Things to do with the motor while its out

[Mananon]

Oooh, messy Cammo. Don't envy you that one mate.
Still, if you're putting it back together you can look at doing every mod there is, ground up style.
Also, seeing as you have the chance to see everything inside, I take it there are backlash gears down to the crank?
Obviously the easy mod it to take off just the cam gears as they are easy to get to but, can't you take them all off? I think I've read about this somewhere and it's got to be worth doing if the case is already open.
This is my first V4 so I'm learning as I go here and therefore a bit hesitant to open the cases myself.
Mind you, this rebuild started with me taking the plastics off to get them repaired, then the undertray to clean it, then the subframe.....now I've got the cams out! where do you stop? I keep thinking "well, I've gone this far so, just a bit more won't hurt."
Been through this before with other bikes. The trouble is I enjoy it too much.

Still no pointers at how much to skim off the head. I can find referances by doing searches but the figure varies wildly. 0.2 to 0.7mm, the latter sounds way over the top to me.

I've been thinking about the shimming required after skimming and how this would work if the backlash gears are removed. Now, if you were designing a gear drive that was never intended to have backlash compensators you'de make it pretty tight. However, with the lash gears, you wouldn't need to. You could run open tollerances and the lash gears take up the slack. So, remove the lash gears and you've got a sloppy and therefore noisy set of gears.
What I'm thinking is that with the quietening gears gone, you might want to tighten things up a tad to keep the noise down (if you wanted to). Make sense? The clever thing here would be knowing how much to tighten it up by.

Just out of interest Cam, how big a job is splitting the cases?

[Neosophist]

Looks good.

You can get a valve lapping stick / paste from Halfords for about £4.50, i brought one last week

Valves look in good knick too from what I can see.

[Drunkn Munky]

Still no pointers at how much to skim off the head. I can find referances by doing searches but the figure varies wildly. 0.2 to 0.7mm, the latter sounds way over the top to me.

You could make a cheeky phone call to a tunner, RLR, BMC, Dynopro and get the info, you never know they might just tell you.

Seeing as your making a proper job of this, RLR drill out the spark plugs holes and fit larger plugs, bigger spark = bigger bang i guess could be worth looking in to.

[Neosophist]

Still no pointers at how much to skim off the head. I can find referances by doing searches but the figure varies wildly. 0.2 to 0.7mm, the latter sounds way over the top to me.

You could make a cheeky phone call to a tunner, RLR, BMC, Dynopro and get the info, you never know they might just tell you.

Seeing as your making a proper job of this, RLR drill out the spark plugs holes and fit larger plugs, bigger spark = bigger bang i guess could be worth looking in to.

Isn't this due to cost?

You could always fit 24 heads if you wanted 10mm plugs, they can be had cheap enough on ebay, if you get one with the rockers in it you wont' need to mess about with all your shims after either as they use locknut adjusters... great for when you lap in valves etc :)

You could skim it 0.5mm and see where your at and go from there.

[Mananon]

Now that sounds like an idea Neo.
Trouble is I'm back to ordering gear off ebay that'll take another month to come.
If I could find a breaker that had them here I'd be paying a couple of hundred quid.
Other than lock-nut adjusters, are they the same as 30 heads in all other regards Neo?
Cheers,

[Mananon]

Lapping the valves today.
Anyone know the correct valve and seat seal width? I'd guess it'll be something like 1.5mm inlet, 2mm outlet maximums.
If I can get the specs to do this spot-on I'll post a 'How to" thing if anyones interested?

[Malc]

If you are skimming the heads, 0.008 inches (0.2 mm) max is enough, and you'll need to source some shims for the cam carriers, etc. As it happens, I have a rather neat little drawing of said shims, but you'll need washers for under the cam drive assemblies not shown on this drawing, they are easy enough to work out whats required. The thickness of the material to make them from should match how much you skim off...

[Malc]

Lapping the valves today.
Anyone know the correct valve and seat seal width? I'd guess it'll be something like 1.5mm inlet, 2mm outlet maximums.
If I can get the specs to do this spot-on I'll post a 'How to" thing if anyones interested?

The valve seat, according to Haynes, is 2.0mm all round.

[Mananon]

That's great Malc. Thanks very much.
Is the 2mm both inlet and outlet valves mate? I've ordered a Haynes from Aussie but it's not here yet, They're usually a bit different. Visually the inlet valves do appear to have a narrower mating surface.
I'll get those shims made up at work this week.
Any idea what that does to the compression ratio, power output and if there are any adverse knock-on effects?
Last thing, and I'm assuming you've done this, I'll need thicker tappet shims. Are they hard to get? Davis Silvers site says they can get them but doesn't say if they can size to order. Nowhere in NZ stocks these and they charge a mint (admin charges they call it) to order any parts.
Thanks again Malc.
Duncan

[Cammo]

Dunc, the haynes has the inlet and exhaust seat width at a specification of 1.70 - 2.30mm, so Malc is correct in saying 2mm all round.

Hope that helps.