My usual bike mechanic fully booked until the new year. He will try and fit the GSX in for swapping the tyre on Wednesday, but won't have time to look at the plug fowling problem. I've taken the air filter off (as suggested), but still the same. Even when the engine is nice and warm, the throttle is as flat as a witches tit. I can also get some impressive backfires too. So, is there any one capable[1] and with in limping distance to Grange-over-Sands, who can take a look the GSX and possibly fix it? [1]I have a mental image of riding to a UKRM'ers house miles away, then they walk around the bike and admitting the know fuck all about bikes.