I stepped away from my Vstrom a couple years ago because I wasn't using it the way I had intended. Went with a Triumph Speed Triple awesome bike and don't ever see me moving away from her. So along comes an opportunity for me to do a week long back country ride through Utah. It sparked the interest in a dual purpose bike. I decided I was going to do it on the cheap so the hunt begun for the "right " bike. Wasn't looking for anything special just started the hunt. I spent a couple weeks on Craig's list and finally found a 1990 DR650 in my price range. I went to look at it and all looked good it started after the second kick from dead cold. There is something appealing to me about a bike you have to kick to bring it to life. Everything worked and was factory. I was told the engine had recently been gone through, he had all the notes and receipts to show what work had been done. There was only 800 miles since the work was done. So we seal the deal and I take it home. The weekend showed up and I decided to take an easy day trip with some black top and some forest service roads. The total miles were 230ish some 65 mph stretches with it running around 4 grand on the tack. All went as planned no reason to think there was anything wrong at all. Next morning was Sunday and the family were all stuck in bed so I though it was a good time to sneak the bike out and put some more miles on again. Checked the oil and it was down to the point it wasn't showing up in the glass window. Side note I did the new to me oil change as soon as I got it home. It took about 3/4 of a quart to bring it back to the top line. So now the oh no moment started to set in. Well in into this about 500 miles and the oil usage would keep me from ever having to change the oil, its will be a check the gas and fill the oil program if I don't do something well tonight was the do something moment. http://s1302.photobucket.com/albums/ag127/tpruitt72/?action=view¤t=IMG_0043_zpsfd9077b9.jpg The head comes off and see heavy carbon and then move the piston down and see this.... http://s1302.photobucket.com/albums/ag127/tpruitt72/?action=view¤t=IMG_0044_zpsbac527e6.jpg And this http://s1302.photobucket.com/albums/ag127/tpruitt72/?action=view¤t=IMG_0045_zps576819f2.jpg The jug had to come off and and look at the piston... http://s1302.photobucket.com/albums/ag127/tpruitt72/?action=view¤t=IMG_0047_zpsc9061059.jpg The piton was galled so badly that it had the oil control rings frozen in place so there is my problem. Not sure how the builder or owner did the start up or what oil he chose to use but I'm now in the middle of a rebuild. Luck of the draw my Brother is a great engine guy and does it for a living so the brown santa will be dropping him off a couple of boxes this week. He's going to go through the head at the same time. Updates to follow.
I pretty much only buy low mileage machines that are stock engine-wise, and the engines have never been opened. It seems like 9 times out of 10 if an engines been opened, and even if the owner has a stack of reciepts from what he claims is the best shop on the planet, you end up with a poorly rebuilt money pit. Nowadays the factories do the best job of putting an engine together, everything else is usually second-rate. The art of engine rebuilding is vanishing.....
Seems we all need to learn the hard way at least once. For me it takes a while. I have the time and I trust in my brothers skills as an engine builder so let the adventure begin. I'm in this bike for little to nothing, it's going to take a bit to be in the money pit category. Have to say though I went and sat on a new KTM 500 yesterday, nice bike I just don't see $10,000 in that bike. So if I end up dropping a couple grand to get this DR where I want it I'll be way ahead.
I think I am one of the lucky one's. Two years ago I bought a 2002 XR650L motor off E-Bay out of Mississippi. Owner said it had a complete top end rebuild at a local Honda shop & had been run 3,000 miles since. He had a buy it now price of $1000. I bid on it at the end & got it for $500. Had it shipped to me in an old plastic tub in less than a week. Put it in my 1995 XRL & over 7,000 miles later it still runs like a top. You just never know?
Okay got the measurements back and it was just too tight. There was only .0019 clearance between the cylinder and the piston, need .005 on an air cooled single. Things get hot and expand and there needs to be a little more room. The cylinder was not scored just had smeared piston on it. The piston is trash just waiting to hear how badly the cylinder in out of round hoping for a round hole. Waiting on parts hope to be back up and running in a couple of weeks. Work has me traveling for the next couple weeks so no big deal. My brother can't believe it didn't just lock up. Something to be said for synthetic oils I guess. More to come.....
DR's are great bikes.....at least now you're going to have a new engine in a great bike for a great price....thats pretty hard to beat Nope you really don't know, but there are still some honest folks and good shops out there....congrats on the new swap in motor for 500 bucks you lucky bastid
If it makes you feel any better I have a 91 that did the same thing. Bought it in Feb. and it started burning 1 quart every fillup. I got a top end gasket kit and wiseco 1mm O.S. piston off amazon of all places and fixed it last month. There was heavy scoring in the cylinder and piston. Runs like a top now. Hopefully yours goes together just as well
Ah,Yeah, its good to not get too enamored sometimes with bikes,best make sure all the oiling parts are working right,if its seizing the piston, best see that the bore was done in a round shape or close to it,not tapered top to bottom or slightly oblong,really has to be round. Not a lot of guys know how to run boring bars anymore. If the rod or crank is loose that can show up as cylinder/piston problems. Also give some thought to that kickstarter,on a hot day,with people watching,it will at some point have it's way with you and sit there like a petulant child refusing to even pop. Ask me how I know this. It could be flooded,or there might be no gas in the combustion chamber,hard to say sometimes. Sometimes a cheap bike can be the most expensive.
Some times the lust clouds our vision for sure. I'm not sure how I would test the oil system without putting it all back together again. The connection rod is without play so I feel that I'm good that direction I think it was just to tight of a fit. When it had all that compression leaking by, it was easy to start when hot we will see when it is all healed up. You are absolutely correct about cheap bikes and anything else really. The list of lives lessons can be long for some of us. The internet keeps taking me to KTM's web page. I just can't justify the cost right now with two teens at home and a wife that needs to find a new place to call home. Again live and learn....
Okay all parts are now finished machined and here, now they can be put back together. Hope to have pictures to post and a bike to ride in the next day or two. Took a while to get the piston I needed and my brother decided to rebuild the head while he was waiting for the piston. We got luck in the fact that the hole was to small. Same sized piston went back in and the cylinder could be opened up to correct for the to tight of fit. more to follow....
Couple of things: a tight piston doesn't cause loss of oil. Oil is either leaked or burned. If they put synthetic in it right from a fresh rebuild it could have caused the rings not to 'set' and excessive oil blowby. Many ring manufacturers don't reccomend synthetic for the first 500-1000 miles. They do make some rings that can run synth. from the get go, but they are rare in motorcycles. Some people make the mistake of using a moly based lube for assembly which also causes ring problems. Non-detergent oil the the best on new rings. I think you did the right thing by opening the clearance up. It is odd though to see that much diffrence in the same size piston. Most piston manufact. take the piston measurement 90 degrees from the piston pin at the same height as the pin. If you measure the bottom of the skirt you will get a larger reading- but that is from a cam cut on the piston to help it align itself in the bore and quiet piston noise. Good luck- Hope you are riding this weekend!
The last rebuild was before I got the bike so I have no idea how or what was used to break in the work. You are correct, the fact that it was a little on the tight side didn't cause the oil burn off but when the skirt of the piston smeared onto the side walls it filled the oil control rings. I'm no engine machinist but my brother is and a pretty good one from others tell me, so I just handed it off to him and have him wave his magic wand. He send me some high zinc oil to break it in with so thats what I'll be using unless someone here says it will mess with the clutch plates. From what I understand (which is not much anymore) air cooled engines need more slop than a liquid cooled one does. Evan (brother) thinks the first guy just hadn't done many air cooled engines and set the clearances a little to tight. She all put back together just need to set the valve clearances tomorrow and then all will be known. Would have finished tonight but it was my turn to cook dinner.... Have to keep mama happy ya know.
Yeh, stuff stuck in the oil rings doesn't help much. Did you happen to look at the 2nd ring on the old piston? If someone put it in upside down it causes oil burn problems as well(if it is a dirctional ring). Piston clearance is set based on a couple of factors: piston material and cooling system. I'm guessing you put a forged piston in so I would say .005 is good. I wouldn't be affraid to run as much as .008 in an air cooled motor. Cast or Hyperutectic (spelling?) pistons don't require as much clearance. I don't know what material the stock piston is made of but they reccomend .0047 clearance. That is measuring the piston .8 (21mm) of an inch up from the bottom (not quite to the piston pin center line) I use the zinc additives (Lucas Break In) in v8 engines with flat tappet cams to try and keep cams from going flat. I have never tried it in a bike with a wet clutch...couldn't tell you one way or the other if it is a good idea or not.
The piston is long gone so I don't know if the second ring was in wrong. And to be honest I wouldn't know what I would be looking for anyway. But she lives again the valves are a little noisy my guess is they are a little on the loose side. Used .005 feeler to set the clearance, what a pain so I'm sure I missed something. It's amazing how much easier it is to kick through when your not dragging the piston. Will post some pics when I get back from Orlando.
