My original thread has dissapeared so this is a new thread.
My XB12 has had a metallic rattle between 3,000 and 4,000 rpm for some time. It only happens when the engine is under load ie moving under acceleration. It seems to be coming from either cylinder head, but really can't be sure.
Anyway checked the obivous, primary chain, plugs (pinking) and even changed the oil, thinking the hydraulic lifters where faulty.
Well Monday I rotated the engine and removed both rocker covers th check the Vv gear. No play in the rocker arms in position and no wear apparent when the lower rocker cover was removed from either cylinder. No uneven wear on the push rod balls or the tops of the Vv's. Only a slight bit of end float on the rocker arm pivots, but its equal for all four.
Any ideas welcome of anything else worth a check before I rebuild it.Thanks all Alan

Here it is

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"With square conduct, level steps, and upright intentions ..”

These were exactly the same symptoms when my XB9 failed with the worn crankshaft bearings. It ran comparably more silent while not under load, but e.g. accelerating out of a turn made the engine very noisy and it *seemed* to be limited to a rpm band.

Old thread: http://www.ukbeg.com/archive/modules.ph ... ic&t=31027

If the engine is still rotated, check radial play at the pinion shaft. I'm sure will tell you how much is acceptable.

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"It is often said that before you die your life passes before your eyes. It is in fact true. It's called living."
Terry Pratchett

My god, has anyone got any less expensive ideas lol. I'll check the play as I've got the primary cover off already, if i get any excessive play i'll bite the bullet and either get it done or do it myself. Think I'm destined back to a rice burner, need something more reliable( but it wont be as much fun though ). cheers Al

spare spark plugs under the seat rattling together and no it wasn't me that removed the barrels and pistons from an RD350 yamahe to cure it's rattle lol...but a mate did many years ago.

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2001 X1 2009 1125CR 2006 Uly X3 2010 Uly a fully Maz'd S1 and a 1991 RS1200 Westwind.

I get a rattle from behind the screen at 2250revs, think it's the horn. Fixed it with ear plugs

N.

Yep, tis the horn......they all do that sir

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Mithered ta death.
92 MB
96 S2T
98 S1W
00 M2
01 X1
03 P3
10 CR

i think this problem is not the horn rattling, I'm going to check the play in the lhs crank bearing. Then we'll see what gives. Anybody got any more ideas? Al

Is it still running ok?
When you ride it next, move your head around, back and forth, side to side or a combination of these. It dawned on me today that my old 'Bolt and Uly both make a noise like someone hitting a piston with a drumstick. A kind of tinckly noise.
I bet if you move your head around, this will go.

I use a roof helmet, what do you use?

Or are you running a stock exhaust? My exhaust (Exup) valve is rattling like a goodun until it's hot.

I use a KBC full face race replica, but the sound was even evident when we had the bike running in gear while on a paddock stand. You can hear the rattle ( just like something resonating) but can't locate it. If your nice and smooth with the power through the rev band then the noise just doesn't happen but if you rev hard its always there, cold warm or hot engine.

I seem to have a similar noise with my SX

It's like a very high-pitch rattle, most notably around 3k revs and best i can tell it's coming form the top of the cylinder(s) or under the airbox cover and 'maybe' more form the left.

It's really difficult to isolate, but seems consistent with the revs, doesn't go when you pull the clutch in (until the revs drop). It's not really very loud, but enough to be noticeable. Performance seems fine and doesn't seem to have gotten worse.

The bike's done 6k miles and I only ride it once or twice a week and have put it down to 'that's just the noise it makes'

Problem is, round here (Surrey) there's no one to take it to to have a listen - Warss will charge me £90 and hour

...but then again if it's likely to be doing damage I'd rather get it sorted

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"Because it's awesome" is always a good enough excuse

http://www.eugenereisch.com

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Mine doesnt cos I stuck a sanitary tow........er...sticky pad thing on the inside of the cover....works a treat !!!

I would if I could figure out which one(s) it was!

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"Because it's awesome" is always a good enough excuse

http://www.eugenereisch.com

I've checked the lhs pinnion drive for any play in the lhs crankshaft bearing and there is none, well none thats noticeable by me. So i'm going to rebuild the engine and primery drive and hope thats it either goes away or i can find something else wrong. I'll check the horn then but I'm sure its not that.
Any other things worth checking before i put the rocker covers back on?