Yamaha Aerox YQ50 Not Starting

Hello people, I've recently replaced the right hand side crank case on my Yamaha Aerox and added a few performance parts too. Now when it comes to me trying to start the bike it doesn't want to start. the spark plug is giving a spark, it has compression, and it has petrol to the carburetor. Any help with this would be appreciated.

 

Do you mean you’ve recently split the crank case in half ?

 

Yea i took it off and put a new one on.

 

Did you replace the crank seal on that side?

 

No, i just had another look at it now and it has a small gap where is screws in, i assume this may be why it won't start. I'll take it off and use gasket maker to seal it up.

 

That’s exactly why!...it has to be sealed the whole circumferance of the case but don’t use to much sealant... you don’t want it all inside the case.

Why did you need to replace it in the first place?

 

the old one had damaged exhaust mounts so i couldn't get the exhaust on i'll get an image for you to have a look at it.

 

Here's the old crankcase https://gyazo.com/c95774a6cd1716162d35394a79e9ec8d

 

I see! Let me know if sealing the case works

 

Just finished sealing it up, had to mess about taking the cylinder off and a few other parts, i'll try it tomorrow when the sealing is set. I'll let you know what happens.

 

Nice one! should be fine, what sealant did you use?

 

Just tried it now, still won't start, i've checked the spark plug and air compression again and both are still working. I used Blue Silicone RTV Gasket Maker. The issue might be that i'm not allowing enough petrol into the carb. I also just filled the tank up yesterday because it was low on petrol. Some people are saying that sucking on the vacuum pipe and allowing some petrol to flow in might get it going.

 

You can Put a tea spoon of fuel in the spark plug hole to get it started if easier than pulling fuel pipes of ect......

 

You may of disturbed the crank seal on that side! Ideally you should of replaced them while you had it apart

 

Did you replace the cylinder gaskets or use the old ones?

 

I replaced them all, i had a full gasket set that i put on.

 

Ahh ok good

 

Shouldnt it have a gasket and not sealant between the cases?
And im a little lost, did you change the crank seal?

 

Tried it again with petrol in the cylinder still nothing, The crank seal is pretty much brand new. The crank case was sealed off with a silicone gasket when i first took it off so i just re sealed it.

 

Yes they do use gasket maker from factory for the crank case

Check the crank seals are seated properly