need help diagnosing bottom end noise

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snorkelfork
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need help diagnosing bottom end noise

Post by snorkelfork »

Recently picked up a 74' T500. It needs to be tuned but the top end sounds tight and even out of tune is responsive.

there is a sound that i hear from what seems to be both side of the lower end that sounds to me like an empty pepper grinder. when the clutch lever is engaged while in neutral the sound goes away but other wise it can be heard all the time if you are looking for it.

it was suggested to me that it sounds like a bad bearing in the lower end, I'd like to hear some opinions before I consider digging in.

all of my 2 stroke experience is with RD's which obviously are a different sort of animal all together.

thanks...jeff
titan performance
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Re: need help diagnosing bottom end noise

Post by titan performance »

The clutches are often noisy on these old girls........
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snorkelfork
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Re: need help diagnosing bottom end noise

Post by snorkelfork »

is it typical that you can't edit your post on this forum?

i went back to verify my post and realized that it in fact only makes the noise while sitting in neutral, and actuating the clutch lever stops it while in neutral and in gear. while riding there's too much racket for me to hear whether it's there or not.
Craig380
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Re: need help diagnosing bottom end noise

Post by Craig380 »

+1 to Titan's post, pulling in the clutch lever at idle will stop the clutch rattle (you do get some on 2-stroke Suzis, especially older ones) and of course it stops the gearbox shafts turning too.

If you haven't done this already, try a change of gearbox oil and see if that helps quieten things down.

One thing to note on the 500 twins, when the clutch lever is pulled in, the oil pump is NOT turning, so don't sit at stoplights for long periods in gear, just knock it into neutral :D
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Digger
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Re: need help diagnosing bottom end noise

Post by Digger »

Craig, that is superb advice, thanks. :up:

A quick ride on a Ducati will cure you of that worry, snorkelchap :up:

(... and I'm still wondering why an empty pepper grinder would make a noise :lol: :lol: )
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titan performance
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Re: need help diagnosing bottom end noise

Post by titan performance »

I knew what you meant Snorkel. I have 2 T500s that have made that noise for over 30 years.
When the bike sits at idle it rattles...pull in the lever, and it stops. I believe the clutch itself is the source of the noise. A number of bikes suffer a noisy clutch, my CBXz 1000/6 was the worlds worst.....but the clutches have always functioned fine despite the noise.

PS..there is an edit option bottom right of your post. If it's not there, you haven't logged in.
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Re: need help diagnosing bottom end noise

Post by jabcb »

See Service Bulletin # General-15 if you decide to fix the clutch rattle noise:
http://www.ozebook.com/compendium/techb ... 010-18.pdf
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GT500Andy
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Re: need help diagnosing bottom end noise

Post by GT500Andy »

I think that all Suzuki 's do it I've also got a v strom from 2007 it rattles, by the dealer one day a new v strom came out of the showroom and when they started it up to my astonishment it rattled as well when I pulled the clutch in it stopped.

Andy
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Re: need help diagnosing bottom end noise

Post by Barry S. »

It's not only Suzuki's, about all of them do it.
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Re: need help diagnosing bottom end noise

Post by Fritz500 »

I fixed my clutch rattle in about an hour. 40 minutes of which was going to the tool shop to buy the right sized clutch nut socket.

I took the clutch apart and removed the plain bush on which it runs. Shorten the bush by rubbing it on some 800 grit paper. Slow and gentle. A few test fits and bingo the end float on the clutch is gone. I did it at about 10,000km and didn't have to do it again. I did on both my T500s with no issues at all.


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jabcb
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Re: need help diagnosing bottom end noise

Post by jabcb »

An easy fix when you followed the old Suzuki technical bulletin.

Seems they are really worth check out when you have a problem:
http://www.ozebook.com/compendium/techbuls/
Certainly makes sense -- back in the '70s they were written for Suzuki mechanics.
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Re: need help diagnosing bottom end noise

Post by rbond »

My GT500 rattled alot too. Turned out the main culprit was a loose pinion nut on the crankshaft. Clutch basket has no excessive play and it's nut was tight. Once I tightened the crank nut,it was much quieter and actually idled smoother. The extra flywheel effect of the clutch basket helped on that. A little rattle at idle is normal for these bikes, if it gets really loud, you better pull off the clutch cover and check it.
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