How to set Valve clearances on horizontal engines.

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sean01

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disregard the sticker mate..

use whats stated in this thread... it works for all horizontal china engines.

.0019/.002 thou is no where near enough for these.. maybe on a hot setting but def not for cold.
 

BentWookiee

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Ok thanks sean,
Thought it was worth asking and might save some others from having to ask the same question as I have been waiting for a reply from Atomik ... Still waiting hahaha.

Cheers
 

t00l

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forgot to post back a thanks!
after two bad attempts a few months back I finally got around to give it a third crack and found that the exhaust end was about 2mm open lol

after a quick adjustment its all back up and running like new :D
 

colta51

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great guide! but one question dont diffrent motors use diffrent size gaps? or is this a fairly unerversal thing?
 

Sunnysideup

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Many Thanks Thumper 140

I found your very clear tutorial on Valve Clearances extremely useful.

Thank you for the effort and sharing your knowledge.


Jason
 

Jammo

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hey , where can i get feeler gauges, this will be my first time doing this, i hope i don't reck my engine..
 

rhysieboyy

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supercheap,autobarn,repco any good auto shop will have them.
 

Hock

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do you have to remove the spark plug before you do work on the engine like adjusting the valves? saw in a vid that u did
 

eichkay

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do you have to remove the spark plug before you do work on the engine like adjusting the valves? saw in a vid that u did

No you dont,

On high compression motors it will make life easier turning them over by hand but its not that difficult anyway
 

Hock

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Did my Valve's yesterday. Is it normal for quite a bit of oil to come out of the exhaust valve thing when u unscrew it.
 

hman

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Did my Valve's yesterday. Is it normal for quite a bit of oil to come out of the exhaust valve thing when u unscrew it.

yeah mate that is normal. the valve cover is dished so the oil cant flow back into the bottom end so it goes all over your hands and floor. good fun!
 

Nollmeister69

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Hi Guys I'm only a novice at this. My kids are better than me but guys like Thump*140 giving great explanations and even better, pictures, should be proud of yourselves for helping us novices like you do. Thanks and keep up the good work
 

motoanth

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Hi I've got a pitpro 50cc and when I am looking for TDC my cam dot lines up at 3 o'clock and the flywheel T mark at a 12 o'clock notch in the casing is this right.
I set the valve clearance the bike starts and runs fine where before it would just start and stall but now I have a loud ticking noise. So have I just set the gap with the cam in the right spot as most threads I've read say the dot should be at 9 o'clock?


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my67xr

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Was that on the compression stroke ?
Sound's like your engine was still 180° out, turn the flywheel around a full turn from where you were at.
Hopefully you haven't bent the valve's on the piston.

Were the rocker's a little bit loose when you went to adjust them?

Yeah when you go to set the rocker/valve clearance's, the cam marking point's to marking in the head at 9 o'clock, t marking on flywheel should line up with marking in case at 12 o'clock
 

motoanth

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I'm not sure it was on the compression stroke but I was watching the rockers to see when both didn't compress the spring and I put a screw driver through the plug hole to check the piston was at the high point.
If both valves a closed it should be on the compression stroke?


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