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Rattle around 3k rpm


swortsoul

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So my 2002 Lemans started to rattle, most pronounced around 3k rpm. I had just replaced the angle drive for the speedo, removed the speedo cable, cleaned it, lubed it, and re-installed it. I couldn't figure out how that would make a rattling sound. Well, it didn't. I hate when something else new happens when I'm test riding my last issue. For the record, the new angle drive fixed my speedo issue. Thanks for all who helped.

 

Now the rattle. It sounded like it was coming from the front of the bike. After a while, I noticed a missing bolt from the alternator cover. I'm assuming this is the source. I was just going to take it off, clean it up, and put it back. Is there anything I should worry about or know?

 

Next step is to check and tighten all external bolts.

 

Thanks

Tim

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Is rattle there stationary or just with bike moving?

 

It's there when it's stationary as well. I'm going to pick up a bolt to replace the missing one. Whenever I do something like thus, I normally take the whole thing off, clean/lube it, and reinstall. I just don't know what's behind the cover and if I need to worry about anything there. If it doesn't fix the rattle, I'll be back.

 

I find it odd that I only hear it from 3k - 5k or so.

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Is rattle there stationary or just with bike moving?

 

It's there when it's stationary as well. I'm going to pick up a bolt to replace the missing one. Whenever I do something like thus, I normally take the whole thing off, clean/lube it, and reinstall. I just don't know what's behind the cover and if I need to worry about anything there. If it doesn't fix the rattle, I'll be back.

 

I find it odd that I only hear it from 3k - 5k or so.

The alternator is behind the alternator cover. Nothing to worry about there. 3-5k must just be the range where it vibes the way the loose thing likes to be shaken. Frequencies and all. Er something. Is it really a rattle or more of a buzz? Regardless, it's ALWAYS a good idea with these bikes to go around checking hardware. Don't be afraid of locktite, either.

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Is rattle there stationary or just with bike moving?

 

It's there when it's stationary as well. I'm going to pick up a bolt to replace the missing one. Whenever I do something like thus, I normally take the whole thing off, clean/lube it, and reinstall. I just don't know what's behind the cover and if I need to worry about anything there. If it doesn't fix the rattle, I'll be back.

 

I find it odd that I only hear it from 3k - 5k or so.

The alternator is behind the alternator cover. Nothing to worry about there. 3-5k must just be the range where it vibes the way the loose thing likes to be shaken. Frequencies and all. Er something. Is it really a rattle or more of a buzz? Regardless, it's ALWAYS a good idea with these bikes to go around checking hardware. Don't be afraid of locktite, either.

 

I would say a metallic rattle. My first though was a screw being loose. Ya, I just haven't got to checking all the bolts yet. It's still new to me. That is tonight's project.

 

Well this is better than my KTM is treating me. It stalls every time I pull in the clutch. I'm being told to start the bike and let it idle for 15 minutes and something magic happens in the ECU. Give me a loose screw any day.

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Do you hear it when you blip the throttle? Trying to accellerate hard (WOT) in high gear?

 

If yes, could be pinging...

yeah, my '02 really pings under hard acceleration if i don't keep the revs higher than 4000 rpm. these are very high spirited engines & don't(in my opinion) like to be lugged.

i put 800 miles on the le Mans last weekend to the Chief Joseph BMW rally in John Day Oregon (site of the U.S. MG national last year).

my beemer wasn't charging at the last minute, unpacked it, loaded the V11 & left.

the V11 ran perfectly all weekend, got quite a bit of attention. out of about 500 bikes, there was only one other guzzi there, 1200 sport.

averaged 43.8 mpg.

and i didn't get that speeding ticket on the Washington side of the columbia river gorge (that i deserved) i thanked the patrolman, he likes the le Mans.

stef

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Do you hear it when you blip the throttle? Trying to accellerate hard (WOT) in high gear?

 

If yes, could be pinging...

 

I had this same problem recently, especially in top gear or when passing cars. It can be caused by exhaust leaks. I had a leak at the crossover by the right header, and crack on left side of crossover by the muffler. Once the crack was welded and whole system refitted properly the pinging went away. Anti-seize at all connection points seems to make a better union.

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I hope everyone is running PREMIUM fuel with as little alchohol content as possible......If not, don't cry about it. There are addatives in premium fuel that are not in regular fuel.

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  • 2 weeks later...

I should give an update for this. Definitely wasn't pinging. I use premium as well. Unfortunately, I can't find any decent fuel without 10%+ ethanol. I expect my tank to look like a shriveled raisin someday...

 

So I dropped by Moto International once to have Micha take a listen. Of course I don't hear the sound then, and neither did he. He said the valves could use adjusting. A couple weeks later, still no valve adjustment, it is getting louder. So last night I run back by MI, Micha listens, valves definitely need adjustment. So that's what it sounds like... Yes, I'm used to riding a Honda and KTM. Had one of those bikes sounded like that, I would've pulled over and shot the thing to put it out of it's misery. :)

 

Last night I put bike on stand, pull off one valve cover, put in high gear, pull both spark plugs, turn wheel to find TDC. I expect wheel to move freely since there should be no compressions with plugs pulled. It definitely doesn't spin freely. Takes a bit of effort every time a piston moves (valves open/close etc).

 

Is that normal? Probably is, but I've just had one friend tell me they had very little resistance (on their 4 cyl sewing machine...).

 

Man the stupid questions that come up with the first time doing this...

 

Thanks

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...Is that normal? ...

 

I'd say yes. It's better if you try this in 6th gear, and even then you need a firm grip. It comes from the valve springs. They're strong.

 

hubert

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...Is that normal? ...

 

I'd say yes. It's better if you try this in 6th gear, and even then you need a firm grip. It comes from the valve springs. They're strong.

 

hubert

 

 

H, you stole my thunder............. 6th gear will give you better leverage. In 1st you are making like 4 crankshaft revolutions to 1 wheel revolution. In 6th gear you are making 1 to 1. These # are not exact, so no one complain...........

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Finding TDC is the most difficult part of valve adjustment IMO. I've tried it both ways; turning the back wheel and by turning the alternator. Using the alternator is nice because you are right by the engine and can watch everything move. The tradeoff is, you have to remove more stuff to gain access to the alternator. On my bike I have to unbolt the oil cooler to get the alternator cover off. This, in turn, changes the position of my fairing mounts.

 

If you have a helper, the rear wheel technique is probably the way to go.

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