Hi all... wondering whether someone would have any hints where to start with this one...

I recently aquired a '90 model CBR1000F with 92,000kms last week and starting to get used to it slowly. As the 'honeymoon' period is starting to finish and perfect bike is no longer so perfect, I'm starting to notice some of the scratches on the paintwork and all noises this thing makes! LOL!

She has the typical rattles associated with the CC/CCT which are worse when cold, but still has a rattle when warmed but not as bad and seems to be a slightly different rattle to the cold rattle. I'm yet to adjust the backlash adjustment which I've been reading about.. I'll get to that one over the next weekend.

The other annoying noise I'm really starting to notice is a knocking type noise which is most noticable under load, specially just above idle. I don't think it's the clutch so much as it still makes the noise when I'm not touching the clutch... i.e. driving up our steep driveway in 1st - fast enough not to have to ride the clutch. It even does it in 2nd if I leave it in 2nd going around a moderate speed corner and accelerating away.

I notice on tonights ride... on take off, if I give it a bit more revs and gradually release the clutch the noise isn't so bad so I assume it's definatly load related. It also appears to go away after 3,000rpm.

I would best relate the noise to the type of knocking sound dud CV joints makes in front wheel drive cars, although it doesn't really appear to be a consistent beat to the knocking, it's kinda random. It's not head turning loud (yet), but really annoying and I'm worried something major might be wrong.

As far as I know last oil change was around 4,500km ago and done by a renowned bike shop in the city before being sold in their second hand show room... who knows what oil they used but it appears to be nice and clean. I can only assume they did the oil filter then as well. I was planning on changing the oil in another 400-500kms but might be worth doing it sooner if anyone thinks that could be an issue.

The clutch itself seems to work great... doesn't slip or do anything out of the ordinary... gears don't pop out into the neutral and it's easy to shift through the gears. The bike istselfs seems to run great, although does have a rough idle at around 700rpm, but the exhaust note is smooth when the revs pick up.

One more thing... front where I sit on the bike riding, it sounds as though it's coming more from the rear of the engine rather then up front, but it's a hard thing to tell with a helmet on and a fully inclosed fairing.

Thanks in advance for any help on this one.

Carl

 

First off, your idle is to low. You should be setting it to 1,000 to 1,200 RPM.

Next, what type of fuel are you using and what RPM do you hear the noise. You will hear some rattle of the balancer if you let the RPM drop to low under load. Also, some pinging will occur with improper fuel and low RPM. Do you hear the noise with the idle set to 1,200 RPM and keepingit revving? I shift at 4,500 to 5,000 RMP, which I think is at the low end.

 

If it's coming from the rear, check the chain. It could be loose and hitting something, or just plain worn.

 

I had a knock which I could notice most of the time, it turn out to be a link in the chain.
had to get a new chain and sprokets $$$ka-ching $$$

 

Thanks for the feedback guys....

Idle to 1000+rpm... roger - can fix that pretty easy!

Fuel. Well, I've only done nearly 100km on it and I put in around 8 litres of plain old unleaded - in aussieland it's around 91 octane. Should I give the premium stuff a go?

If I gear shifted at 4,500rpm I'd be speeding around the streets here! LOL! It's really only noticed on take off up to 2,000-2,500rpm after that and the initial take off load is moving it seems to dissappear. One thing I havn'ttried is to place it in a higher gear and roll on the throttle from say 2,000rpm putting the motor under load to see if it does the same thing.

Chain -I checked it before I brought the bike had about 2" total play in it. I've never had a chained bike before (always had shaft drive - gottta love em!) but it didn't appear to be excessive. Although if I pop her on the centre stand it does make a bit of noise if I spin the wheel in nuetral - kinda like a noise you'd expect with a greasy chain moving over teeth on the sprockets. Sprocket teeth look ok, no hooked teeth or too badly worn.I didn't notice a slight ticking noise though... is that normal?

Been reading up on other noise written about in these threads... I'll check the exhaust headers to see if they're all secure and just check general tightness of everything when I take the fairings off over the weekend. It's a pitty it doesn't make the noise in neutral otherwise would get closer to listen for it. Although I might be able to replicated it on the centrestand if I pop it in a high gear and let the wheel spin perhaps.

I'm pretty certain it's drive-line related, whether external (chain and sprockets) or internal (argh! Gears/chains/clutch!).

 

Um... whatkind of '$$$ ka-ching $$$'? :-S :-(

 

The bike will also make a knocking noise that goes away as the revs rise if the carby's are out of synch.

 

Hey Michnet, i only use unleaded in oz, my cbr is an 87 and have no problems, what year is yours, and where u from? pete

 

1990 - Riverland, South Aust.A few K's to your west!
I'm thinking next refuel i might try premium for the sake of it.

Ok, yeah a carbie sync is on the to-do list, as well as a valve clearance check etc... Need to save up some $ first. Still gettting over the initial cost of payment of the bike, plus new tyres soon to be fitted!! Really need to get a decent Honda mechanic to look over it... will need to take it to Adelaide for that as all the bike shops here in the country scratch their heads at road bikes! They only sell dirt/ag machinery.

 

The sound of the Bike Shops till opening $$$ ka-ching $$$ about A$400 I think
Should use standard unleaded, but I found that the bike goes good with 95E10 from IFS