1098 Just Done My First Valve Check & Adjustment

Discussion in '848 / 1098 / 1198' started by Boggy, Mar 5, 2018.

  1. Just done my first valve check and adjustment on my 07 plate 1098S at 24k miles. It’s had 2 previously but not by me.

    Lots of patience required and hellishly tedious but not complicated and immensely satisfying.

    Bought a 4V-7mm shim kit from Mike at EMSDUC along with an engine turning tool, digi micrometer, new belts and JPdiag loaded on my PC to tune them at 110Hz.

    Shim kit not cheap but well worth having a wide selection. Despite this, I still needed to lap a few in on sand paper to get the right gaps. But the results were worth it.

    But what a feckin pain in the arse job. You can see why people charge so much for doing it.

    Hopefully a few pics and a table showing the final clearances and shim sizes used.












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  2. welldone Boggy,nice clear pictures,, i just do not have the patience myself so the workshop will get my bike:upyeah:
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  3. All in all, about 30 hrs of my time !!! Can see why people don’t like doing it. Still, I learnt so much doing it.
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  4. Well done mate good effort
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  5. Would be interesting to know Valve clearance readings from previous services over the life of this 1098S?
    #5 quantuman, Mar 5, 2018
    Last edited: Mar 5, 2018
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  6. Thank you so much Boggy for posting your findings in such a methodical way and clear recordings of your findings.. Brilliant!!
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  7. Clearances before I started ranged from 0.009 to 0.022 thou . Must’ve taken the cams out 12 times !
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  8. Gotta make sure they’re not too tight (half thou ok with me) otherwise when things heat up and expand, there’s the potential risk that the valve’s might not seat causing massive loss of compression and power loss.
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  9. Sorry did I misunderstand your chart? are they the end results? I'll edit my post if they are....derrrr...:blush:
  10. Not to mention burnt valves and seats.......
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  11. Yes mate. My chart are the finished values .

    If they’d been that good before I started, it’d have been a couple hrs tops.

    I don’t have the previous values but by my reckoning, I don’t think they probably achieved the clearances I’ve got, not when two of the clearances were 22 thou against a 5-7 thou tolerance.

    Gotta do the quiet clutch mod next to go with a new EVM Z48 clutch conversion. Should be the quietest Duke out there after all this bollox.
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  12. Aye.

    Interestingly, I did a lot of comparison re-using old half rings compared to using new half rings, with the same closing and opening shims, just to chase down the last 0.0005-0.001 inch of gap. Made feck all difference and doesn’t really support the argument that new half rings help to close wide clearances in the valvetrain. I won’t be buying new half rings again.

    The 3 other key things I learnt were:
    1) unhooking the springs to help take the closing shims off REALLY does help and is bloody easy to do as part of the process,
    2) when you rotate the engine to get the piston in the TDC position it is impossible to drop a valve into the cylinder you’re working on. Even with the valves pushed down to rest on the piston crown, the top of the valve stem is still a good inch above the valve seal,
    3) reseating the half rings in their grooves is ESSENTIAL and made really easy by giving the cam followers a ‘ping’ and allowing the spring force to gently ‘tap’ the base of the closing shim to drive it onto the half rings. You do hear a satisfying ‘ding’ when the shim and half rings seat together and bed in. You don’t see this on any of the Youtube videos !

    Defo do it again. So much learnt.
    #12 Boggy, Mar 5, 2018
    Last edited: Mar 5, 2018
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  13. Again useful info by Boggy.. Just to add, I dont think a Desmo engine give half rings such a hard time, compared to engines, with double valve springs...

    Out of interest @Boggy, now your more experienced how many hours will this job take next time? ;)
  14. I am being told that adjusting closer shims is usually a head off job on a testastretta 999.
    Haven't heard this before - any comments?
  15. Looking at the way the EVR basket is machined, I don't think the quiet clutch mod will work with it.

    If you haven't ordered the EVR kit yet, why not just try the quiet mod on your existing set-up?? It doesn't need to cost you anything :)
  16. Interesting. I hope someone clarifies this. Need to do this on mine (998 testa)
  17. Got the EVR already fitted. Have to modify the tangs on a couple of old plates to give a small wavy format to the tangs so each falls into two slots but all looks feasible. Bit of machining to do but nowt I can’t sort. Will post up pics when done.
  18. Yeah. Agreed. Trouble with this job is I have OCD and hunt down the clearances as close as I can. Reckon its still an 8-10 hr job next time ! Pure pain in the arse.
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  19. Haven’t done one yet but I guess access is the biggest issue. Space is very tight.
  20. The quiet mod relies on the slots being machined in a way that leaves a curved end/bottom to them. From the pics I can see, the EVR slots appear to have been machined vertically, giving no curve at the bottom for the tangs/tabs to drop and jam into.