sherlock

P.s It is a new spark plug , but the plug gap is 0.25 which I was unsure of , I found it on line but not 100% sure of its credibility.

Hi , I also thought it might be an air leak , but I have taken off the connection between the carb and reeds . It looks ok no cracks . Its actually my friends bike who is just starting out with trials, not saying im an expert! He has taken the carb off again this evening to blast the hell out of it with a compressor . I was hoping it would not be an air leak on the crank seal , I have never had to delve that deep yet ! I have been spoilt with my Montesa as it seems to never play up , with just oil changes , carb cleaning and new plugs every now and then . Thanks for your advice I will keep you posted .

Thanks , I will try and get a new Pilot jet and save any second guessing .

Hi all Im a proud owner of a Montesa Cota 315R and Have just got hold of a Gas Gas JTR 250 1996 So here is my dilemma I have trouble with the bike running at low revs I started by cleaning the carb , took all jets out blasted them with cleaner and can see daylight through all holes . New spark plug and air filter Bike just wont idle properly , so could the pilot jet be too small ( although it did run fine about six years ago) I wondered if its got corrosion and isnt letting enough fuel through . It will only idle with the idle revs screw in quite a bit and wont settle down to a nice pop pop pop , just revs a bit higher and them drops right down and dies. It wont then start without the choke , although once the choke is turned off it still runs , so hopefully that means it is getting idle fuel etc. the Plug gap seems small its 0.25 and on my Montesa its .080 so a big difference . Any help would be very much appreciated Marcus.