Yamaha Jog lc

[cyclopaul]

Bought this a while back for my daughter but the bike will fail to start sometimes. Most of the time its fine but every few weeks it just wont start either from cold or after a few minutes of being turned of when I try to restart.

Have to wait around 20-30 mins for bike to restart

Have changed the cdi unit and plug but same thing happens any clues really grateful!!!

[Taught2BCauti...]

Try removing the spark plug and check the condition of the electrodes and the insulator, and measure the gap (with a feeler gauge).

Also check the HT lead back to the ignition coil, including the plug cap - looking for signs of cracking or perishing, or signs of damp or condensation.

Have you tried to start it by using something like 'Bradex East Start' sprayed into the air intake?

If this helps to make starting easier, you might have a problem with muck in the carb.
____________________
Honda Varadero XL125(V8)
www.TheFutureIsHere.eu

[cyclopaul]

Thanks so much for the tips I will try these things at the weekend when I get a moment. its starting to frustrate!!

[Iain.]

1. When it stops and refuses to start, remove fuel cap and try spinning it over. If that fixes it, blocked tank breather. Check coolant level/flow, could be overheating and nipping up.

2. Check operation of vaccum tap. Suck on the vac hose, look for good flow of fuel down the lines. When they start to fail you'll get poor flow as they don't open propperly causing it to cut out.

3. Open carb drain screw, again suck on vac hose and look for good flow of fuel pissing out the float bowl.

4. Remove carburettor, remove float bowl. Clean all muck out the inside of it with carb cleaner, blow through all jets with carb cleaner.

5. If EGR system is still present, check condition of valve & blank it off if less than perfect.

6. Check condition of air filter.

7. Check operation of automatic choke - https://www.pedparts.co.uk/blog/automatic-choke-unit-50cc-mopeds

8. Drain tank, re-fill with fresh fuel.

9. If it still does it, that'd be major issues. Compression test it (with a gauge, not your finger over the plug hole.) and report findings. Worn cylinders aren't an expensive or difficult part to swap out, inlets and reed valves are also very cheap.

CDI units never really go wrong, same with plugs/caps etc very rare to fail....but y'know, if there's a black box you don't really understand it's always best to change that out before checking anything out that's a common failiure