[Guest]

Bought an 04rc the other day. It has aftermarket chain (not sure what size and 15/41 sprockets, I think). Went for two long canyon days and noticed horrible lash and upon inspection a lot of chain slack.
I adjusted the slack out and while I still had it on the rear stand, started it up, clicked into 2nd and slowly feathered the clutch to get the rear spinning and view chain movement. What I got was a nasty clacking sound that seemed to occur only 1 time per full revolution of the chain. It sounded like metal on metal, but a clack not a grind.
Had a buddy with me and inspected everything, but couldnt see where it was hitting (if it was). Got on the bike on the stands and felt the knock coming more from the front.
Inspection of the front sprocket showed nothing irregular.
Took it out on the street and it was fine, just seemed to do it once or twice at very low rpms (1500-2000) during clutch engagment.

Sorry for the long winded post, just a strange issue I wanted to fully explain.

 

[Guest]

Re: Nasty knock of the chain... help (jbowers24)

Chain may be to tight, according to the manual play should be at 1" to 1" 3/8" if I am reading correctly however, the 1" 3/8" seems that it would be a little sloppy, some say should check slack with you sitting on bike, I say check it at different intervals as you rotate the rear tire some spots will be a little tighter wouldn't let it get over an inch though.

 

[Guest]

Re: Nasty knock of the chain... help (RC Cola)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RC Cola »</TD></TR><TR><TD CLASS="quote">Chain may be to tight, according to the manual should be an 1" to 1" 3/8" if I am reading correctly however, the 1" 3/8" seems that it would be a little sloppy, some say should check slack with you sitting on bike, I say check it at different intervals as you rotate the rear tire some spots will be a little tighter wouldn't let it get over an inch though.</TD></TR></TABLE>
Once we got the problem we adjusted it out some to see if that helped, to no avail. It did it, loose or tight, with or without me on it. Just has me wondering if its normal or something..

 

[Guest]

Re: Nasty knock of the chain... help (jbowers24)

I know this may sound funny but is it clean and lubed up? is it an "o" ring chain? just checking the obvious.

 

[Guest]

Re: Nasty knock of the chain... help (RC Cola)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RC Cola »</TD></TR><TR><TD CLASS="quote">I know this may sound funny but is it clean and lubed up? is it an "o" ring chain? just checking the obvious.</TD></TR></TABLE>
yeah, I did that on the off chance it could be the culprit, if only it were that easy.

edit.. yes o-ring.

 

[Guest]

Re: Nasty knock of the chain... help (jbowers24)

If you don't have a load on the wheel (running while on stands) you should/will experience alot of chain slap and back lash. Be sure you have the recommended slack in the chain ( if you not sure how to check that it should be in the manual), make sure the chain is still flexible between every link, then take it for a ride and see how it is.

 

[Guest]

Re: Nasty knock of the chain... help (RC51ing)

The chain may have a tight spot that is causing your "knock". Put the bike on the rear stand and give your wheel about 1/8th of a turn at a time and check the chains' tightness. It needs to be uniform all the way around. If it does have a tight spot, replace your chain.

 

[Guest]

Re: Nasty knock of the chain... help (taylspin)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by taylspin »</TD></TR><TR><TD CLASS="quote">The chain may have a tight spot that is causing your "knock". Put the bike on the rear stand and give your wheel about 1/8th of a turn at a time and check the chains' tightness. It needs to be uniform all the way around. If it does have a tight spot, replace your chain.</TD></TR></TABLE>

Ive read somewhere that all chains will have a tight spot, mine does, nothing extreme mind you, but tighter none the less, play is approx 1" except tight spot may be 3/4" chain has 11,000 miles with no probs and Ive only had to adjust once clean and lube religiously.

 

[Guest]

I'd say you have a stretced spot on the chain if you coast the bike down a hill and it goes crunch.....crunch.....crunch......then it is acting just like my tsubakis did after wheeling my 600 lb. fj 1200 the streched part has the pin centerlines riding into the teeth late>>>>>>>>>>>>>>>>>>>replace it.

 

[Guest]

Re: (wingnutt)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by wingnutt »</TD></TR><TR><TD CLASS="quote">I'd say you have a stretced spot on the chain if you coast the bike down a hill and it goes crunch.....crunch.....crunch......then it is acting just like my tsubakis did after wheeling my 600 lb. fj 1200 the streched part has the pin centerlines riding into the teeth late>>>>>>>>>>>>>>>>>>>replace it.</TD></TR></TABLE>
Tried that, no nasty crunch, but that certainly doesnt rule out a stretch. It rides just fine on the street after my ride just a few mins ago, but it still slaps around and knocks on the stand. WTF.

 

[Guest]

Maybe try pulling it off the sprockets and pivoting each joint independently. You may discover a bent pin and dennis kirk has the links and tool if you need to replace single peices P.S. (did I spell tsubaki correctly?)

 

[Guest]

If Its Ok On The Street Who Cares About Ridin
On The Stand!!!
Just Replace The Chain And Get Over It!!!!

 

[Guest]

Re: Nasty knock of the chain... help (jbowers24)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RC51ing »</TD></TR><TR><TD CLASS="quote">If you don't have a load on the wheel (running while on stands) you should/will experience alot of chain slap and back lash. Be sure you have the recommended slack in the chain ( if you not sure how to check that it should be in the manual), make sure the chain is still flexible between every link, then take it for a ride and see how it is. </TD></TR></TABLE>

Noticed the same thing on the stand - once I noticed the noise I stopped immediately. The drive line is designed to run under load, therefore on the stand there is slack on both sides (top & bottom) of the chain allowing for extra lash in the rear drive (chain). I know my chain is not wore out (8000 mls) so I would have to say this is normal on the stand.

 

[Guest]

Another thought. If the person who owned the bike before you installed new sprockets as well as the chain, one of them may be on backwards messing up your chain alignment. Look for arrows on the sprockets or take the chain off the sprockets and eyeball it from the rear. It is pretty easy to tell, don't ask how I know.

 

[Guest]

Re: Nasty knock of the chain... help (RSRC)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RSRC »</TD></TR><TR><TD CLASS="quote">

Noticed the same thing on the stand - once I noticed the noise I stopped immediately. The drive line is designed to run under load, therefore on the stand there is slack on both sides (top & bottom) of the chain allowing for extra lash in the rear drive (chain). I know my chain is not wore out (8000 mls) so I would have to say this is normal on the stand. </TD></TR></TABLE>
I jumped on the stand with it to simulate load, same thing.

Thanks for the other suggestions guys, I'll check em all out.

 

[Guest]

Re: Nasty knock of the chain... help (jbowers24)

I had at about 18,000 mi mark... Replace the chain and sprockets.

 

[Guest]

Re: Nasty knock of the chain... help (jbowers24)

aaaaaaaahhhhhhhhhhh...........When referring to load this means to have the rear tire contacting the pavement. The torque from the engine transferring through the trans to the sprocket, to the chain, to the rear sprocket, to the rear wheel and tire, to the ground.

Tire off the ground = no load

 

[Guest]

Re: Nasty knock of the chain... help (RSRC)

Exactly what RSRC said.

 

[Guest]

Re: Nasty knock of the chain... help (RSRC)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RSRC »</TD></TR><TR><TD CLASS="quote">aaaaaaaahhhhhhhhhhh...........When referring to load this means to have the rear tire contacting the pavement. The torque from the engine transferring through the trans to the sprocket, to the chain, to the rear sprocket, to the rear wheel and tire, to the ground.

Tire off the ground = no load</TD></TR></TABLE>
What would I do without you guys.

As you can see im hesitant to pay $ to solve something that might not be a real issue. Its running okay so I guess I'll just go until I cant go no mo'

 

[Guest]

Re: Nasty knock of the chain... help (jbowers24)

Looks like everyone covered any and all the obvious cause.

You will have slack jumping with out load when the bike is on the rear stand.
Chain could be cleaned and lubed, but still have a Kink ( Two or more links locked in a set position. Bearings are either spent at that location or guilded up with crud, muck what have you.
Or the chain has seen it's life span and just doesn't flow well because the bearings at the O-ring location between links are just plain worn out...

Another one is you have a bent tooth/fork/finger whatever you want to call it on your sprocket, or your rear tire is way out of alignment and the chain is catching the edge of your teeth and jumping into the sprocket but only holds onto the teeth for a short while and has to jump back again.

Check chain.
Check Sprocket.
Check rear tire alignment. (using the notches on the swing arm is not always a perfect match.. )
Best thing to do.. Buy two plumb bobs from Sears/true value/Ace...
step one:
Weld a 12 O'clock wheely bar on to the subframe.
2. Wheely it. ride it to a stop and leave the bike upright. Be sure to shut it off and not starve your engine of oil!
3. place a 4 foot tube/bar across your fairing stay tank bracket so it extends on both sides of your bike an equal amount.
4. Attach the casing of the plumb bob so the string can hang down perfectly straight.
5. Set the length of the weight at the end of the plumb bobs string so it it just above the ground. ( 1 CM of clearance )
6. With a tape measure or scale (not a weight scale, a measuring scale!) measure the distance on both sides of your tire from two spots front and rear of the rear tire. ( Or now it would be the top & Bottom of the bike! )

Now if you seriously consider doing this, sell your dam RC and get a F'in Gixxa, I was just F'in with ya!

No seriously there is an alignment tool for measuring the alignment of your rear tire while on on stands.. (Front and rear...)

I just measure with a scale the distance between the tire and the swing arm towards the front of the tire and rear. The front and rear measurement will not match up. You want the measurements on both sides individually Front/rear to match..

Good luck I hope you work this out..

If I just wasted your time beacuse you already fixed your issue I appologize, I am in a talkative mood and feel the need to be a wise arse....

It's time to go for a ride for me! Outta here.....


Modified by Half Squid at 10:05 AM 7/1/2005