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Discussion Starter #1 (Edited)
I'm at just shy of 20K miles and am going to put a 685 kit in the beast. I'll chronicle it here.

This afternoon I tore the thing down; it was pretty straightforward. There are a couple of hidden fasteners that keep the head from coming off, the most insidious being a small bolt down in the cam chain galley. Referring to the manual keeps the frustration to a minimum.

I decided to measure the bore to see how tapered and out-of-round it was.

I measured it in the for and aft diameter and 90 degrees to that, taking a measurement at the top, middle, and bottom of the cylinder. I set the top for and aft measurement as my zero point.

_____________For/Aft Axis____Right/Left Axis

Top__________ 0.0000"_______ -0.0007"

Middle________+0.0005_______-0.0010"

Bottom________+0.0008_______-0.0009"

Thus, the max out-of-round is 0.0017", at the bottom of the cylinder.

The max taper is along the For and Aft Axis at 0.0008".

There was no scuffing or scoring on either the piston or the cylinder. The piston showed a very slight bit of wear on the skirt, while the cylinder is smooth - no crosshatch left. Pretty much what you'd expect to see, I think. The ring gaps were properly oriented.

The head and cylinder are packaged up and ready to go off to M-Tech up in Bend, Oregon tomorrow. they will bore the cylinder, port the head, install big valves, hopefully set the valve clearance, and ship it back to me in abut 10 days.


T
 

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Cool! I'm no machinist or anything, so I'm not sure but 0.0017 isn't that bad for out of round is it? Was your bike an oil burner? I eventually hope to do mine as well, it's not really using oil but I rode a 685 of a friends and I liked the extra "kick" :)

Cheers,
Stew
 

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Cool! I'm no machinist or anything, so I'm not sure but 0.0017 isn't that bad for out of round is it? Was your bike an oil burner? I eventually hope to do mine as well, it's not really using oil but I rode a 685 of a friends and I liked the extra "kick" :)

Cheers,
Stew

I don't know either, wonder what a new or non oil burner measures?

Tom did the rings look like they were making contact all the way around? The rings will expand some as they go up and down the cylinder, 1 thousandth seems reasonable. The rings will rotate there's no post in the grooves to stop them like on a 2 stroke.

I remember you saying that you burned a lot of oil on your Death Valley trip. Was the head gunked up? Top of the piston? Did you notice a blue cloud following you?

Another question, do you have the thermobob installed?
 

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Discussion Starter #4
Spec and 650Stew -

I thought the cylinder was in pretty good shape. A couple of thousands isn't that much for out of round, and less than a thousandth of taper is nil.

The rings were shiny all around, so contact was there.

The head and piston were good and gunked up. I have pictures that I will try to post up (I need to set up another flickr account; too cheap to spring for a pro account).

I've been told that she smokes a bit by folks following me... Stew: yup, she's a real oil burner.

T-Bob was installed some time ago. Don't remember the exact mileage.

T
 

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Ah, so it was a burner... Perhaps I've just been lucky with mine so far. I only have 9000km's on mine though, so perhaps consumption will go up yet. I had read accounts of the ring grooves all being lined up, but your ring end gaps being staggered kind of discounts that one. Sure would be nice to find out the "silver bullet" that causes all that oil to blow through. I'll be following this thread with great interest, I think the 685 is a great upgrade, the power difference is definitely noticeable, especially climbing from a stocker onto a 685. Thank you for taking us along with your upgrade :D.

Cheers,
Stew
 

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Discussion Starter #6 (Edited)
The bore:



The gunk:

 

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Thanks for taking us along on this adventure, Tom. So many things can contribute to oil consumption, and a combination of a couple of them would be impossible to pin point I would think. Valve seals are bigger culprits on today's engines more often than rings. I have no evidence that this is an issue with the KLR. Break in procedures, operating temperatures, load weight, wind, operator riding habits, on and on and on...... Ring flutter would be hard to confirm outside of a laboratory atmosphere, and even then to be able to replicate the oil usage amount with consistency would be difficult.....

And if the cylinder is the issue [distortion being a top speculation concerning oil consumption], how is the cylinder improved by reaming it out, creating an even thinner cylinder wall.....although it seems to work.

"Head work" is a black art in my book. Larger valves serve a purpose. As far as the porting, how much is taken off where is a mystery to me. I can't pin anyone down to specifics as to where they machine, and how they determine how much to machine off. Polishing makes sense to me. I have no proof it enhances performance, but it makes sense that smooth surfaces would enhance flow. Hopefully I will learn as I follow along here. I have every confidence that this project will be done right, and all outcomes will be reported objectively. My bike, the "'Little Valdez", is pushing out about one and a half gallons of oil per 1200 miles. I need a solution and will be watching carefully.
 

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So, next trip we're trading bikes, right? :)

Soon, we ride. (congrats on the 685 brother...looking forward to hearing about the change)
 

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Discussion Starter #9
vatrader-

I'm doing the head work/valves because it's off and because I can - no real reason other than that.

Pictures were taken of the intake and exhaust ports; perhaps we'll be able to see the difference. My understanding is that there really isn't much room for porting on the KLR head, so it will probably be a bit of clean up of the casting more than anything else.

And on the cause of the oil consumption, I gotta tell ya I was hoping to find a distorted cylinder. The only thing I can figure is that, with the cylinder in that condition and with only 20K on the engine, the oil has to be going past the rings.

I'm with ya on the boring out thing - it's an 80-over bore! Yikes!

Sure glad the KLR is not rare and not expensive....

Tom
 

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Discussion Starter #10
So, next trip we're trading bikes, right? :)

Soon, we ride. (congrats on the 685 brother...looking forward to hearing about the change)
You take the KLR, I'll take the 450....

T
 

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Thanks for taking us along on this adventure, Tom. So many things can contribute to oil consumption, and a combination of a couple of them would be impossible to pin point I would think. Valve seals are bigger culprits on today's engines more often than rings. I have no evidence that this is an issue with the KLR. Break in procedures, operating temperatures, load weight, wind, operator riding habits, on and on and on...... Ring flutter would be hard to confirm outside of a laboratory atmosphere, and even then to be able to replicate the oil usage amount with consistency would be difficult.....

And if the cylinder is the issue [distortion being a top speculation concerning oil consumption], how is the cylinder improved by reaming it out, creating an even thinner cylinder wall.....although it seems to work.

"Head work" is a black art in my book. Larger valves serve a purpose. As far as the porting, how much is taken off where is a mystery to me. I can't pin anyone down to specifics as to where they machine, and how they determine how much to machine off. Polishing makes sense to me. I have no proof it enhances performance, but it makes sense that smooth surfaces would enhance flow. Hopefully I will learn as I follow along here. I have every confidence that this project will be done right, and all outcomes will be reported objectively. My bike, the "'Little Valdez", is pushing out about one and a half gallons of oil per 1200 miles. I need a solution and will be watching carefully.

I read somewhere that some thought the OEM rings lacked tension on the Gen 2s. There was a thread about replacement higher tension rings but if I remember right that didn't solve the consumption.

I think that the 685 kit works because you start out with a fresh hone, good piston and rings. The theory that the cooling system is shocking the liner doesn't make sense to me as a thinner liner would aggravate that. The Thermobob is a good mechanical practice but dirt bikes don't have a bypass cooling system and they don't warp the liner.

Vatrader your bike must have a broken ring or the valves seals/seats are bad. I'm surprised it doesn't foul a plug!
 

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Discussion Starter #12
Spec -

I can't help but wonder why there isn't a good, well known, readily available ring fix for this. It would seem so simple to swap a set of rings in and do a quick hone. You could fix it in an afternoon.

Could it be that the new piston is as big a culprit as the rings, or that the combination of the two is the problem?

In another thread I said that you might be able to fix this with a pre-'08 piston and ring set, but the problem there is that the cost would be approaching the 685 kit.

T
 

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Spec -

I can't help but wonder why there isn't a good, well known, readily available ring fix for this. It would seem so simple to swap a set of rings in and do a quick hone. You could fix it in an afternoon.

Could it be that the new piston is as big a culprit as the rings, or that the combination of the two is the problem?

In another thread I said that you might be able to fix this with a pre-'08 piston and ring set, but the problem there is that the cost would be approaching the 685 kit.

T


Here's the thread about the replacement rings:

http://www.klr650.net/forums/showthread.php?t=40738

There's too many variables (for me) to make an informed opinion from a forum! Who knows how the OP put the thing together or if the hone was good or whatever. I'm with you though seems like good rings and a hone ought to fix it.

There's so many screwy theories about this, the PCV mod being my favorite. I believe that Kawasaki was aware shortly after production started that there was a problem and knows how to fix it, if someone can just find the emails!
 

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Discussion Starter #15
Oh, poop.

I was trying to read the thread and find the conclusion when all of a sudden (there I was, just reading along, minding my own damn bidness) the server became Extremely Busy and I could read no more.

On a Monday morning at 9:50 Pacific....

Tom
 

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Spec -

I can't help but wonder why there isn't a good, well known, readily available ring fix for this. It would seem so simple to swap a set of rings in and do a quick hone. You could fix it in an afternoon.

Could it be that the new piston is as big a culprit as the rings, or that the combination of the two is the problem?

In another thread I said that you might be able to fix this with a pre-'08 piston and ring set, but the problem there is that the cost would be approaching the 685 kit.

T
Little talked about is the fact that the "685 Kit" was on the market and aimed at high oil consumption KLR 650's loooong before the Gen II bikes hit the streets. Using the components from Ma Kaw for the Gen I top end may not improve your lot much.

Last September, four KLR 650's headed out of Front Royal, VA for Spruce Knob, WV. And back to Front Royal. 268 miles round trip, about a third of that low speed mountain back roads [read, goat trail]. On returning to Front Royal, then eating dinner, we topped the oil off in the bikes. Exactly one gallon. Two '04 models, an '07 and my '01. 1078 miles that day between the four bikes. All left my house with oil to the top of the sight glass. They all run great, do not indicate a lack of compression, and do not foul out plugs. My plug has over 26,000 miles on it. It was pulled and gapped @ 20,000 miles, and other than a wore electrode, looks fine. I do the majority of the work on two of the other bikes, both have under 12K miles, and both have the factory spark plug in them. I put a stock header and exhaust on one of the '04's last summer, and the SuperTrapp system that was on it showed no trace of wet oil, or even heavy carbon build up. That bike will use a quart in 300 miles easy.

As with some other issues with KLR's and their owners, if your Gen I or Gen II bike uses oil, they all use oil.......if your's doesn't use oil, .....none of them do. Sorting the wheat from the chafe is a project in itself.
 

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Discussion Starter #17
vatrader -

Interesting perspective, that. Kinda puts the kebosh on my idea about a pre-'08 piston, don't it?

I've always been suspicious about "my bike doesn't use a drop of oil between changes", as I figure a quart in a thousand for a four-banger is realistic.

It would be nice to have the bike only use oil down to the 'min' mark between changes.

T
 

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vatrader -

Interesting perspective, that. Kinda puts the kebosh on my idea about a pre-'08 piston, don't it?

I've always been suspicious about "my bike doesn't use a drop of oil between changes", as I figure a quart in a thousand for a four-banger is realistic.

It would be nice to have the bike only use oil down to the 'min' mark between changes.

T
As long as we are lingering on that topic, if the design of the Gen I top end was producing such favorable results, why was it changed for the Gen II bike? I mean, take a look at what all remained unchanged with the rest of the engine. Why the change of piston and rings if it was working so well? Why not the cylinder? The bottom end? Where's that Myth Buster girl when I want her?
 

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Discussion Starter #19 (Edited)
I thought that was where the sixth gear came from... you know, the one in the owner's manual...

Must admit, I thought oil usage on the Gen1s was not a prevalent issue so I always wondered why they changed the piston on the Gen2s.

T
 

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Discussion Starter #20
Oh, poop.

I was trying to read the thread and find the conclusion when all of a sudden (there I was, just reading along, minding my own damn bidness) the server became Extremely Busy and I could read no more.

On a Monday morning at 9:50 Pacific....

Tom
OK, the main poster in that thread stopped posting to that thread two years ago, apparently without resolution to his ring research. He had done a lot of good work, but it didn't seem that he got to the place where he was happy.

Quite a knowledgeable guy.

The thread picked back up a year and a half later as a 685 thread.

T
 
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