re-sleeving is not required. thats a lot of carbon.... rings are prolly shot. it is also possible the bore it out of round and/or over size as well. you can measure it & see. just using new rings might fix it but I have doubt. when the rings wear, it also wears the piston grooves. it might fix it for a while, but will be a burner again pretty soon. to be sure of a good fix that will give the bike years of life I would go to the proven aftermarket parts rather than a Kawi oversize piston. either the 685 or 688 will work fine as long as the bore job is done by someone that knows how to do it. going to the 685 leaves room in the future to up to the 688 if needed (like 40k miles down the road). the bottom end is all roller bearings... they need very little oil. look the big end of the connecting rod over very carefully... if it has any "blue" from heating then it's no good & not worth messing with. if it looks normal I wouldn't worry. yes, clean the oil pick up screen. take the oil pump apart & check it close. if the intake valves are bent, the ex valves were probably closed & are OK. klr valves can make a lot of miles I have rescued a few that ran low on oil & had success. flush everything with kerosene, install good parts & ride on. don't use the Comtech gaskets, sometimes they leak... the Kawi ones work
How low? Still in the sight glass but low, or have to lean the bike to see it in the sight glass, or I drained it and less than a liter came out?
I am at 40K on the 685 and it is still great! No oil usage that can be noticed! Feels the same as when it was put in! That is good news for those considering the change. It was a unit bored by Cary. I installed Cometic Gaskets. No leaks or weaping whatsoever.
ymmv.... I chose 40k at random... should last that long no problem if everything was fitted correctly. as for the comtec gaskets... I read they had leak problems literally the day after I bolted the jug back on my bike. what the heck, I know I put it together right... I am a pro.. I do this stuff all the time.... run it. it lasted maybe a week and started weeping (base gasket). I also have a friend with a comtec leaker... same story, done about the same time. just luck of the draw? maybe they had a bad parts run? anyway there was a rash of them at the time... maybe now it's fixed? (this was about 4 years ago) whatever, someone screws me I am wary
Good info with the 685 now and 688 later. What do you guys recommend for boring out the block from your experience? Should I budget shipping to someone who has done this before, or would a decent shop locally be able to bore it out? Currently working in Omaha if anybody locally has a shop recommendation. How much should I budget for having it bored? Also, good info on the bottom end with the roller bearings. Will take a close look at the connecting rod. Should I plan on replacing the oil screen, or just clean it out? With flushing the engine out with kerosene, is there any method to the madness, or just dump the kerosene in the top of the block with the piston out and let it all flow out the oil drain and then let air out for 24 hrs? 1 gallon of kerosene? Where can I buy some? *Said with head hanging low * Could barely see the oil in the sight glass when leaning bike heavily. Rode a lot of highway around the time of the problem, which was uncharacteristic. Have always taken care of my rides and understood the importance of maintaining oil, but I guess you don’t *truly* understand until you run an engine dry. Going to glean a lesson learned from this one and move on with eagle-eyes on oil levels every time I take a rest.
Hey it happens. I was only asking to make sure there wasn't some other issue that caused this. If you had said the oil was "low", but still visible in the sight glass when the bike was vertical I'd say there's another problem you should be looking into before buttoning the bike back up. But since you've got to lean the bike way over to see any oil in the sight glass then it definitely is a low oil issue. I'd drain it and measure the amount that comes out just to be more specific on how low the oil level got. I once got back from an extended highway run on my KLR with no oil visible in the sight glass, but a slight lean of the bike showed some. I dodged a bullet with that one. I can't remember what the difference is between the bottom and top of the sight glass is on the KLR, but on my Strom for example, it's only 1/2 a liter between the low and high marks. Being half a quart low isn't the end of the world.
Checked out the oil screen and removed the cylinder jig last night. Still need to check oil pump. About ready to order parts. What else should I consider doing while I am in here? So far I am thinking about installing the "doohickey" and also considering polishing the head up a bit. Removing water pump housing and impeller. No gasket here like I expected as shown on Mark Net guide. Was this gasket removed in '08? Side cover. Gasket wasn't even close to being able to be salvaged. Is this just called a right side case gasket? I will need a new one. Oil screen wasn't half as bad as every other one I have seen around ADVrider. Guess that's a good sign there wasn't gasket garbage all over. Pretty clean in there. Sleeve off. Piston seemed in good shape. Leaning towards replacing with a 685. Are these valve grooves in the piston normal? Cylinder jug looks in decent shape. Will look better bored out to 685 Inside the piston. Is that color normal? You all said to check out the rod for blue and signs of heat. I didn't see any, does it look alright to you guys?
Peace of mind on that screen, good work. Valve reliefs in the top of the piston are normal, except for the shiney ones where the valves touched. Rod looks good, no bluing...we see that a lot in the XRR thread and it's pretty obvious when you see it. I think the 688 is the go to kit right now, talk to Mike, he'll set you up with a doo kit and gaskets too.
I've got a head and valve assembly and a 685 big bore kit on the way. Stay tuned, should be able to start wrenching this weekend. :dllama
I just tuned into this thread and I may be a little late. These guys can repair heads, I wonder if they can handle that type of cam bearing damage. http://www.mt-llc.com/ Might be able to help the next guy with head problems.
Regarding the colour of the underside of the piston - Gordon Jennings wrote years ago in a "Cycle" Magazine article that he used to jet his racebikes (TZ Yamahas) by the colour of the underside of the piston as it was a good indicator of heat. I recall he said that the underside could be as "black as an AMA race officials heart" and it would be ok, but as soon as the oil began to char, a siezure was not far off. Jennings, Kevin Cameron, Cook Nielson - are there any motorcycle writers of equivalent talent these days?
Brief thread hijack, and stroll down Memory Lane: I bought the first issue of Cycle World; became an avid reader through the early 1960's . . . I think it may have been Jennings, writing a review of, I think, a JAWA, who said: "This motorcycle could fall off a cliff, and the only damage suffered would be to the rocks below." Such inspired prose remains rare among practicing moto-journalists today; perhaps a function of the advertising revenue-driven publishing industry now extant. Dexter Ford, a competent and prolific motorcycle journalist, was fired after publishing a 2005 article containing test data indicating helmet cost and protection were not necessarily proportional. A mere coincidence, high-end helmet vendors advertised heavily in the magazine? Maybe so . . . And now, we return to our regularly-scheduled program!
I'd expect so - it is indicative of the amount of heat going into the piston crown. 4 strokes are a little better off in that there can be a steady feed of oil to the underside of the piston to carry away heat.
Alright everybody, I've got a replacement head and top end in hand thanks to @larryboy! Just lacking the 685 and doohickey kit from Eagle Mike and I'll be wrenching! I want to open it up to you all for best practices with putting the engine back together. I've got most all of the information that I need to perform the work, Cam alignment etc, correct torque values etc. I have put a good amount of time and money into this thing to date and I want it to pay off with a solid build that will rip for years without leaking! Let's hear your best practices, lessons learned. I've been reading through the Kawi Repair Manual and it seems fairly straightforward, but I do have a couple questions. The service manual doesn't spec the cam chain specifications...what is within tolerance? Is there any trick with installing the gaskets? Should I apply a coat of a sealant or anything with the gaskets for a solid seal, especially the head gasket? Also, when the manual says "apply a non-permanent locking agent", can I read this is Loctite? How attentive do I need to the specific parts that the manual calls for to apply molybdenum disulfide grease or molybdenum disulfide oil agent? Is there a difference between the 2? Do I really need to apply this? Getting excited to get her running again!
Cam Chain - IMHO cam chains should be replaced at rebuild time, cheap insurance. Maybe not as critical with a low HP engine like the KLR but this must be done on CRF's, YZF's etc. As you said, you have invested lots of cash into this project, and given the KLR's doohickey history a new chain would be a good investment. Gaskets - If the gasket surfaces are clean and not gouged, and you are using good quality gaskets there is no reason to use sealants. A sealant can cause trouble if used incorrectly. A leak free seal is more affected by prepping of the surface than the gasket used. Make sure the sealing surfaces are spotless, grease and oil free, and smooth. Try not to take any metal off while cleaning the old gasket off. It might be worth while to invest in 3M roloc bristle buffers, http://www.amazon.com/3M-07527-Roloc-Bristle-Grade-Yellow/dp/B000FW2M2C. They come in different sizes. Non-Permanent Locking Agent - Yup, good old blue Loctite. I recommend trying to track down Loctite 243 instead of 242. 243 sets up better in oily situations and seems to set better in aluminum. Remember it takes 24hrs for loctite to cure. Moly Grease/Oil - I assume this is for the cams/cam journals? You could definetaly invest in some assembly paste with moly for these items. I have had good luck with using the same oil that I will have in the engine for break in but it doesn't hurt to go the extra step.
Use assembly lube/moly on new cams for break-in, it's not needed on parts that have been run already. I just dump oil all over the top of the cams and journals, then assemble. The only place that the factory uses loctite on a KLR engine is the one short bolt that holds the cam chain noise cover down...the one you really, really don't want to drop. I've never seen a worn out cam chain on a KLR, don't sweat that, just put one on and time it properly. All gaskets installed dry, including the valve cover, rarely the little round parts of this gasket will need a little RTV to get them to hold still so you can get the cover back on.
1. I dont know where you are getting your 685 from. Go to the Schnitz website and down load the assembly instructons written by Cary for the 685. It also has clear instructions about sealant placement. I used the Cometic gaskets and sealed as suggested and 40K miles later not a drop or weep has occurred. Yamaha Bond or Honda Bond ( available from their car dealers too). 2. Any non-permanant thread locking. 'Loctite', 'Permabond' are brand names - use what is available. 3. I mix moly based grease with oil if the oil version is called for. Moly is a high pressure lubricant that will wash out when the motor is fully running - and it will not affect your clutch!. Enjoy the wrenching and the ride!
