Hi All,

I'm hoping for some help on hearing tapping sounds only when my bike has heated up to above 1/3 on the temperature gauge.

I have looked into as much as I can and think it could be either :

1. Exhaust header gaskets or mid section leaking when hot

2. Cam Chain Tensioner wearing

3. Valve Clearances need adjusting.

As I say the bike sounds fine on idle till it heats up and then gets rattly
and sounds like the tappets are out especially around the 3-4 k rev range
and also has a loud to me vibrating which feels like the exhaust is loose.

I never noticed this problem till the weather changed for the better recently and since replacing my fuel pump which packed up with a aftermarket one.
Also note I do have aftermarket Stainless Steel Exhaust headers made/supplied by a company over here by the name of Sandy Bike Spares.

Any help appreciated on where to start on this.

 

I also have a similar problem at the moment. My chain tensioner needs to be replaced, but my valve clearances have been checked during the rebuild of my top end. I need to do a full check on the exhaust system and the bike vibrates a lot at high revs so need to sync the carbs I believe. Something I can't do as I don't have the gauges

Run your hands over the exhaust when you first start the bike feeling for any leaks, from research I've done the CCT rattle disappears when warmed up and is most noticeable at low revs on the over run. When did your bike last have a valve clearance check? I believe it should be every 12000 miles? (Or around that mileage!). Like I said though... Mine has a rattle and the valve clearances are fine. I'm spending some time in the garage tomorrow checking my whole exhaust system.

I will be interested in any responses you get!

 

Hi Fryup2000

I have no record of the valve clearances being done and my bike has 25K on the clocks
and I have recently had the carbs synced which has improved idle and running of the bike in general and now pulls cleanly from low revs.

I had my mechanic friend kindly ride my bike and he stated everything felt fine with power as he does not hang around and tests the throttle well whatever he rides!


And he could not hear the rattling noises I reported BUT they are clearly there so I have said he's Mutton Jeff!


It is rather hard to get my hands around the header pipes and have tried but not found any leaks and from what I have read noises from them are usually from start up as when the bike warms the metal should expand and close any gaps but is that always the case??

My problem does seem to point more towards an exhaust noise and looks like I will have to remove it and replace the gaskets on all joints to remove it from the equation.

and then next would be to change the CCT and then lastly valve clearances as most expensive to do and read a lot of CBRs rarely go out of their spec until high mileages.

Good Luck with your Exhaust check and I hope it solves your problem and i will have to aim to do the same as you are soon.

 

I have the same issue as the OP. I have dumped endless amount of dollars into finding my answer with no prevail. I replaced:

Exhaust
Header gasket
Valves clearances check 3 times in 1 year and they are ok
2 new cct both where fine....
Went to AMS oil oil
New ice coolant
Cleaned carbs
Had fill timing chain guides looked at


And I have yet to find a thing..... I am seriously annoyed beyond belief.

 

Do you have a video or sound clip of the noise? Might help in the diagnosis.

 

Hi CJardine,

I will have to try to capture the sound then and post up on here
Hopefully will be done for the weekend.

I am feeling more and more this is an exhaust resonance problem
and have read more on other forums regarding the Stainless Steel headers
I have on my bike with mixed reviews.
Some are stating the bike never sounds as good as the original downpipes and that they have missing mid range as do not have the balancer pipes across them.

I myself feel no missing mid range and revs through rather nicely but I am no expert on what it should feel like.

If I rev the bike up at idle through just past 6k I can hear what I think is a rather high pitch rasp and it's when you ride the bike at town speeds between 3-4 k in 2nd to 3rd gear that the (annoying to me, Don't forget my mechanic friend can't hear it! : ) ) rattling valve type sound is heard.

Once again to emphases this is only when the engine has warmed up.

Here's the Headers I have fitted and a link on it which also mention's the Motorcycle News review which had recommended them.

CBR 600 CBR600 EXHAUST PIPES DOWNPIPES FRONTPIPES FX FY NEW 1999 2000 99 00 | eBay


I got these already on the bike so thought a great bonus and better than having rotten 12 year old pipes!


I have checked all exhaust fitting and they are tight as they can be so can only suspect a resonance problem.

I will repost with the sound clip hopefully on the weekend

 

I'm liking your thinking there...

I have the motad down pipes on my with similar reviews... Will look now to see if they have the balancer pipes!

 

They should have them as shown here on ebay :

Honda CBR600 FX / FY / F1 / F2 / F3 (PC35) 1999-2000 Motad Downpipes and Collect | eBay

These are straight copy of the originals as far as I read shape wise
but maybe heavier as Stainless.

 

Here's a video i have made up of what my Bike sounds like when cold and then Hot through to 6,000 rpm from Idle.



unfortunately i have not got a fixed camera and its too hard to hold the camera whilst riding but that is when the bike sounds it's worse between 3,500 and 4,000 rpm when holding at a steady throttle (if you understand what i mean)

 

The video is set to private, I can't see it.