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Posted

Hi

I am currently playing around with my sons cs50 (02). It ran ok on its first outing for him on saturday evening (approx 6 miles) then stopped. IT wouldn't start by button but did with a kick.

Since then its been cuting out alot and now will not start at all

We have a good spark on the removed plug when you crank by button or kick start. I have strripped down the delorto carb and cleaned every thing, checked the jets etc and all seems well.

The needle valve sits all the way down inside the carb and isnt bent and runs up and down ok with the twist grip.

Do any of you clever chaps have any suggestions as what to look for to get it running again. (sensible ones please)!

Thanks

Wayne

Add 1. I have just checked the compression, while cranking it knocks the guage up to 3 bar or 47 ish psi. I dont know what it should be though.

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Posted

47psi is way too low, 100psi is a good figure. How many miles has it done? did you do the test with WOT?

if it is a compression issue you may be able to prove that with a squirt of oil in the pluh hole, this will help the rings seal(only initially) and it may then start

...Paul

Posted

Hi Paul

Thanks for your reply. I messed with engines for years but my knowledge of 2 strokes is limited.

I got this ped for him with no head a barrel on it.

I purchased a new kit and it seemed to be fine..... till now.

I tested the compression with a gunstons screw in the plug hole, rubber tube and gauge on the end affair.

I have just removed the head and barrel after your comments and found the new piston lower ring ais worn away with scoring on the barrel top and bottom faces which probably explains the low commpression.

I think Its probably worth checking the oil pump.... what do you think?

Thanks again for your help.

Wayne.

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