heys guys been having some proplems with bike running hotter than normal, think i have tracked ti down to the bottom rad being blocked. So decided to check over the whole bike vavle clearances are all bar 2 out of spec, anyone local a dab hand at these? or will be ok to run as it is?........... INlets should be 0.12-0.18mm and exhaust 0.21-0.27mm

When you say 0.10 to 0.15 does that mean your feeler gauges aren't accurate enough?
For me I go as accurate as possible and measure the shim itself.
That way you can rearrange the shims.

Is measuring the shim itself not pointless? Are you not trying to find out what the gap is, not what you currently have in the gap?

tlnut wrote:heys guys been having some proplems with bike running hotter than normal, think i have tracked ti down to the bottom rad being blocked. So decided to check over the whole bike vavle clearances are all bar 2 out of spec, anyone local a dab hand at these? or will be ok to run as it is?........... INlets should be 0.12-0.18mm and exhaust 0.21-0.27mm

As above, are you feller gauges accurate? You need a set where you can make increments of 0.01 at a time.

Even with a smaller set you can usually put two together.. i.e 0.09 + 0.06 to get 0.15.

You need to be accurate with it, theres only a small tolerance. Then measure the all the shims too.

From here you can work out what shims you need to buy and what you have, so you can swap some around maybe.

I did my clearances the other week, still had factory shims in it, replaced all 16 but only needed to buy 14 as I could re-use two of them.

Yeah my gauges go from 0.05 upto 0.80. Where can I get more accurate gauges from? I take it it's not good with tight clearances

tlnut wrote:Yeah my gauges go from 0.05 upto 0.80. Where can I get more accurate gauges from? I take it it's not good with tight clearances

It sounds like you have enough gauges but have just measured it wrong?

0.05 - 0.10 isn't a proper measurement.

Start with 0.05 then 0.06 and so on until it doesn't fit to get your gap.

machine mart do feeler guages - i hated doing the clearances on my bike, not because it was hard, it was all the maths !

From memory when i did mine, you will need to measure the shims that need changing - in order to know what to replace it with. I Got a micrometer from machine mart too........... then had to quickly figure out how to use it!

some one on here had an excel document that did all the maths for you , you just had to put in the exsisting shim size and the current gap in the certain box inlets/outlets and it gave you the shim size you needed , cant remember who it was tho

I make a big chart.

Get all the clearances accuratly first and the shim sizes for each valve too.

Ie.

Front Exhaust:

Gap: 0.20 0.18
Shim: 2.35 2.38

New Shim: 2.30 2.30
New Gap: 0.25 0.26

Your range is 0.21 - 0.27 for exhaust, you can look in the parts book to see what sizes new shims come into.

The maths is easy, in the above example, If I make the shim 2.30 instead of 2.35 then the gap becuase 0.05 bigger (from 0.20 - 0.25)

I work out the new shims needed for all the valves.

Then I write down all the shim sizes I currently have that are being replaced and 'match up' ones that I need for other cylinders.

Example, i'm replacing 8 shims in total, for example sake the 8 shims i'm changing are

4 x 2.30
2 x 2.35
2 x 2.40

The 8 sizes I need to make the correct gaps are

4 x 2.30
4 x 2.25

You can already see now that I have 4 x 2.30 in the engine already that i'll be replacing, so I can moev these to the cylinders that neeed the 2.30's. In effect only buying 4 shims instead of 8!

Hope it makes sense.. it's late and i'm sleepy

viewtopic.php?f=24&t=1943

See Gareth's post and you can print a handy sheet out.