^ interesting post. The reason i like the heads off is that with them on it is possible to rotate the engine a bit too far with tight shims and possibly damage the rocker coating. Better a touch slack than a touch tight. I was told the earlier desmo engines ran without springs for racing and had little compression pressure when turned over slowly as the slacker closing clearances didn't pull the valves fully shut. Once going at speed the inertia and gas pressure closed the valves....
Yeah, that was the same post where I got the advice on how to do the closers. It does seem to make a lot more sense to me and as ducv2 mentions once it's going the compression & spring will nip up what little gap there is. But the important part is "If it was tight anywhere on the cam ". Btw be careful when rubbing on a stone as it's real easy for the shim to end up uneven. The 0.1 & 0.15 clearance was recommended by Tony Brancato and in Ian Falloon's book he mentioned the recommended exhaust gap was increased to 0.2 as it was prone to burning when run for prolonged periods without checks/adjustment. But it sounds like you have done your research and know exactly what you are doing. There always does seem this fear of doing the (bevel) valves but you just need lots of time, patience & of course shims Yep, they do very much look like the internal seal guides as there is no grooved lip on them for the green/black external push on types to seat/grip onto. You will have to take the heads off if you want to replace the o rings as it's a tricky job getting them in. I managed to do it by holding the valve in the guide from below with the top of the stem just below the groove, dropping the o ring in and then seating it home with a suitably small plastic or wooden pick from above. You then need to push the valve pass the seal without it's collet groove putting a nick in the seal on the way past. If there's no oil burning I would be very tempted to leave it as is plus you don't want to be opening another can of worms and getting the guides replaced. But that is another story you don't really want to get involved in if you don't have to And here's my highly technical piece of equipment for supporting the cylinder head when off the bike. Note the arrow to remind me which way the bevel turns.
Fresh rubber smell down in the garage! I am not used to these tire sizes. It looks really antique to me… I find this very cool, to be honest. I also corrected the rear sprocket assembly to a more OEM looking set-up.
I'd be interested to know what sort of pressures you settle on after a few test rides. For me, with ContiClassic Attacks, it didn't feel comfortable until the rear was reduced to 2.2 & the front to 1.8
I got some advice to increase the front to 2.8 if need be, as these tires sometimes generate some sort of « drifting » in the front. Not sure about the word. Nothing like tire skidding, more like inaccurate trajectories.
Engine cleaning making progress. It’s a slow and tedious process, rubbing with steel wool after degreasing, but it certainly starts to show.
Yes. See also: handles 'like it's on roller skates'. Or if worse than that 'like a pig on roller skates'. And if worse than that 'like a pissed pig on roller skates' ...
I found on the Darmah, the higher tyre pressures, especially on the front, made the bike feel 'skittish/nervous' and not at all planted but am unsure whether that is due to the tyres, the bike or my ability However things may well be different on your SSD with the dropped bars, raised foot rests & fairing putting more weight onto the front end.
I am facing a new challenge here… Is there a known trick to remove the stator from the cover, once the 4 screws and retainers are off? It won’t budge a millileter when I try to manually pull it out. It’s pretty much stuck in its housing and franckly, I hesitate to use mechanical force with some sort of pulling tool for this. I really don’t want to damage the stator…
The fall leading to the damage that needed a repair may have shaken the fit between the stator and the cover. I found some info about the fit being fairly tight anyways, so I decided to try and gently pry it out using a small wood block at the bottom with a bent tool and a thin flat screwdriver to free the stuck sides. Felt absolutely nothing at first, so I kept going gently around and around and after a while, I saw it starting to come up very slowly. 10 minutes later, it was out, unmolested, and easily transplanted to the new cover. Only the O-ring didn’t make it, so had to order a new one from back to classics (I have a pending order there for other parts anyways). so… Success!
I started working the valve clearances on the horizontal cylinder. Openers shims are very small! 2.30 and 2.15… And I need smaller to increase the clearances to 0.10 (intake) and 0.15 (exhaust). My D2 shim kit doesn’t go below 3.00, which means new opening shims need to be ordered… Damn! Closers are more in line with my kit, around 6.80.
Just measured 2.00 and 2.15 closers on the vertical. So that appears to be the norm for these engines ?
I'm not entirely sure you can ever apply the term 'norm' to these old bevel heads. Remember these engines were built using 1970s production techniques & tolerances - that's why it's full of shims As an example my openers (oops edited) are 3.48, 2.27, 3.31 & 4.03
My shims were all over the place as well, in contrast when I did the shims on a Panigale, all of the closer shims were exactly the same size as were the openers. Just changing the closer shim collets put the clearance right into spec. 50 years of progress I guess. How are you doing with the closer clearances...
