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General => Technical | How To => Topic started by: Stig / Major Tom on January 10, 2018, 12:38:18 AM

Title: Hard starts & valves ??
Post by: Stig / Major Tom on January 10, 2018, 12:38:18 AM
We get a lot of posts from owners of 125cc and smaller scoots who have engines that need many kicks to start ....failed electric starts, or stall frequently after their morning hard-starts.

How many of these scooters might be suffering from valves which are in need of adjustment?

Other than valve clacking noise of too big a valve lash - what are the common symptoms of out of adjustment valves?

Without a proper understanding which valves play in easy starting....we might overlook this simple fix.

Stig
Title: Re: Hard starts & valves ??
Post by: PaulF on January 10, 2018, 01:03:47 AM
I had a lot of problems with my LIKE 125 carby engine when I first had it.  It would start easy enough but when the auto choke switched off it would stall a few times before fully warm.  A few months before I upgraded I was having problems starting it up and I decided to adjust the idle screw and adjusted it so it was idling a just bit faster than when I first got it and that got rid off all the problems including the stalling after the auto choke turned off.  So for me adjusting the idle to run a bit faster was the key to a great running engine.
Title: Re: Hard starts & valves ??
Post by: GLV55 on January 11, 2018, 12:42:02 AM
I had a lot of problems with my LIKE 125 carby engine when I first had it.  It would start easy enough but when the auto choke switched off it would stall a few times before fully warm.  A few months before I upgraded I was having problems starting it up and I decided to adjust the idle screw and adjusted it so it was idling a just bit faster than when I first got it and that got rid off all the problems including the stalling after the auto choke turned off.  So for me adjusting the idle to run a bit faster was the key to a great running engine.
Good info, Paul. My carbed 150 is starting to do just what you described, so this Spring I will check my valves and try your idle screw trick if the problem occurs again. Thanks!
Title: Re: Hard starts & valves ??
Post by: Stig / Major Tom on January 11, 2018, 01:12:49 AM
Fellow with 55,000 miles on his 150 Honda scooter, with new plug, still  having developed increasingly hard start, no ability to idle issues; only runs at full throttle.
Valves never been ✔'d.
Now it won't start.
Lot's of comments about watery gas, bad gas, clogged injector, needs fuel addictive, needs fuel drained, ECU bad, etc., etc.
Problem slowly worsened --  I'm betting on valves out of whack.
Interested to see if the magic juice fixes it.
Stig
Title: Re: Hard starts & valves ??
Post by: PaulF on January 11, 2018, 02:25:17 AM
Good info, Paul. My carbed 150 is starting to do just what you described, so this Spring I will check my valves and try your idle screw trick if the problem occurs again. Thanks!

Thanks, hope it works.  Keep us informed.   :)