Died mid-ride, runs now; seeking opinions

[clofan]

Hey guys, wanted to post a quick experience and get some opinions on what happened / where I need to go from here.

I was riding at 65 in 5th (very close to top speed, most likely WOT) when the bike started lurching and surging, almost like fuel starvation (still had 1/4 of a tank). I pulled the clutch and it sputtered for a bit and died. Could not get it to restart at all! I checked the oil level, and it was just a couple MM below the low limit . I left it, then went back to it ~4 hours later, added some oil to get it in spec, and attempted start-- no go. It would just turn over endlessly, never catching at all.

So, I trailerd it home. Let it sit for a few days while I was camping, then started work on it. First of all, with a tiny bit of coaxing and choke, it started. Ran rough for a couple seconds, but once it warmed it was idling and riding OK. Took it around the block a couple times, no issues at all that I could feel. I rode it on a long straight road and at WOT in 5th, it started sputtering and lurch/surging again. I pulled clutch and kept it alive with a little throttle while I slowed down, and it never died. Idled fine after that. I ran this test again, and it seemed to start acting funny around 30-45 seconds at top speed/gear. Of note, in 3rd/4th WOT, I didn't seem to have any problems; however, because of the high RPMs in those gears I didn't run it like that for as long as I did in 5th.

I noticed a small oil leak, but couldn't exactly tell where it was coming from. No oil on the ground, only on the fins and lower engine. I cleaned up the cases a bit, so hopefully I'll be able to determine the leak location soon. I may even have multiple leaks, as there were a couple areas that seemed suspect; namely the head gasket, right side case, and possibly around the head bolt near the spark plug.

I didn't ride it to work this morning for fear that the issue would rear it's ugly head again. It's been 974 miles since the last oil change, so I guess I might do that. I'm also feeling like I'm going to need to replace the clutch plates soon, as it slips occasionally. Finally, I'll take a look at the airbox to make sure it's OK, and maybe run some seafoam through the carb.

Any other thoughts or suggestions? Thanks in advance!

Edit: Bike has very near 10,000 miles on it. It's had some other issues too involving the flywheel and backed out bolts, but I think that's unrelated here.

[Fawlty]

No need to change the oil yet. With regard to the clutch slip, I assume that you used motorcycle specific oil, if not then you do need to change it. I am sure others will be along soon with expert advice.

[clofan]

Oh yeah, JASO-MA compliant always. Still using dino oil, no synthetics because I'm cheap. I did put some seafoam in the oil one time before a change-- some people claim it's bad for the clutch, others say it's fine. Either way, that was 2 oil changes ago so it really shouldn't be affecting it now.

[spldart]

Sounds like contaminants in your fuel tank to me.
But that is a very rough armchair guess.

A compression test is also in order

The rubber seals in the valve lash adjust covers can get to hard to properly seal. This will lead to
oil down the front and sides of the motor due to wind blowing it around.
As a temp fix I did a bead of silicone gasket sealer around these little covers and all of a sudden I
don't have a slow leak.

[clofan]

You know, I hadn't thought of contaminants in the tank / line. You may be right; I suppose I should get a fuel filter inline since the bike is getting up there in years.

Compression... Yeah I guess I ought to do that. Never done it on this bike, because it hasn't ever had any problems in that regard.

You could also be right about the valve cover gasket... Some of the oil was so high up on the fins that that seems the most likely culprit.

[clofan]

Just a quick update on this thread. I cleaned out the fuel tank, took off my petcock and found that the filter tube for "ON" was missing. Jiggled the tank and sure enough, it was in there somewhere. I was able to fish it out with a wire hanger and reattach with some E6000. Because of the lack of the filter tube, I assumed the issue was contaminants in the fuel stopping flow. On the bright side, my Reserve settings works as intended!

I also added an inline filter. Check the attachment, it's that type.

It happened again this morning. Running at ~60MPH, wide open throttle in 5th. Started stuttering, so I pulled clutch and it died. I waited a little bit (maybe 1 minute), then it started back up. The idle seemed 'weaker' then normal. It stayed on, so I continued on my way to work. It died again after about 2 miles, this time at ~80% throttle at 55mph. I waited again, started it back up, and continued on the last two miles of my commute without issue. Mind, I was babying it and trying not to go anywhere near full throttle.

At this point I'm thinking fuel flow. Like maybe it's trying to use more fuel than is being delivered? Is that a possibility? I never did do the compression test, I need to go rent the tester from AutoZone.

[clofan]

Hmm, I'm a dummy. That fuel filter leaks, oh, it's supposed to be mounted straight up and down and mine is tilted. I'm fairly sure the float bowl wasn't filling quickly enough for WOT due to this filter, causing a starvation that rectifies itself after a few seconds.

[blaine]

Yep.. Straight up & down......Sounds like your problem.

[chandlerbingfl]

I'd agree to starvation....

chandlerbingfl

Originally Posted by blaine

Yep.. Straight up & down......Sounds like your problem.

[raul10141964]

check the valves if the gape is to small the engine lost compression when is hat