Valve Clearances

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Jay1200
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Valve Clearances

Post by Jay1200 »

Hello all
Just done the clearances and I have a few that are tight
Is it best to go for mid limit when getting new shims?
Not all need doing so if say the clearance on pot one inlet is different to pot 3 inlet, it wouldn't matter would it?
As long as they are in tolerance?
Or is it best to have all clearances equal for inlets then again for exhaust?
Thanks for your time
Neosophist
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Re: Valve Clearances

Post by Neosophist »

as long as all 16 shims are in tolerance it doesn't really matter if they are different size of tolerances.

When they leave the factory Honda set them all to the middle range.

Since shims tend to tighten up over time I generally set mine to the looser end of the tolerance range.

If you have a meaurement of all of the shims in the engine and the current clearnaces you can often find you can swap a few around to get your desired clearnaces without having to buy all new shims.

i.e replace a 2.8 with a 2.75 and put the 2.8 where a 2.9 was etc.
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Jay1200
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Posts: 49
Joined: Fri Mar 18, 2016 7:37 am
Bike owned: gsxr 750, drz400, nc30
Re: Valve Clearances

Post by Jay1200 »

Thanks
I'm going to work out the current size shims and what I need to change it to tomorrow
I have a few on bottom limit. Shall I just change them as well?
Neosophist
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Re: Valve Clearances

Post by Neosophist »

Jay1200 wrote:Thanks
I'm going to work out the current size shims and what I need to change it to tomorrow
I have a few on bottom limit. Shall I just change them as well?
If yuo dont change them you risk them becoming slightly tighter by the time you do your next valve clearance job, they probably wont be super tight but out of spec.

For peace of mind its probably easiest to change them, especially wheil you have the engine apart.

See if you cant swap shims aroudn first, it often saves buying new ones.
xivlia wrote:i dont go fast on this bike so really do not need a rear brake.. /
vic-vtrvfr wrote:Ask xivlia for help, he's tackled just about every problem u could think of...
Jay1200
Settled in member
Posts: 49
Joined: Fri Mar 18, 2016 7:37 am
Bike owned: gsxr 750, drz400, nc30
Re: Valve Clearances

Post by Jay1200 »

I cant sync carbs as I have to wait a week for a new radiator now so I might as well change the other bottom limit shims.
I have 3 left over and luckily my local dealer sells them.
Jay1200
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Posts: 49
Joined: Fri Mar 18, 2016 7:37 am
Bike owned: gsxr 750, drz400, nc30
Re: Valve Clearances

Post by Jay1200 »

Thanks for your help

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