Engine bogging and backfiring..

[agrmodz]

I think that's your best bet right now. Is the racing carb the delorto clone with auto choke release or the cns carb with the separate choke cable. I might be able to give you a starting point for jetting if I know the elevation and average temp. where you live.

Weather in Adelaide. Adelaide experiences mild winters and a warm, dry summer. It has an average maximum temperature of 29°C (84.2°F) in summer and 15 - 16°C (59 - 60.8°F) in winter. Plan ahead with our information on temperature and rainfall.
I think i may have found the problem though, the bit on the carby where the fuel hose connects to supply the fuel had a big hunk of mud in it, i also read on a different forum that back firing is very unlikely and it is probably the fuel igniting to early or to late... dude to it running lean or not enough petrol to air... The main jet bit also had a little bit of gunk in it. everything is clean out and i'll be giving it a shot very soon, but as for the jets on the racing carb, what would you recommend?

 

[agrmodz]

FIXED!! The carby was clogged with junk so it wasn't getting enough fuel for the air so it was igniting a small bit of fuel but it had more air than anything, now it goes about 42 mph, also the but that the float pushes up on the carby to stop fuel from coming in was getting jammed occasianally.. I'm going to keep this thread alive just incase someone else ever has this problem. ---

Also what would be the right jet for this kind of weather? Weather in Adelaide. Adelaide experiences mild winters and a warm, dry summer. It has an average maximum temperature of 29°C (84.2°F) in summer and 15 - 16°C (59 - 60.8°F) in winter.
Thank you!!

 

[gary55]

FIXED!! The carby was clogged with junk so it wasn't getting enough fuel for the air so it was igniting a small bit of fuel but it had more air than anything, now it goes about 42 mph, also the but that the float pushes up on the carby to stop fuel from coming in was getting jammed occasianally.. I'm going to keep this thread alive just incase someone else ever has this problem. ---

Also what would be the right jet for this kind of weather? Weather in Adelaide. Adelaide experiences mild winters and a warm, dry summer. It has an average maximum temperature of 29°C (84.2°F) in summer and 15 - 16°C (59 - 60.8°F) in winter.
Thank you!!

Well it looks like you are at sea level with perfect weather, and beautiful country, must be awful. according to the jet correction chart that has worked well for me your jet should be good, and correctable through needle adjustment. 42 mph sounds pretty sweet. I tried to upload the chart for review. Good to hear your on the road again.

 

[Ahmad Darwish]

it only started to happen today, the motor is going extremely slow.. (10km) and is bogging. then it back fires, i pulled the clutch in after the backfire and the engine cut out and it just keeps doing the same thing...
Earlier on i thought i heard some tinging noises but i'm not sure.. Any help is appreciated!!

Probably a blown head gasket, messed up carb jet, Choke leaver might be stuck, Bad gas mix, warped cylinder head, there can be alot of problems...

 

[agrmodz]

Probably a blown head gasket, messed up carb jet, Choke leaver might be stuck, Bad gas mix, warped cylinder head, there can be alot of problems...

The bit where the fuel line connects to the carb was full of gunk..

 

[Guest-476390]

Would running it with an air leak in the carby cause it to do this? Too much air to fuel?

You bet it would! If it's cold outside you can actually see the leak puff out by the carb! I'm telling you now, a helicoil is going to be your new favorite tool if this is going to be your new hobby lol... once you replace all the intake holes with helicoil, you wont have to worry about it other than bad/worn gaskets...

 

[gary55]

You bet it would! If it's cold outside you can actually see the leak puff out by the carb! I'm telling you now, a helicoil is going to be your new favorite tool if this is going to be your new hobby lol... once you replace all the intake holes with helicoil, you wont have to worry about it other than bad/worn gaskets...

The Question you're advising on is 3.5 years old. Read the dates.

 

[BOSS]

Would running it with an air leak in the carby cause it to do this? Too much air to fuel?

Yes

 

[Guest-813133]

i need help, 50cc engine starts and runs, but at half throttle it runs great, where as full throttle it bogs down backfires and slows to a near stop...

 

[Wrench]

i need help, 50cc engine starts and runs, but at half throttle it runs great, where as full throttle it bogs down backfires and slows to a near stop...

Did ya read this thread? Your (problem) post sounds just like what started this thread and he fixed his bike