R50X Starting problem

[Barry]

Hi guys, i am hoping someone out there might be able to help me with a starting problem.
The scooter has been faultless until today. First time riding in the rain and after about 10 minutes the scooter stopped and i haven'e been able to start it since. The battery is only a few weeks old and has good charge. I have checked for spark and that appears ok, the cylinder top appears wet so i guess it is getting fuel. I pulled off the fuel line and the gravity feed is good and the filter is not blocked. Not too sure where to go from here.

Cheers Barry

[harry]

hey Barry,
welcome to the forum...
i suspect its water  that perhaps  got into the airbox
 let it dry out and try again.
good luck,

oilyhans

[Barry]

Thanks Harry,

I opened the airbox and found it to be fry and free from water so am a little confused.

Cheers

[harry]

spark plug wire on plug nice and snug?
plug look good , do you have a spare to swap in ?
can you kick start it?

you can spray a bit of starting fluid in the air box and give it a kick or
use the e.start   , if it runs and then stalls out its a fuel problem.
if it just won't start after a couple of tries with a hot shot its
electrical..

oilyhans

[Barry]

Spark plug wiring fits firm onto plug. Plug looks good however i have not yet tried a replacement as i don't have one to try.

I haven't tried starting fluid yet but the engine seems to turn over a little too fast for my liking, i am thinking the worst and maybe compression has been lost 
Compression guage coming so i will post the results.

[Barry]

50 psi on compression check.......only riden 2700 km.....unfortunately not the news i was wanting.

[harry]

ouch!  i was hoping it was a easy fix for you.
and yeah 50psi is way too low for the motor to fire
well  swapping out a cylinder & piston is  not all that hard to do
it might be time to go to a 70 or 72 cc kit!!
good luck ! let me know if you want stock or racing parts .

oilyhans

[Barry]

Going up in CC's sounds good  , what are the major benefits and or differences between 70cc and 72cc.

I will then need to re jet the carby i guess and if so do you have any recommendations and parts to do the job.

How about the exhaust system, i will need a better flowing exhaust preferably one that will handle 50cc and 70cc upgrade.

Cheers

[harry]

all the big bore kits are made from stock cylinders
when the cylinder is bored the cylinder skirt that fits down into
the case gets real thin and excessive heat can crack them .
 a 70cc has a thicker skirt than a 72cc .
for a first time mod a 70cc   can be a safer choice, or not  depends on how close you
come to getting  it fine tuned.

yes a pipe is critical with a cylinder and will help some on a stock cylinder
 up jetting is needed with just a pipe and then again bigger with a cylinder.
 i'm hesitant  with open filters and a first time tuner as you have to always
be adjusting and re adjusting the mix  every time the weather changes 12 degrees ,
or it goes from wet to dry, even night to day can mess you up.
heres a link to some TGB mod parts
http://whidbeyislandmoped.com/cart/index.php?main_page=index&cPath=1&zenid=88728db1820ce8b449cb56d695ad5448

 oilyhans

[Barry]

If i just upgrade the pipe for now can i use a pipe made for a 70cc upgrade on my 50cc engine so i don't have to buy two pipes. If so what sze jet do i need now for 50cc with pipe capable of 70cc engine. I am happy to purchase both jets if two sizes are required.

By the way what brand if carby does the R50X have.

Cheers

[harry]

stock carb --mikuni  12 or 13 mm

yes most pipes  can be used on both 50 & 70cc.
 you need to re jet each time you change pipe, cylinder or air box mod.
 you will find TGB mod parts here;;
http://whidbeyislandmoped.com/cart/index.php?main_page=index&cPath=1&zenid=f8a9e6850cf2975519bc849ae1dc5474

oilyhans