middle drive noise

[nightpilot]

While running my xj11 with less than 30K on it on the center stand to flush out the old middle drive with clean oil I found it to rattle and make some kind of loud banging noises when at idle with first gear engaged that seemed to go away when speeded up a little. It is intermittent but does not sound good. Anyone ever heard anything like that, is it normal?

[petejw]

Hi Nightpilot,
Im not sure how much experience you have but if i read it correctly
youre running the engine in gear spinning the rear wheel while draining the middle drive gear oil?
Never run anything while draining oil, gravity is efficient enough to drain it from the case, this can cause the middle drive to sieze otherwise, depending on how long you ran it for. now in saying all that the xs is clunky at the best of times changing into 1st, which makes it worse when its on the center stand and idling.

[nightpilot]

middle gear noise

Maybe I should not have written the thread so early in the morning, was trying to be brief. No, the middle oil was filthy so I ran a couple of changes through it but did not run it when dry. I was hoping the crew with greater experience with this drive would be able to tell me if noise, esp at idle speed was normal. I am sure, as with everything, there is a little noise, but the big question is what is normal. when i tested it for about a mile before starting to clean out the oil the middle gear had a little whine. But, other than the accumulation of black gunk metal on the magnetic plug, I have not seen any new shiny metal in the oil when drained. We always look for shiny metal in airplane filters so was looking for that here.

Thanks for the thoughts.

[randy]

What you're hearing is the cumulative lash in the primary chain + transmission + middle drive + final drive and it's normal for these bikes to do that with no load on the drivetrain. Try it in second gear and see how it quites down. I liken it to the chug-chug sound of a locomotive! The sound can be worsened by a low idle, or a poor carb synch.

[oldnortonrider]

I can't believe that Yamaha didn't put something in the rider's manual "not to run with rear wheel off the ground". And, in fact, it should have been in the maintenance manual(s). ..................long story.................I nearly went into a panic, about 15 years ago, first time, and last time, I tried to run with rear wheel off ground. Probably, a good deal of the problem of the dogs being messed up on different gears in the transmission, is caused by this. I'm also amazed that there have not been many more "caveats" put on this forum, over the years~~"not to do this".

[nightpilot]

Good point oldnorton I became real concerned when I heard the noise, btw interestng idea on the kaw tank. I have been

Randy that makes total sense about the cumulative lash re how it acted and sounded. It happened at dead slow idle and when i sped it up even in first the bad noises went totally away, did not put it in second except once and at idle.

Generally glad to hear that most dont think the noise is a problem because the bike is being set up to go long distances solo in the west and locking the rear wheel up at 80 while 100 miles from nowhere does not sound like my kind of fun.

[fredintoon]

I can't believe that Yamaha didn't put something in the rider's manual "not to run with rear wheel off the ground". And, in fact, it should have been in the maintenance manual(s). ..................long story.................I nearly went into a panic, about 15 years ago, first time, and last time, I tried to run with rear wheel off ground. Probably, a good deal of the problem of the dogs being messed up on different gears in the transmission, is caused by this. I'm also amazed that there have not been many more "caveats" put on this forum, over the years~~"not to do this".

Hi JCR,
I can't get my head into your thoughts on this. Certainly just because I can't understand why running with the rear wheel off the ground will wreck the tranny don't mean it ain't so.
Keeping the rear brake pedal down a bit should simulate a drive condition.

[randy]

I've found when running it with the wheel off the ground there is definitley something missing, the bike doesnt launch nearly as fast as with the wheel on the ground.

[fredintoon]

I've found when running it with the wheel off the ground there is definitely something missing, the bike doesn't launch nearly as fast as with the wheel on the ground.

Hi Randy,
that's because you ain't doing it right.
Climb aboard, take her up to 7,000 rpm in 2nd gear then rock the bike back on the centrestand until the rear wheel hits the blacktop.
Then hang on.

[randy]

Oh, OK, I'll try that. I'll call you from the hosp.!