Clunk by left footwell???

[ZapeX2]

Hey fellas... I'm trying to track down a "clunk" for lack of a better term that I had on last two rides. It is felt on my left foot. Only when taking off slowly. I don't feel it at any other time... Only when taking off slowly. It's not ratcheting, skid is all tight, wheels are good. I've checked all the obvious. My set up is 2006 Apex, Zx2 skid, 1.5" crossover track. It doesn't do it on the stand. The clunk only happens once and it is within the first 5 feet of travel. I have about an inch of sag in my track now, I could try tightening it up and see if it makes a difference but I'm doubtful. I'm going to check the jackshaft bearing this afternoon, serviced it end of last year though. ANY... suggestions are much appreciated. This one has got me stumped..... Thanks...

 

[RX-1MAN]

I just got home from a 4 day 740 mile ride and was feeling the same clunk. Going to be looking into it ASAP. Curious what others may have found in past. Thinking maybe belt missing a chunk? Don't think jack shaft bearing as I had one go before and it was a vibration at speed. Also had drive shaft bearing go before and that never gave me this clunking I'm feeling.

 

[APEX 06]

Check your speedo bearing and driveshaft.

 

[mr. shide]

Mine is a 2011 apex se. Brand new. It does about half the time when i come to a stop then take back off. I think its either the secondary clutch re-setting or closing completely or its just the natural freeplay/slack in the entire drive system. My 06 gt did it as well. It doesnt happen all the time though. Everything is tight and adjusted to specs.

 

[RX-1MAN]

Just looked at sled. Found lock nut on jack shaft bearing came loose! No threads left on nut. Dealer just replaced this bearing year before last, guess they didn't get nut torqued properly. I'll be calling them tomorrow to get this taken care of.

 

[STAIN]

Also check the lock collar on your speedo side drive bearing. I have seen one of these loosen and make the exact noise you describe.

 

[ZapeX2]

Went out this afternoon and took the secondary apart, checked speedo bearing, jackshaft bearing, chain tension, everything in the skid. Nothing was suspect at all. Everything is tight, tight, tight. took it out for a run around my place, couldn't get it to clunk again, go figure. I will ride it like I stole it this coming weekend and see how it is. Thanks for all the replies, much appreciated...

 

[mr. shide]

Im gona check my speedo and jackshaft bearing collars this eve to make sure they werent loose from the factory to be safe. So its the collars that were loose? Any pics of what you had to tighten up or checked so i know what to look for exactly?

 

[STAIN]

you will see a black coller that locks the bearing to the driveshaft on the left side. Make sur that coller is locked and tightened. They use torx head screws for lock screws

 

[heat exchange]

I was told that the clunk was from the transfer rod in the mono suspension.You need to replace the plastic stops inside.But Zape has a ZX2 skid so that doesn't apply then.

 

[mr. shide]

Mine is a new sled. It maybe the secondary clutch fully
Closing upon takeoff from a dead stop. Only does it occasionally. Never does it if i take off slowly or from a rolling start. Ill check those bearings though to be
Safe. Theres always some freeplay in a system with mechanical reverse so some of it may be
Due to that? My track was a bit too loose as well.

 

[BlueByYou2000]

I was told that the clunk was from the transfer rod in the mono suspension.You need to replace the plastic stops inside.But Zape has a ZX2 skid so that doesn't apply then.

This is true, there is definetely a clunk at lower speeds on bumps with the Monoshock.

 

[mr. shide]

Sometimes you will feel a clunk from the skid if your limiter strap is set way loose. Going ove big bumps or over berms by a road crossing or something. Thats just the
Skid
Dropping down.

 

[heat exchange]

I guess it would be easy to remove the transfer rod to see if it goes away.You can get to get the skies in the air for fun too.

 

[stomper]

I guess it would be easy to remove the transfer rod to see if it goes away.You can get to get the skies in the air for fun too.

Been there done that, and it was funnnn.....
Can't help with the left foot well clunk but yes, my wifes mono skid clunks at slow speeds also.