Can get bike to run spraying starter fluid in spark plug hole but not with carb?

  • Hi any help is very helpful this is my first bike build so i'm kinda going with the flow. I've can get the bike started easily first kick when i have sprayed started fluid into the cylinder thought the spark plug hole. I have not tried starting by putting started fluid into intake to test reeds but seeing as without the started fluid and using the carb to get petrol to the cylinder it will make the spark plug wet. I'm guessing the reeds are fine. Did a compression test and got a reading of 125 psi which is good cause when i got the bike it was heat seized and after unseizing it (if thats a word) it had around 30-40 psi now the top ends rebuilt. sorry for my shit english 1. i'm tired been awake for all night :0 2. i dropped out of school but before that i got a E Grade in english so i have my reasons alright 😄 Don't hate PLZ 🙂

    i left a lot of things out that i did so if you mention them and i have done them it's better as i will go double check them anyways 🙂

    Thanks everyone for reads, Sam.

  • I would give the carb a clean and make sure none Of the jets are blocked and stick a new spark plug in!

  • used a funnel and tube and poured premix in it started first kick with choke and ran and rev'd. So i guess it's the fuel tank? weird though because fuel would flow though the petcock out the tank on rev and on the fuel maybe fuel was not flowing very well? anyways just gonna order a new tank and hope it fixes the issue

  • @perithtv Sounds like it's the carb or a blocked fuel line? So I'd check all of the fuel pipes first dude - Tanks are expensive fuel lines are a lot cheaper!!! 😉

  • @CYBER-NINJA the fuel line from pet cock to carb is ok. and tbh the tanks in terrible condition so most likely would be better to replace anyways as it's had a couple of welding jobs on it. When i brought it got it for a £100 as it was an insurance write off. So maybe theres a whole in the tank causing there to be no pressure in the petcock? but anyways it leaks fuel as well. i believe the dtr is a gravity fed petcock however so this is quite bizarre?!?!

  • It's gravity fed. Is there a mesh filter in the fuel inlet stub on the carb? Have you tried running it with the fuel cap off?

  • @perithtv As @ricky0115 said

    I would give the carb a clean and make sure none Of the jets are blocked and stick a new spark plug in!

    By cleaning the carb you will get to see if there is any debris in it. If the tank is rusty inside it, this will contaminate the fuel, so that may well be the problem? I would start at the highest point Eg. The fuel tank - Is the petrol in the tank clean? Then check fuel lines, are any blocked?

    Yes the fuel system is gravity fed, however it requires pressure from a sealed tank to allow fuel to be fed down into the carb. Therefore a rusty section or a hole in the tank from a bad weld could cause a loss of pressure.

    Is the fuel coming out of the fuel cock clean? If they are all good, then I would look at the air pipe from the filter, does that have any holes or cracks? Is the air filter clean?

    Is the fuel/air mixture correct? If it is out of balance that will cause bad starting problems. Check that the mixture screw is not faulty? Is the butterfly in the carb opening freely?

    I would perform many checks before you go splashing the cash, as it may be just a cheap and simple fault causing the problems???

  • Could it be clogged fuel tap? Try drain the tank into clear container and look for any signs of dirt , see through filling hole if there is anything inside the tank. Could be rust too

  • Theres no pressure in the tank, theres even vents in the fillercap to prevent it from happening.

  • on the right side of the tank under where the plastic attaches to the right side there is a pretty sizeable hole in the tank. so i put some jbweld on it and let it dry. then gave it a couple twist of the throttle as well as 3 priming kick. got top dead center and started first kick so i guess it the tank? i don't really feel like fixing this tank IE paintin it and all so i really do think it comes down to buying a new one

  • @perithtv Good luck, new they are probably discontinued, and any you do find will no doubt cost a bomb!

  • Is their a washer under your main jet if not that might be the problem