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Transmission "knocking" noise?

4.8K views 7 replies 5 participants last post by  TeeRiver  
#1 ·
Hello everyone, I have a 1999 SV650 with 13,5xx miles on it. The bike ran fine when I bought it about a month ago. The PO road it about 45 minutes to meet me, and my brother road it and had no problems.

About a week ago it started to make a "knocking" noise when shifting. I go from neutral to first and start to accelerate, the bike will make a knocking noise that sounds like its coming from the left side of the bike. Its about 3-6 knocks and then its gone, it does not get louder or faster with an increase in rpms. The bike does this through first, second, and third gear and is fine after that.

The bike also does not do this every ride. Today it started out fine, I road about 30 minutes on the highway and then about 5 minutes of back roads. Coming out of a stop sign the noise started again.

From a small search I did on this sight, it sounds like oil might help? Any other suggestions? I will try to answer any other questions you guys have
 
#3 ·
... Its about 3-6 knocks and then its gone, it does not get louder or faster with an increase in rpms. The bike does this through first, second, and third gear and is fine after that.
The chain is shot. Worn chains make the most noise at low speed and heavy load (acceleration), and is independent of engine RPM.

You can make sure by propping the back wheel off the ground and check slack at several places as you spin the wheel. If there is a big difference between the loose and tight sections, then it's time to go shopping. 15k is typical chain life. Congrats on your new bike. :)
 
#6 ·
When you push the chain up and down, it will have more or less slack in different parts as you rotate the wheel to different positions. This indicates that sections of your chain are longer than others, and the chain is tightening up. Also links that come off the sprocket and dont straighten out but ride around "kinked" are good indicators of a shot chain. Give it some lube and make sure the tension is in spec at the tightest point and it may last a little while. I know mine didnt :(
 
#7 ·
You measure chain slack at the botton of its run halfway the distance between the two sprocket centers. Basically the space left between the sidestand and the rear sprocket. If you have a rear stand, you can rotate the wheel and check to see if the chain slack varies greatly at different points along the chain. If not, you set the slack or tension at the tightest point along the chain run. The slack spec is 0.79-1.18". I mostly set the slack at 1" on my SV. Most will replace sprockets when replacing a worn chain, although there are those who will argue if the sprockets are in good condition, no need to replace. Others will argue that worn sprockets will prematurely wear a new chain. This is one of those no win arguements. I myself always replace sprockets with a new chain. One other point, if you adjust the slack within specs and you can pull the chain off the rear sprocket at the 3 o'clock position by more than 1/16", the chain is probably stretched beyond its spec.