Bad clattering from shift fork area

[dweomer21]

Hi all, I am posting this to see if anyone has any pointers. Sorry this will be a little vague, since I haven't gotten a chance to get into my bike to check out the exact problem, but I am hoping the signs & symptoms will point to something that will get me started in the right direction in fixing it.
I have 1980 xs1100 special (xs1100 sg)
I was riding to work this morning on the highway, going about 60mph, when I noticed that the slight clattering I have always assumed was the valves needing adjustment, started getting progressively louder, and I started losing power. I pulled over jst as the sound got _really_ loud, as if there was loose metal or something being tossed around inside my engine, and then the bike stalled. After waiting about ten minutes, I started the bike again to see what it sounded like, and I hear a very loud clattering sound in what sounds like the left side of the engine (specifically, in the area where the shifting fork is). Now, I used to have a 79 xs11 special, and it had the shift fork break on it, but I was then stuck in 2nd gear. In this case, I am not stuck in any gear - I can still shift into and out of all gears, so I am not sure it is related to the shift fork. In any case, though there is plenty of oil in it, when I removed the oil cap, smoke/steam/fumes came out of the hole, making it seem like perhaps the oil wasn't getting spread through engine as it should, and the engine heat was breaking down the oil. I admittedley haven't changed the oil since I bought it two weeks ago, and it had been sitting for a year before that. Murphy's law of course dictates that because of the fact that I was waiting till payday three days from now to give her fluid chages, etc, it would of course happen before then
Anyway, I know that "clattering in the engine" is a very vague description, and I will probably have to break it open to find the exact cause, I am hoping there is an immediate obvious answer someone could point me to...
Regardless, I will reply to this post as I work on it for anyone who might be curious what happened.

Scott B

[John]

Each of the transmission shafts has a ball bearing at each end. The main shaft also has ball bearings on the ends. A worst case scenerio would be the oil pump gear has some broken teeth, or something has jammed it, then fell away allowing you to restart. One way to check for oil flow is to remove the bolt that is above and a little ahead of the starter on the left side of the engine. It is in line with the oil pressure switch, and it plugs an oil galley. If you can find a gauge with metric threads that will fit in place of the bolt, that will tell you what your oil pressure is , or if you even have any oil pressure. Also the middle gear is right above the shift lever. That is another potential source of the problem. Does it lock up when it is rolling? Hard to push? Good luck with it.

[TopCatGr58]

Hey John and Scott,

Several parts of his description sound much worse, like connecting rods getting loose!!! Also the fumes part, like his oil might have gotten contaminated with fuel. He bought the bike 2 weeks ago, had been sitting for at least a year, the dreaded carb float valves not sealing, fuel into the oil (has plenty of oil!?) causing it to break down and therefor not lubricate properly, overheat, spin bearings and such!!!???

Take a metal stick/rod, dip it into the oil thru the filler cap, remove and try to light with match/lighter, IF lights, then gas is in oil!! And with the ever increasing sound of this "CLATTER", could have spun bearing, connecting rods getting ready to go!? Good luck!
T.C.

[dweomer21]

Thanks John, I will check those things on friday when I get my bike into the basement and start working on it. Oh, and TopCatGr58 just replied while I was writing this - thanks for you rinfo too (though it is somewhat depressing!).
Here's a followup to my previous (somewhat premature) description of the problem. The really loud clattering noise sounds very similar to the cam knocking problems that older viragos suffer from (can't remember the exact TSB #). Before, I thought the knocking/clattering sound was coming from the shift fork area, but now I find that it is just coming from the bottom half of the engine (or thereabouts - not sure if in crankcase or engine though). There are no problems whatsoever with shifting or the like...i.e. no dragging, not hard to push, etc.
As for gas in the oil - just checked and oil is ok in that regard (thank gads). The smoke/fumes/steam that I mentioned in my first post may have just been superheated oil fumes from poor oil flow (as John mentioned), but I am not certain.
In summary (until friday when I have more info) the clattering sound is like a really loud version of camshaft wearing prematurely. I disconnected each spark plug for a few seconds to see if it was cylinder specific, but it is not - noise happens regardless.
Ok, thanks again for everyone's time - it is much appreciated!
scott

[TopCatGr58]

Hey there again Scott,

Well, with the engine possibly overheating, the rings and pistons would/could have gotten tighter and increased friction, causing you to loose power and eventually stalling. The slapping sound could be your HI-VO chain getting a bit loose and slapping against the case!? These oil pumps are pretty tough. And the filter chamber bolt has a bypass ball so if the filter got too clogged, it would bypass it to keep oil flowing thru the engine! Have you done the cam chain tensioner adjustment, could even be that!? Does your oil pressure light come on when you turn the key before starting the bike, and does it go out after starting!?

Not much you can do about the Hi-Vo, been told they aren't available from Yamaha anymore, and you have to split the cases to replace it anyways! Hope you find that you DO have oil pressure! Use a good thick 20-50 range NON synthetic. Good Luck!!
T.C.

[dweomer21]

UPDATE

Well, found the problem. The plane bearing for connecting rod #2 went out, and the result is a whole lot of aluminum debris in crankcase, as well as damaged con rod and crank! Doh!!
I think the damage to the crank is too much for a machinist to fix, but luckily, I just purchased a crankshaft assembly on ebay for $100, and will be swapping it out as soon as it arrives.
This has been quite an adventure! Thanks for all the hints and ideas from people - they were much appreciated. Though the actual problem is perhaps almost as bad as it could be, I am actually excited about the project; if I get this bike back up and running, she's going to be a real special girl, so to speak

-scott

[Geezer]

Where are you located? Maybe one of the list members can help you with the reassembly?

Geezer

[dweomer21]

I'm in Seattle (Ballard/Greenwood area specifically). Sure, if anyone wants to volunteer help, I certainly wouldn't refuse! If I do have to do it alone though, I am pretty sure I can manage it. Though this is a first time engine disassembly, I am quite mechanically inclined - though the need for some parts to be to the 1/1000th of an inch (or better?) is making me somewhat nervous. My brother has machining skill, but his tools and equipment are all back in New York. My calipers only go to 1/1000th, and they aren't even dial calipers, so I doubt I would even get that precise.

Anyway, thanks all!

[strom]

OK... a manual helps, but there isnt much need for such precision.

Parts are just made to fit together, so just don't overtighten something and strip the threads.

But... the bad news.....

You MUST dissasemble EVERYTHING and FLUSH it with large quantities of whatever... first engine degreaser, then high pressure water, dry, spray with WD40 and put in a box.
Including cases and especially oil passages.
I'm afraid that means dissasembling the valves, and you would need special tools to do it right. There are oil passages under there and you must get every metal shaving out.
I would flush the oil cooler (if any) with diesel, then oil.
Change the oil filter and oil pump.

1st. there is a reason that bearing went, most probbably because of the oil pump.

2nd. Metal shavings scratched it too much anyway.

Another problem will be clutch dis/assembly, use apropriate tool, since those stubs break easily... and don't brake the star plate.

Then there is primary shaft... the one with a big springy thingie on it. But it only takes some cursing.

Change the oil after you put everything back together after 20 miles, or at least run it through a fine filter.... pantyhose work best. Change at 200 miles again. You won't believe how many shavings show up.

Cranks cannot be repaired, since the engine revs too high.

I had the same problem with kawasaki. Replaced crank, all rods and bearings, oil pump,.... and it's a nasty job worth doing well.

Do all the cleaning yourself, since it's the only way you're gonna be sure it's done right.

Replace the crank oil seals while you're at it. And the camchain, unless it was changed recently. It's a while-you're-at-it job.

Sorry to bring the bad news, but it's not as grim as it looks. At least you'll know what this thing looks like from the inside. They don't make em like this anymore, trust me

LP

PS: Check or have checked all the crank and conrod bearings. They should still be avaliable from your friendly yamaha dealer.

[Geezer]

Originally posted by dweomer21
I'm in Seattle (Ballard/Greenwood area specifically). Sure, if anyone wants to volunteer help, I certainly wouldn't refuse! If I do have to do it alone though, I am pretty sure I can manage it. Though this is a first time engine disassembly, I am quite mechanically inclined - though the need for some parts to be to the 1/1000th of an inch (or better?) is making me somewhat nervous. My brother has machining skill, but his tools and equipment are all back in New York. My calipers only go to 1/1000th, and they aren't even dial calipers, so I doubt I would even get that precise.

Anyway, thanks all!

I'm a little south of Portland and about 4 hours away so maybe one of our more northern members can lend you a hand with it.

Geezer