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jakeeeeey
27-08-2014, 04:52 PM
Hi all. I'm new this this whole mini moto thing. I bought a Chinese dirt bike last week. Had to replace the pull start and carb as they were broken.
I've fixed the bike up now, only it won't start. I have fuel in the tank, I get a spark, tested the compression and the air filter is clean. Checked the cylinder and piston and they both seem fine with good piston rings. Checked the inlet gasket whichbis in tact.
Any suggestions?
Only cost me 10 but wouldn't mind getting at least one run on it!

simsimmer
27-08-2014, 05:02 PM
Hi,have you tried starting it with the choke on?

Cheers Simon

jakeeeeey
27-08-2014, 05:09 PM
Thanks for replying Simon. Yes I have tried starting it with the choke on

jakeeeeey
27-08-2014, 05:27 PM
There are a few wedges missing from the flywheel. Would this be whybit won't start? Also killswitch cable was broken. I did tape it back together again

Shep0479
27-08-2014, 06:23 PM
Have you tried it with the kill switch disconnected?

jakeeeeey
27-08-2014, 06:32 PM
Yes. Still doesn't start. It sounds like it wants to. Could it be the valve reeds or inlet manifold maybe?

Shep0479
27-08-2014, 06:33 PM
Carb? Over jetted ?

jakeeeeey
27-08-2014, 06:33 PM
I've cleaned the carb a few times using white spirit too

Shep0479
27-08-2014, 06:34 PM
Are you adding some throttle when starting?

jakeeeeey
27-08-2014, 06:35 PM
I've tried no throttle. Half. Full. Tweaked the idle screw

Matt9393
27-08-2014, 06:53 PM
Mine wouldn't start the other day after I put a new plug in so I put the old one back in still wwouldn't go, I took the air filter off and went first pull

jakeeeeey
27-08-2014, 07:01 PM
Tried mine with and without the filter. Must be a stubborn bike!

cuttsthedon
27-08-2014, 09:08 PM
can you remove the pullstart and try starting it with a drill?

jakeeeeey
27-08-2014, 09:09 PM
Tried that too :/

cuttsthedon
27-08-2014, 09:19 PM
is the plug wet when you're trying to start it? i.e. fuel getting through?

jakeeeeey
27-08-2014, 09:21 PM
Fuel is getting through to the cylinder.

cuttsthedon
27-08-2014, 09:22 PM
There are a few wedges missing from the flywheel. Would this be whybit won't start? Also killswitch cable was broken. I did tape it back together again

I'd have thought the "wedges" or fins missing from the flywheel would cause it to vibrate when running as it may be unbalanced. I shouldn't think it would stop it running though.

jakeeeeey
27-08-2014, 09:25 PM
It's stumped me. I have a Cag mk1 as well. Runs fine. Starts first pull. The dirt bike has the same engine. I've swapped parts over. Mk1 still starts. Dirt bike won't. Going to try putting half a cannot fuel into the cylinder tomorrow and see if it fires up

cuttsthedon
27-08-2014, 09:27 PM
If you have tried a "definitely" good plug then I'd guess at reeds or a duff coil pack. I had a cag when I first started riding and the coil was the problem with it not starting. I even had a good spark so didn't think about the coil but it was changed by an expert and the bike was fine after that...
Is the exhaust flooded with fuel?

jakeeeeey
27-08-2014, 09:35 PM
Yeah has a good spark. I've ordered new reeds and inlet. Also ordered new coil and flywheel. Exhaust isn't flooded as I took it off to check this evening. At least the cheap bike has cheap parts! All parts together came to less that 10 quid

jakeeeeey
29-08-2014, 05:47 PM
UPDATE
Managed to get the bike up and running. Left it for a day and tried again. Started first pull.

1armbaker
29-08-2014, 06:37 PM
Sounds like you flooded the engine thats why it wasnt starting

jakeeeeey
29-08-2014, 06:40 PM
Don't think it was flooded. There was a leaf on the between the reeds and the cylinder head. Noticeable how it got in there in one piece though

Shep0479
29-08-2014, 07:16 PM
Glad it's sorted.

jakeeeeey
29-08-2014, 07:17 PM
Oops. I meant not sure how it got there!