MeanOldWarthog Posted May 27, 2023 Share Posted May 27, 2023 New here so apologies if this is in the wrong place, Around a year ago i bought the above as my first bike and it was occasionally cutting out when going into first or when idling over and i simply blamed myself for being brand new etc etc. However it still does it quite regular and its nearly always when coming to a complete stop then attempting to throttle on and set away. It gets around a quarter turn on the throttle and dies, It also takes a number of attempts to start up again and its not unknown for it to take a good 10-15 seconds before it will let me select a gear and pull away without dying (this is even when the engines hot after running for a good deal of time, not ideal when on a busy 2 lane roundabout and I'm sat there like a lemon cursing the 9 hells) Even when its idling if i don't apply any revs it will die when in neutral and sat still (although I'm not sure if this is simply the age of the bike and a common fault) Throttle and clutch cable have been adjusted, Passed an MOT a few weeks back and only ever uses Super unleaded petrol. I was thinking perhaps the carb needs a good clean out but being new I'm guessing. Any help is appreciated TIA Quote Link to comment Share on other sites More sharing options...
Moderator Snakebite68 Posted May 27, 2023 Moderator Share Posted May 27, 2023 Not a mechanic but... 1/ What RPM does it idle at when warm? 2/ Does it have a steady idle when warm? 3/ Does the engine run smoothly when warm, or does it surge? Quote Link to comment Share on other sites More sharing options...
Solution 2 Wheels Posted May 28, 2023 Solution Share Posted May 28, 2023 A carb problem. 1st, on the outside of the carb there will be a Philips screw with a big visible spring around it, this is an air mixture screw, turning it left or right will up and down the idle of the bike by really small amounts. Turn it right by 1/4 a turn and wait a min for the bike to react, if the revs rise a little without the bike being too reved up, it should idle. If it dies straight away try turning to the left 1/4 turn and wait for a reaction. Always remember where the screw was set at before you start turning it. If this doesn't make the bike idle probably you will have to clean the carb. Inside the carb there are 3 jets you have to clean spotless,,,, idle jet,,,,pilot jet,,,,and main jet. Obviously the idle jet is for idling and starting,,,,pilot jet is for throttle from idle to nearly 1/2 throttle and main jet is from half to full throttle. This is a rough explanation but that's what there for. Every bit of inside the carb needs to be really clean. The fact your bike dies coming to a stop, then hard to start, then won't take throttle to let you pull away tells me it's your jets BUT it's definitely worth a try first with the air screw, you might get lucky,,,,, maybe it was never adjusted from factory settings and after all the years it needs to be tweaked. Google carb cleaning before you touch the card and it's delicate setting Best of luck 1 Quote Link to comment Share on other sites More sharing options...
MeanOldWarthog Posted July 5, 2023 Author Share Posted July 5, 2023 Thanks everyone, carb and valve is nackered and dumping fuel. Source and fit a replacement, just need to see how much it will cost now thanks again Quote Link to comment Share on other sites More sharing options...
Moderator Snakebite68 Posted July 5, 2023 Moderator Share Posted July 5, 2023 Well, don't forget to come back and let us know how it goes... 1 Quote Link to comment Share on other sites More sharing options...
MeanOldWarthog Posted July 15, 2023 Author Share Posted July 15, 2023 All sorted, been on a few shorter trips since the solution and absolutely no problems. Carb was rebuilt (was absolutely filthy, may explain why why the previous owner sold it cheap with almost no riding on it) valves etc replaced. Thanks everybody Quote Link to comment Share on other sites More sharing options...
Moderator Snakebite68 Posted July 16, 2023 Moderator Share Posted July 16, 2023 Cool! Grats I've really gotta get my Thunderaces carbs done, who knows when they were last cleaned/tuned... lol Quote Link to comment Share on other sites More sharing options...
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