[rc514789]

Whenever I'm sitting at a red light and go to take off there is a relatively loud knocking sound coming from the bike somewhere!!! I here it and it gets louder untill i get up to speed then I here it in second a lil. I can't figure out what it is. My bike is an 02 RC51 with almost 16,000 miles, could it be the valves? or the clutch? Please help

[rokitt51]

Could be the valves and the clutch too. But check the cheaper routes first. Check the chain and the sprockets, they could be causing the knocks that you hear. My RC was valve checked at over 16,000 and was all good, and i do alotta ridin.

[rc514789]

What do I need to check on them?

[Beattie_Yo]

a service manual will tell you everything you need to know do do the inspection yourself. i believe all you need is a a few metric tools and some feeler gauges to measure clearances with. most of the labour involves removing the bodywork and tanks to gain access to the front/rear cyl heads

a looser chain can also cause a bit of rattle which can cause a hiccup in 1st-2nd gear transitions. check tension of and lube chain as often as you can remember...2cents

[rc514789]

So I was ridin home from work tonight and was listening to it. It does it in every gear, and only while giving it throttle, and it comes from the front of the motor it sounds like. But its getting worse, when it first started happening it was just like one knock and now it just knocks and knocks as long as i'm on the throttle partially

[playwme]

Is your chain loose?

[breimers]

First lube your chain. I Don't suspect your chain because usually under load a chain will not make any noises unless the roller pins are completely wornout. Lubing with a thick chain lube will help eliminate the chain noise. I would suggest looking at your front sprocket. The loose or worn out chain may be chattering against a worn out sprocket.
I would not suggest you check the valves unless you are an experienced mechanic. they are a pain in the butt. The valves are not adjustable as most older Hondas. They have shims under push caps, will require you to remove the cams to replace the shims and the recheck the clearance. Good luck hope my advice helps.

[jzanutto]

if you or the previous owner have been doing burnouts, wheelies all the time, hard acceleration then the rear sprocket teeth may be letting that chain slip.

Look at the teeth on the rear sprocket. Go down to a bike shop and look at a new one on a rack if you need a good comparison for tooth height. My daughter's ZX7 was doing this until she finally told me about it and sure enough there were almost no teeth left on that rear sprocket

people tend to put aluminum rear sprockets on in an effort to save weight. they wear out fast