I have a Malossi tuned 210 that has started to make a very distressing noise. It’s been tuned by Taffspeed and has a SIP Performance exhaust, all fed by a 30mm on a Malossi reed block. It’s run fine up to about a month ago, but suddenly started making a noise like there is dirt in the barrel or exhaust at about half throttle. This noise isn’t there either below or above this point and doesn’t seem to affect the performance.
A few people have suggested that it is pinging, but I had the head off last night and can see no sign of this, also the plug is the correct colour.
I’m open to suggestions as it’s stumped me??