600 sounds like a sewing machine?

[just4fun]

I’m pretty new to the whole street bike thing. I just bought a 94 600 Katana. It’s my first street bike and it starts, runs, idles, and looks great (very clean bike). But I do have some concerns after reading some of the online post here. My engine sound like a sewing machine, (to steal a term from another post). Is this how it should sound? I heard this could be caused by the CAM Chain. Is this something I need to get fixed ASAP? The bike does have 20K miles.

Any input would be helpful.

[chriskatana]

it is "normal"
here's a fx for it:

http://jht.gau.hu/~tracz/BikeFAQ/clatter.html

[irenekat]

its normal..i had the same sound from my '02 kat. try getting a full exhaust, it will eliminate the prob. otherwise, you'd have to live with it i guess

[The CyberPoet]

(A) It's common -- but it's not normal (the two should not be confused). The reason is the cam chain tensioner spring gets coated with gunk and doesn't push adequetly anymore against the rail which keeps the tension on the cam. Or the spring is simply weak with age and wear. Or the button the spring pushes on is worn away somewhat.

(B) It usually happens as a result of using poor oils (such as typical car oils or API SJ/SL rated oils) which can't take the load for the bike real well -- they get hot and under load, they form sludge, and that sludge can block up the spring (and/or permit the button to be worn away to a degree).

(C) Replacing the assembly or just the spring is usually the right answer.

(D) Note that there can be other reasons unrelated to the cam chain for such noises, such as the drive chain (inadequate lubrication, seized links, worn sprocket teeth, etc), valves out of adjustment, or cam slop.


PS - chriskatana, interesting read -- thanks for posting it!

Cheers
=-= The CyberPoet

[89katana750]

Why does it say not to remove the two allen bolts? I took mine out when I did it and put a new gasket. Is the tightness supposed to be bang on and even between the two bolts?

[SlipKid]

So what's a sewing machine sound like? Does it have chain slap?

[AkBigN]

are you hearing at idle or only when driving?

[benchfalco]

I had to replace the entire tensioner unit last season after attempting to torque down the alan bolts using a (as I later discovered) malfunctioning torque wrench....just as I was tightening I thought "gee this feel REALLY tight" then the whole unit shattered. Anyway, the old tensioner unit had about 50,000 Km on it, and when comparing it side by side to a brand new unit, the tensioner spring had compressed virtually ZERO by comparison,plus there were no signs of visible wear and each unit still had at least 6 notches of travel left for additional tension as the chain would continue to stretch over time. Also, my (cam) chain and sprokets showed no visible wear. I would guess that the only part that might ever need replacing would be the spring for a stronger one. BUT after reading that post about tightening the chain by pushing it in a notch or two to increase tighness to reduce chain rattle doesn't seem like a bad idea, since all the spring does is "automatically" compensate for cam chain stretch over time anyway; if you were to do it manually there would be no need for a new, stronger, spring. Of course, then you've got to manually tighten the cam chain as the rattle returns in the future....

At idle, my cam chain sounds like the drive chains on a CBR (lots of rattle); but at high speed my exhaust is too loud for me to tell if the rattle is still there or not.

Has anyone tightened their chain manually? AND, would this cause premature chain stretch, or significantly shorten chain life -- or did suzuki just install a weaker-than-they-should-have spring in the tensioner unit?

[xbubbax]

Has anyone tightened their chain manually? AND, would this cause premature chain stretch, or significantly shorten chain life -- or did suzuki just install a weaker-than-they-should-have spring in the tensioner unit?

no it comes nice and tight, but after hard riding of a brand new bike, or just wear and tear of an old bike. it just happens, and needs to be fixed. the chain wont as so stretch, but the constant spinning load on the chain tensioner, at high RPM's all the time, or just normal wear and tear, it still needs to be done.

its not so much a tightning the chain, its putting or tension force on the the chain tensioner