First Questions - Camel

[Butch]

Posted my intro elsewhere just yesterday. I have a manual for the bike though it seems to be more generically for the roadsters, but no matter. I'm going to want to give the bike a good once over and service before I go far on it.

I'll change the cam belt whilst I'm about it. I see I need a special tool to get to it. Is that something that I can make or am I going to have to splash some cash?

I note that I need a specific cam belt according to a letter inscribed on one of the pulleys. Really? Can I see that before reaching for the special tool?

I don't want to turn this into another oil thread, but I note that 20/50 is recommended on these engines - and that they don't have a proper oil filter. I'm thinking the engine runs solid lifters - so any 20/50 with a high ZDDP content should do, right?

[MickeyMoto]

Hi,

Nlm do a graded belt if you want one. I buy a good quality belt for a fiver (ish) and change it once a year (when the bike is on the road).....

I use Halfrauds 10/40 semi synthetic, often on special...

Service Saturday morning, ride in the afternoon.....

[Ming]

You do need a flywheel puller - but they're not expensive and are the same as most scooters. If you have an air gun it's easy to rattle-off the nut (apparently), if not you probably need to make a sort of peg spanner to locate in the flywheel holes. Belts are expensive from NLM (in my opinion) as they still grade them. Most modern belts are cheap enough to buy a couple and choose the best fit - look at the moriniclub.nl site for lots more info on belts (and other stuff). EVGuru (Paul Compton) has a good series on youtube covering belt changes - well worth a look for your first go.

['It must be a .....']

Hi,
A cam belt from RS Components is <£5.00 including postage: Contitech (Continental) Size 124L075, Part No 474-9793
High ZDDP oil - Valvoline VR1 20w50
Comma do an oil with higher ZDDP content but can't recall the name.

Hope this helps, enjoy!

[EVguru]

No need for a high Zinc oil.

All the horror stories about flat tappet engines having problems with low Zinc oil are based on American V8s with 2" inlet valves and springs heavy enough to control them. Even in very worn out Morini engines, I've never seen a follower with significant wear on the face.

[harrymuffin]

Comparing the Morini engine to American engines, the valve gear is, without doing the calculations, under more stress in the Morini engine owing to inertia; the load on the valve gear increases exponentially as speed rises and as the Morini normally runs in the 4500-8000 rev band and the American V8 in the 1500-5000 rev band the loads would probably be the same if not higher. The other problem with the Morini engine is the rockers which do not have replaceable bearings; the alloy steel rockers run direct on the shafts, so additional lubricatious ingredients would be beneficial.
If you do have pitting on the cam followers then you grind them with grinding paste on a piece of plate glass, not ideal as the cam followers should be slightly convex to aid rotation, but it works. I have along with the two Morinis, one a 507cc 350 and a 496cc sport, have three other 'historic/classic cars, one of which has very high valve loading owing to its convoluted valve arrangements where the cam followers are £35 each and there are 12 of them. I use Valvoline VR1 20-60and change the oil every 3000 miles or 2 years. The other two cars the cam followers are a bit cheaper at £2.50 and so use Morris oils Classic which also has a high zinc and phosphorous content and would be happy to use this in the Morini which have VR1 20-50. You could get away with a genuine oil for diesels as these still have reasonably high zinc additives, but without going onto the manufacturers web sites then I would use Valvoline/Morris or Mobil which is too expensive for me. There are other high zinc oils around but not in the 1200+pp amounts that were once common.
As an aside, before I had studied tribology, probably not high on the courses undertaken by electricians, I could not afford decent oil for my OHC Velo and had to put some Woolworths 5/- a gallon oil to go to the T.T. I just about got home as the power was getting less and less so much so my top speed arriving back in Birmingham was not much more than 35mph. On taking the head off and inspecting the camshaft there were no lobes to speak of, yet the pads on the rockers were perfect because they are stellited.

[EVguru]

Comparing the Morini engine to American engines, the valve gear is, without doing the calculations, under more stress in the Morini engine owing to inertia

I've not done calculations either, but the valves are very small and light and the rocker ratio is no more than 1.35 to 1. With a little determination you can remove the valve spring caps by hand.
I'll repeat, I've never seen significant follower wear, or indeed cam wear. Usually you can see your face in the cam follower and a lot of the time there is still some of the black oxide finish visible on the lobe flanks. This is even on the 500 engines where the cam base circle was reduced from 20mm to 17.5mm.

The other problem with the Morini engine is the rockers which do not have replaceable bearings; the alloy steel rockers run direct on the shafts, so additional lubricatious ingredients would be beneficial.

I've replaced many sets of these non existent bushes, in fact I made a video of doing so. The original bi-metal bushes are not available, so I use a Bronze/Lead/PTFE bush.
Intermittent use and short trips seem to be the enemy here because of the mist lubrication system. I often see less wear on high mileage bikes.

[harrymuffin]

I must beg your pardon regarding rocker bushes, I have just popped out to my store cash and yes bushes are fitted to the rockers, I have never had to replace one, though I cannot think for the life of me why anyone would need to make a film of how to replace them, even a half wit should be able to work out how to press out and press in these bushes.
I also checked the cam followers I have in store - fifteen of them but don't ask my why the odd number - and all have pitting on their faces accept one and the camshafts (5) mainly sport and a couple of 500s are all serviceable, probably because they were in use when lubricating oils had high concentrations of zinc and phosphorous.
Whether you can or cannot remove the collets with your fingers is neither here or there, what matters is the poundage the springs exert when the cam is fully open and the rate this load increases as it opens and the speed at which it opens! I cannot be bothered at this time to undertake to measure the spring rates that Morini fitted to the engines, but bear in mind that the cams open at different rates and have different lifts so that the load on a sport cam fully open would be different to the load on a strada cam.
Better to air on the side of caution and use an oil that was similar to the oils when these engine were designed, than the current oils that are blended for engines with catalytic converters with different cam trains designed to cope with low levels of ZDDP.

[72degrees]

Coo! The Mother of All Oil Threads brewing.
<Opens popcorn>

[MickeyMoto]

Nah, too technical. It breaks I replace or find somebody to fix. I can bolt things together but have trouble with metalwork.

I use oil, it lubricates. Better than no oil.

[SupermotoDave]

Cam follower wear or camshaft wear is not a problem I recall coming across before and the 350 engine has been around for over 40 years, I don't think I'm going to worry and will stick with 10/40 semi synth.

[Steve Brown]

I've never seen cam or tappet wear in a Morini engine either. I'd guess too that American V8s are hardly worth comparing them with? Different kettles of fish etc. As for 'how to' videos, they are there for good reasons too. I've watched plenty and found them variously helpful and dangerously useless too. Point is, they're there because someone thought it useful to show others something less easy to explain verbally and to avoid having to repeat it over and over. They are popular too, so if you find you don't need them, be happy you're so clever!

A happy half-wit, yesterday.

[EVguru]

The oil recommended by Morini in later handbooks is Sint AGIP 2000, which is a 10w40 semi synthetic.

Zinc compounds are added as anti-scuffing agents. In the event of the oil film breaking down and direct metal to metal contact occurring, they're designed to prevent galling between the two surfaces.

The oil film is not supposed to break down, but the oil may be beyond it's recommended service life, contaminated with water from frequent short trips, or simply be too hot. That's assuming enough of it is getting to the right places in the first place.

Castor oil still provides the ultimate in film strength, and Castrol R40 for example contains no Zinc. Synthetic oil bases also have a higher film strength than traditional mineral oils and even in a blend give more protection.

The Morini engine has little or no reported history of cam or follower problems, so I don't see a real need need to recommend seeking out special oils that cost a significant amount more, or are less readily available.

Cheap supermarket multigrades are probably best avoided. They often use a low grade base oil and then a lot of additives to meet the multigrade spec. Rolling bearings and gearboxes degrade the additive package quite fast.