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Engine noise
LBMEFM - 4/1/09 at 08:43 PM

I know it's difficult to diagnose engine problems without hearing them so this is a bit of a long shot. My Fireblade runs very smoothly with clean exhaust and no smoke. Performance seems ok too. However, there is a type of metalic scraping noise at the same speed as the engine revs. Any commen faults these engines suffer from.

A1 - 4/1/09 at 09:06 PM

are your cams etc okay? you could try finding the noise with a screwdriver or bit of bar to listen for it...

jonesier1 - 4/1/09 at 09:23 PM

cams turn at twice engine speed,so if the noise is intime with rpm then prob not cams.

daviep - 4/1/09 at 10:55 PM

quote:
Originally posted by jonesier1
cams turn at twice engine speed.


NO THEY DON'T!!!

Cam turns at 1/2 engine speed.

The screwdriver/stethoscope idea as mentioned often works well.

Cheers
Davie

bigrich - 4/1/09 at 11:36 PM

camchain tensioner or slipper pad fractured, does the noise reduce or clear at higher revs

maximill666 - 5/1/09 at 01:18 AM

893 & 918cc fireblade motors suffer from carb chatter, where the tolerance on the carb sliders is so large they chatter at low rpm & the noise goes away above 5k rpm.

Also the 918cc motors suffer from piston slap

Both are common fireblade traits & nothing to worry about

Bobyspit - 5/1/09 at 03:14 AM

What Blade engine?
Where in the engine is the noise coming from? is there metal filings in your oil?
Rob