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Originally posted by alexmc22
[br]Recently I decided to check the valve clearances and found 9 were fairly bad.

If anything in this guide is wrong can someone post up because i do not want anything bad to happen to anyone who uses this guide but it did work fine.

First remove your front and side fairings. remove your tank, airbox, ignition coils, lower the radiator and remove the head cover.

To look something like this.



Now undo all the bolts to the left hand engine cover so your able to turn the engine to check all the valves. Make sure the pin doesnt fall out of the gear. Unlike my image where it had fallen out.


Now you need a set of feeler gauges I got a set from supercheap for $14 goes from .04mm to 1.0mm.


Next get a 14mm spanner and turn the bolt that was under the engine cover and turn it clockwise so you get the lobes on the camshaft in this postition. (Also on the shafts you will find IN1 through to IN4 and EX1 to EX4) The top shaft in the Inlet valves which when the engine is cooled which is should be for doing this have a gap of .16MM the Exhaust clearance is .23MM.

Place the gauges under the lobes to get the clearance if it is out change to different gauges so you can get the correct clearance so you will know what valve shims to buy. In the image you will see where the lobes need to be to get a correct clearance reading.


After doing all 16 you are left with the math of finding out which shims you need.

Example for an inlet valve clearance you got is .22mm you need .16.

.22 - .16 + 1.98 = 2.04 (1.98 being the size of the shim already installed which on the shim will say 198) The shim you would purchase to fit into the bike would be a 205 which is the closest to 204.

When removing the shafts to fit in new shims undo them in a cross pattern so you wont bend the shafts. With the oil bar throught he middle be very carefull when you take the allen key bolts out and lift it not to lose the rubber seals.

Here is an image of the valve shim put into place then you just put the bucket over the top. (I dont know if it makes a difference but mine were placed in numbers up so I did the same)


Now its time to put the shafts back in and correctly time it all.

On the right hand engine cover you will find an allen key screw a big one and a small one above it. Undo the little one on top and now turn the engine like you did to check the clearances until you see a T written on the metal inside the hole.


When you find it place the shafts like the image below. Make sure both lines with the top one the IN line and the bottom one EX face each other and are parrallel to the engine.



Now place all the holders back on the shafts and tighten in a cross pattern once again. (by cross pattern i mean something like do one bolt on in4 being the top bolt then do up the bottom bolt on in3 holders)

Then put it all back together and you are done.


I know the pics are crap and are from a camera phone but I tried.


If you need any help at all PM me or post here I will help asap.

Here is a link to the album i uploaded if you need more pics.
http://img340.imageshack.us/g/30102009001x.jpg/

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If the OP is still looking, I have a few q's.
firstly good writeup ,
I was going to attempt this on my 600rr as it's due and starting to sound a little rougher than it used to. Is it hard to find shims? what are they worth?
Also, did your bike run noticably smoother after the proceedure?
 
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These sort of threads scare me when I think of the mechanically ability I have seen first hand.

What was the saying? A little knowledge can be dangerous.
 

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And another saying is, "nothing ventured nothing gained". Actually come to think of it people say a lot of things... Fortunately I can hold my own with a spanner and have no reservations about attempting this. I'm actually looking forward to the challenge / learning experience. Just don't come and see me if i fuck something up. ;)
 

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where did you get the values for the clearances from and may i ask what the allowable error is (impedence?) ie +- .05mm..
 

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^ should be in the manual
[hr]
Valve Clearances (COLD Engine, i.e. leave engine overnight)
Inlet valves : 0.16mm +-0.03mm
Exhaust valves : 0.23mm +-0.03mm
 

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viper33 said:
^ should be in the manual
[hr]
Valve Clearances (COLD Engine, i.e. leave engine overnight)
Inlet valves : 0.16mm +-0.03mm
Exhaust valves : 0.23mm +-0.03mm
cheers i just found it aswell :)
 

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On a run-in MC14E engine, do the valve clearances tend to open up or close up? (most of my valve clearances on my 20,000klm Triumph had gone tight, but thats because of the valves bedding into the head on a new engine. Known and common for the modern Triumph engines, but is there a tendancy either way for a run-in MC14?)

Cheers.
 

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i thought cbr's had shims...why are there adjustments needed?
Metal parts wear, valves bed into the valve seats, hence swapping of the shims with different thicknesses is required and should be checked at the recommended intervals. Else you can run the risk of burning your valves if the cam clearance closes up too much. (the smaller cam gap causes the valve to open too long, creating low compression and firing through the not fully closed valve)
 

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Trackstar said:
Else you can run the risk of burning your valves if the cam clearance closes up too much. (the smaller cam gap causes the valve to open too long, creating low compression and firing through the not fully closed valve)
also coz valves cool when they close fully and come into contact with the head(heat transfers from hot to cold), if they remain open they aren't cooling down
just saying
 

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Cool, hadn't thought of that, but sounds obvious now you mention it. How long can you put off checking the valve clearances on the cibbie 250's? I know with my triumph they were getting too tight, good thing I checked it at the recommended interval.
 

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Just saw this thread now. One thing to add to this is there is absolutely no need to remove the left engine casing to turn the engine. What you do is undo the big allen cap in the 6th photo (right engine casing). Then use a 14mm socket on an extension bar to turn the engine from the hex nut inside. That way your able to keep an eye on timing mark on the flywheel while you turn the engine. Removing the left hand casing waay over-complicates things!:rolleyes:

Also read the manual and follow it to a tee and you cant go too far wrong. Oh and dont even attempt this job without a low range torque wrench!:)
 

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Speedracer10 said:
If the OP is still looking, I have a few q's.
firstly good writeup ,
I was going to attempt this on my 600rr as it's due and starting to sound a little rougher than it used to. Is it hard to find shims? what are they worth?
Also, did your bike run noticably smoother after the proceedure?
i went to do the gasket and clean the the heads silly me forgot that the lifters would fall out 14 out 0f 16 actually anyone have any ideas how to corect this matter easily i do know how to do valve clearences i think it will be a long procesess can anyone help???
[hr]
i went to change gasket and forgot to tape lifters down 14 fell on the work mat i do know how to set valve clearences but does anyone know a short cut instead of having to remove cam shafts a million times to re fit shims in orginal places what would be easier??? thanks
 

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there is no easy [im assuming you meant quick] way. unfortunately, youve stuffed up and you've made yourself a shitload of work...

if all your clearances were sweet, then it would be a lot easier because then you just need to lob them all in any old place then hope that some are still sweet and just shuffle the rest around till all are within tolerances...

if your clearances were already shite, then have fun. its going to be a long annoying procedure...

this is why you ALWAYS record on a chart what size was on which valve so that if something annoying like this happens you have something to fall back on...
 

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mootavic said:
there is no easy [im assuming you meant quick] way. unfortunately, youve stuffed up and you've made yourself a shitload of work...

if all your clearances were sweet, then it would be a lot easier because then you just need to lob them all in any old place then hope that some are still sweet and just shuffle the rest around till all are within tolerances...

if your clearances were already shite, then have fun. its going to be a long annoying procedure...

this is why you ALWAYS record on a chart what size was on which valve so that if something annoying like this happens you have something to fall back on...
i know it was a major stuffup that i have never done the clearences were fine that what i thought a lot of tedious work i wont ever make the same mistake again im confident that i will pull it off just going to take ages as ithought

[hr]
popa250 said:
mootavic said:
there is no easy [im assuming you meant quick] way. unfortunately, youve stuffed up and you've made yourself a shitload of work...

if all your clearances were sweet, then it would be a lot easier because then you just need to lob them all in any old place then hope that some are still sweet and just shuffle the rest around till all are within tolerances...

if your clearances were already shite, then have fun. its going to be a long annoying procedure...

this is why you ALWAYS record on a chart what size was on which valve so that if something annoying like this happens you have something to fall back on...
i know it was a major stuffup that i have never done the clearences were fine that what i thought a lot of tedious work i wont ever make the same mistake again im confident that i will pull it off just going to take ages as ithought
i thought maybe starting from scratch all new valves shims lifters everything might have been easier
 

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Where would be the best place to buy shims? Given I'm in Melbourne.

I suppose the issue is measuring up the shims and working out what sizes are needed and then having to wait 3-4 days for Shims to rock up. This can cause an issue if you need the bike to commute.

Any thoughts?

EDIT: oh, and do you need to purchase a new cover gasket? Or do you use crankcase sealant?
 
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