any thoughts would be appreciated

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If it is dripping oil from the lowest fin of the head, then the head gasket is right there no? So my theory is your head gasket it messed up and I'd bet the smoke at start up is also related to that. Have you looked at the spark plugs?

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If it is dripping oil from the lowest fin of the head, then the head gasket is right there no? So my theory is your head gasket it messed up and I'd bet the smoke at start up is also related to that. Have you looked at the spark plugs?

yup.. sooty looking plugs..gonna re-torque the head bolts

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I had a similar leak a little while ago, but it turned out to be the exhaust valve cover. It was such a slight leak that the area under the valve cover and head appeared clean. The o-ring was replaced and problem disappeared. Before taking everything apart, I'd clean it thoroughly and dust it with a little corn starch or something similar and run it to pinpoint the leak.

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I had a similar leak a little while ago, but it turned out to be the exhaust valve cover. It was such a slight leak that the area under the valve cover and head appeared clean. The o-ring was replaced and problem disappeared. Before taking everything apart, I'd clean it thoroughly and dust it with a little corn starch or something similar and run it to pinpoint the leak.

I like the corn starch Idea.. ill give it a shot

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Part # for the valve inspection o-ring is 11177-44B01 , you'll need 2 of them if you replace em. Also note, torque them down appropriately as the stock bolts are very week! I broke mine pretty easily over torquing it and had to pull out the bolt-out kit Grrr.

If it is truly leaking from the bottom part of the cylinder head you might need a new head gasket; 11141-32E00 (less than $30)

If not leaking from the valve cover inspection cap nor the base of the cylinder head then it is a gap between the cylinder head and valve cover, in that case put down a fresh bead of hi-temp RTV.

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I got my 780 kit this August and it included a 3 piece head gasket. 3 stamped metal gaskets rivited together with the instructions to put them on grease free, not even finger prints?? Your gasket looked different. I will put a high temp silicon around the chain well .

I assume you got the same instructions as I did??

I did check my head for flatness and it was right on. YOur head is a new rebuilt since it has the big valves so it should be flat.

good luck and I am glad you went first. I am putting off final assembly until the warmer weather. We are locked in snow so my bike is in no hurry.

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I got my 780 kit this August and it included a 3 piece head gasket. 3 stamped metal gaskets rivited together with the instructions to put them on grease free, not even finger prints?? Your gasket looked different. I will put a high temp silicon around the chain well .

I assume you got the same instructions as I did??

I did check my head for flatness and it was right on. YOur head is a new rebuilt since it has the big valves so it should be flat.

good luck and I am glad you went first. I am putting off final assembly until the warmer weather. We are locked in snow so my bike is in no hurry.

Mine was the stamped copper gasket.. I'm thinking the head bolts loosened up..or need to be re-torqued

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My guess is also head gasket. Puff of smoke, sooty plugs. Both indicate oil getting into the combustion process. An external oil leak wouldn't cause those symptoms. And another guess is that you would need to get the head gasket from the vendor of the big bore kit, correct?

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My guess is also head gasket. Puff of smoke, sooty plugs. Both indicate oil getting into the combustion process. An external oil leak wouldn't cause those symptoms. And another guess is that you would need to get the head gasket from the vendor of the big bore kit, correct?

The stock gasket would hang into the combustion chamber. YOu have a solid copper head gasket and I have a multy layer steel one rivited together. Both from Procycle?? I wonder which is the better one and why the 2 different gaskets??? Jeff???

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The stock gasket would hang into the combustion chamber. YOu have a solid copper head gasket and I have a multy layer steel one rivited together. Both from Procycle?? I wonder which is the better one and why the 2 different gaskets??? Jeff???

and ur head has a bigger radius then the base gasket? what ur describing sounds like the stock base gasket..maybe the copper one costs less money?? no idea.. thats some things you should ask procycle.. if it were me I'd be really curious.

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My base gasket is the stock one. It has a suzuki part number on it with their sticker. It is exactly the same one as I took off the old motor. With the big bore kit the bottom of the new sleeve fits the stock gasket.

The head gasket must be larger and it is not suzuki. It is two metal gaskets, thin metal with a third what looks like aluminum sandwiched between the two metal gaskets with raise lips around all bolt holes, around the cylinder and the cam chain well. Torquing the head would flatten this raised lips and hopefully seal everything.

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Yeah, i know it would hang into the combustion chamber, but wasn't sure if the other gentleman knew. And i've got a question; If i were to go with the big bore kit and wanted to assemble the motor with clay in the valve pockets to check for clearance, would i be able to re-use the new-but-now-flattened-but-not-run head gasket, or would i need to have two to start with as the one used for the claying of the piston would be toast? In the past i have always cleaned an old head gasket and used it to clay a piston, never have re-used a new one and don't know if it is advisable.

Thanks.

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Yeah, i know it would hang into the combustion chamber, but wasn't sure if the other gentleman knew. And i've got a question; If i were to go with the big bore kit and wanted to assemble the motor with clay in the valve pockets to check for clearance, would i be able to re-use the new-but-now-flattened-but-not-run head gasket, or would i need to have two to start with as the one used for the claying of the piston would be toast? In the past i have always cleaned an old head gasket and used it to clay a piston, never have re-used a new one and don't know if it is advisable.

Thanks.

I was told that you can re torque the copper gasket

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