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General Chat - Weekly Rides, Bike Discussion, & More . . . => The Garage => Topic started by: dearmash on September 09, 2009, 12:56:30 PM

Title: cbr 600 f4i low speed knocking
Post by: dearmash on September 09, 2009, 12:56:30 PM
I've been noticing this off & on for a couple of weeks now.  Just when starting from a standstill and only up to about 4-5k rpm in 1st gear, there's a couple of noticeable knocks coming from below.

Any comments, suggestions, ideas?
Title: Re: cbr 600 f4i low speed knocking
Post by: MotoPutz on September 09, 2009, 03:57:57 PM
Without hearing it I couldn't begin to guess...
Title: Re: cbr 600 f4i low speed knocking
Post by: mikey on September 09, 2009, 09:48:11 PM
possible ignition ping?  are you getting cheap fuel? maybe fill it up with chevron or shell 91oct
Title: Re: cbr 600 f4i low speed knocking
Post by: mikey on September 09, 2009, 09:50:02 PM
and get some news park plugs  ;D
Title: Re: cbr 600 f4i low speed knocking
Post by: JetFueler on September 10, 2009, 12:21:12 AM
Hopefully not a rod bearing.  Make sure oil level is up to par.  The bad fuel could be it too.  Try using atleast 91 octane or some racing fuel.  100 octane is great stuff.  VP or Sunoco.
Title: Re: cbr 600 f4i low speed knocking
Post by: dearmash on September 10, 2009, 01:35:04 PM
The bike has new (<1k miles) oil, nothing but 91 shell or chevron.  Spark plugs are something I think I can check and probably are original, if that's a culprit.
Title: Re: cbr 600 f4i low speed knocking
Post by: SPL on September 11, 2009, 11:04:33 AM
Quote from: dearmash on September 10, 2009, 01:35:04 PM
The bike has new (<1k miles) oil, nothing but 91 shell or chevron.  Spark plugs are something I think I can check and probably are original, if that's a culprit.

Got your PM, will be calling you shortly. Its not rod bearing my friend. 
Title: Re: cbr 600 f4i low speed knocking
Post by: dearmash on September 11, 2009, 01:03:26 PM
Quote from: Superbike Performance Lab on September 11, 2009, 11:04:33 AM
Quote from: dearmash on September 10, 2009, 01:35:04 PM
The bike has new (<1k miles) oil, nothing but 91 shell or chevron.  Spark plugs are something I think I can check and probably are original, if that's a culprit.

Got your PM, will be calling you shortly. Its not rod bearing my friend. 

Glad to hear it, sounded expensive  :o  lookin' forward to hearin' from ya.  Thanks in advance
Title: Re: cbr 600 f4i low speed knocking
Post by: dearmash on September 17, 2009, 10:12:52 AM
Just to update myself & maybe others.

There's a chance that this is a broken tooth rattling around in my transmission.  Now I just need to figure out how to verify & then how to fix it.
Title: Re: cbr 600 f4i low speed knocking
Post by: MotoPutz on September 17, 2009, 10:15:57 AM
Spliting the case...


No fun.
Title: Re: cbr 600 f4i low speed knocking
Post by: TWF on September 17, 2009, 12:02:31 PM
Quote from: dearmash on September 17, 2009, 10:12:52 AM
Just to update myself & maybe others.

There's a chance that this is a broken tooth rattling around in my transmission.  Now I just need to figure out how to verify & then how to fix it.
don't think so
Title: Re: cbr 600 f4i low speed knocking
Post by: Yard Sale on September 17, 2009, 04:34:14 PM
Yeah, it might rattle around for a nanosecond until it worked its way between gear teeth and locked up your transmission.

(http://2strokeyardsale.smugmug.com/photos/579791031_EbXne-M.jpg)


Do you have an ignition advancer of some kind on the bike?
Title: Re: cbr 600 f4i low speed knocking
Post by: dearmash on September 22, 2009, 03:52:53 PM
Quote from: Yard Sale on September 17, 2009, 04:34:14 PM
Yeah, it might rattle around for a nanosecond until it worked its way between gear teeth and locked up your transmission.

[img]

Do you have an ignition advancer of some kind on the bike?

My knowledge of an ignition advancer is restricted to the following google searches:
http://www.google.com/search?q=ignition+advancer
http://www.google.com/search?q=ignition+advancer+cbr+600+f4i

I haven't put anything on to the bike myself, but the previous owner did put on a power commander, though there isn't anything I've seen on the bike with "Ignition module".
As far as a mechanical ignition advancer, I'd have to call up the previous owner or look myself (how hard?)
Title: Re: cbr 600 f4i low speed knocking
Post by: Rand on September 23, 2009, 05:04:23 PM
Make sure it's not something simple like an exhaust leak.  They can make a sound similar to a knock at low RPM.
Title: Re: cbr 600 f4i low speed knocking
Post by: karneybo on September 23, 2009, 09:43:24 PM
is it can also be the cam chain tensioner and what your hearing is the valve lash.  Cbr f4 and f4I's the cam chain tesioner are known to go bad ( i know mine did ).
Title: Re: cbr 600 f4i low speed knocking
Post by: mikey on November 10, 2009, 10:08:34 AM
Quote from: karneybo on September 23, 2009, 09:43:24 PM
is it can also be the cam chain tensioner and what your hearing is the valve lash.  Cbr f4 and f4I's the cam chain tesioner are known to go bad ( i know mine did ).

mine did 89 F2