Oiling before starting every time

There is a lot of stories, and mechanics, who said from ages that blipping a cold engine is not the best thing to do. BUT, as usual, everything is about compromise. Here, blipping a cold engine is good for the cam. And history learned us that, specially with vertical engines*, blipping a cold engine is bad mostly for barrels, pistons and rings. Knowing this, we can now chose which parts we would like to change first. Cam or pistons and rings.

BTW what do you think about an easy kicking, without the plugs, if the bike was not used for, let's say a week or two? Would it be enough for a cam oiling, thanks to wet sump?


* Why do you think flat engines, like Cox, Porsche, Subaru, 2CV, Goldwings and Beemers are so reliable?

I use a pit roller starter for my race bike, spin it over a few times with the kill switch off before I start it for the first start of a race weekend . Oil is Driven 15W50 Synthetic (Joe Gibbs)
Carbs are set to 1500 rpm aprox. and I blip the throttle up to 3500 while warming up
No negligible cam and or follower wear after 5 seasons of racing.
Regards Mike

No controversy on best start up practice just ignorance of facts to treat engines as if a tender mommy nursing her child. Cam contacts are the main thing that needs oil wedge but before that happens surfaces passing each other rather quickly have less drag and galling than slower wiping does. Ring seating is best done with dry polishing compound or just dry. TotalSeal Rings knows this and sells their version of Bon Ami power for new rings but also know many men's motherly instincts recoil at this, so say if they must - can spritz with WD40, hehe because that will flash off to dry on first ignition spark. Lots of tales of expensive race engines being finished too close to race start to break in so just rage into racing to find great ring sealing afterwards. We all know bad juju to rev below 2000ish on new cam and lifters - so should all starts. Tested this on Trixie Combat after piston fracture messed up lifter and cam surface so had comnoz resurface lifters and I used file to clean up cam. After 6000-ish miles began smoking more and more from wet sump so split cases to clear internal passage of swarf taken in while passage expanded hot but cool trapped the metal chips. Lifters distinctly better polished than comnoz supplied and cam lobes glass smooth even bands. I've half dozen new rebuild starts watching how long before oil returns to tank and how long for head pressure to hit at over 2000 rpm, 30ish sec oil gauge on head lifted needle and about 15 sec later foamy oil return and about a min more for just oil w/o much air returned. Not redlined on break in and afterwards starts but too soon too slow idle not best practice, unless pre oiler supply before pump charges up. If I'm in a hurry, I just wait long enough blipping til good throttle response then head out in low gears to keep 2000+ rpm going til decently warm and fuzzy all over. I'm sure there are engines that need fully warmed for various clearances to stabilize before loading for real use but ordinary Nortons are not that kind.

What about post-oiling? Many old aircraft engines had shut-down procedures that were just as involved as start-up, if not more. If oil could be circulated throughout the system AFTER a good, hot run....... Motorcycle drag racing engines can not be shut down immediately after a run or the oil in the head boils off, stems seize to guides etc.

Does not apply to Norton air cools, only heat soaked engines retaining oil in turbo's or other areas that would cook if not moved along till cool enough to rest. Shoot may even be more to protect large engines from heat shock distortions if not spreading the coolling more evenly. Keep in mind most mention on oil temps mainly concerns cooling the oil back down more than thoughts of cooling bulk of engine. Thin layers and thin passages are where temp transfer matters most. Too overwhelmed to get much Commando progress so this is closest I get lately beside a still silent oil-less one in living room. Hehe wife told me 1st time its oiled is last time inside, so how's that for ambivalance.

Too much worrying!. Start 'em up, ride/drive 'em off!

MexicoMike said:

Too much worrying!. Start 'em up, ride/drive 'em off!

Click to expand...

Nuff said.

Terry Prince came up with this neat little collection galley and drain for automatic cam pre-oiling. After shut down the oil in the timing chest drips down for quite awhile.
Each cam follower collects a quantity of oil then drips the oil directly onto the cam for the next startup.
Different cam/follower arrangement than the Commando but perhaps the idea could be adapted?
Glen

I have occasionally got myself well oiled at the bar before starting bike, but I'm older and wiser now.

Ken

MexicoMike said:

Too much worrying!. Start 'em up, ride/drive 'em off!

Click to expand...

Yes, Commandos may be old, but they're not Edwardian!

Its worth while to lighten Norton lifters drilling most of slab part out and make small drain holes to drain on lobes and slightly lower the oil puddle inertia to boot. I also ground the oil drain bevels a bit bigger but can't claim a good idea or not.

You say you want the followers to "surf". Does flooding the cams allow the surfaces to lubricate properly? Do they need speed as well as oil?
By the way, I think preoiling useful but only when the bike is fired up first time you go out and of course after it has sat for days or weeks.

Onder said:

You say you want the followers to "surf". Do they need speed as well as oil? Does flooding the cams allow the surfaces to lubricate properly?

Click to expand...

Technically, it's known as "hydroplaning", and it has to happen with every plain bearing (rods, cam, tappets, rockers, you get the idea) since they can't tolerate any metal-to-metal contact. Rod and cam bearings have it much easier than the tappets, since they have relatively huge surface areas, and their very design helps to retain a quantity of oil after shutdown. Tappets, on the other hand, have a razor-thin contact area, and, if the engine stops with the valve open at all, there's spring pressure squeezing out the oil from the contact area. As noted numerous times in this and other threads, the cam must be moving at a good speed to keep that oil film wedged between the lobe and tappet. Keep in mind that the cam is only turning half-speed of the crank.

They don't really need to be flooded, but they do require a constant flow of oil, as the wiping action is removing the oil film every time the valve is opened. Most of the overhead cam engines I work on have a reservoir built around the cam lobes which holds a puddle of oil for the next cold startup.

Onder said:

By the way, I think pre-oiling useful but only when the bike is fired up first time you go out and of course after it has sat for days or weeks.

Click to expand...

Assuming you've packed everything with assembly lube and the oil tank is full, you shouldn't have to pre-oil after a rebuild. If you have the means to do so without spinning the crank, then by all means do so. Just don't try to pre-oil using the kickstarter or e-start. With the current oils out there, synthetics in particular, their clinging tendencies are such that this isn't as much of a concern as it was in the past, assuming we're talking about an already run-in engine. As Smokey Yunick said when asked a similar question, "Once you see the oil pressure light go out, drive it. Don't hot rod it until it's up to temp, but don't let it sit and idle" 'Nuff said...

Nathan

Ugh, Tribology study long ago established that dry metal contacts rubbed slowly under pressure causes most friction and wear. A layer of lube be it dry powder, water or oil helps keep a molecule or more thick separation on slowish sliding surfaces, reducing friction/wear but still allows hi spots to snag/gall/heat - until enough speed/pressure developed for lift off on oil wedge. So yes a good splash of oil definitely better than dry lobes but there is not full separation till over 2000ish in most cases. So limit time as practical - below cam wear-oil flow thresholds is all.

AMC sleeve bushes/shafts are another example of lack of oil not fully separating - preserved mainly by speed of surfaces as ONLY time oil ever gets above to drain onto/into area is while 4th gear riding and even then not much as oil supply has to enter thin bush/shaft/cog spaces that are spin flinging most oil outward.

In winter cold oil flows slower so this thread lingering longer than if spring time.

I've often wondered about mainly DOHC bike engines where their is no centre stand and the bike lives on it's side stand. Any oil pooling in the cam journals is more likely to drain away. Not much of an issue on a Commando

New fangled OHC valve trains use pucks between stem and cam lobes and get similar to less mileage than decent Commando's. The smaller hot dirt bikes and quads go like stink for a couple seasons then pucks worn out and young people have to abandon them at shop d/t the cost if someone don't rescue. SV650 manual expects 30K m before major surgery to carry on.

Norton twins just before Commando had cam oil bath tub great solution. ludwig showed foresight and extra handyness creating his own. Prior to Commando a good lot of cycles were daily transport so start stops starts piled up to notice = then cheap cars and small japan cycles hit so Brit Iron evolved to thrill us boys till next faster model for sale.

ZDDP works by depositing zinc nano pads faster than wiped off. Only happens if oil above boiling temps and hot surfaces, moving fast enough to wedge/surf off surface contact to allow layer to build up to protect on shut down, momentary oil pressure lost, such as long air borne cycles or gymkanna switchbacks and next start up. Does not take long - many slow rpm revolutions to wipe em off. Kind of sliding scale of equilibriums and too much is as bad as not enough. 2000ish ppm for break in, 1000ish after.

hehe theres a few moderns that should not wheelie long or oil pump sump sucks air till seized.

Pre-oiler can also be an accumulator. Systems used in auto racing and a backup hydraulic system in modern helicopters. Problem on any Norton is space.

well everyone like MexMichael and myself included pretty much talked pre oiler out of the picture but was fun thought while lasted. Best I know to do is use decent ZDDP oil and much as possible go straight to cam surf rpm before the ZDDP gets wiped off and try to get full heated engine to re-deposit ZDDP before shut down with minimal idle time. None the less Commando idle is so addictive i generally Scarface some Commando life for my gearheaded pleasure. There have been very few time felt as close to heaven as when late Wesley took me to a big rally to hear the pleasant pitter pats through wooded area for 3D gut sense of their presence.

ONLY area that really needs pre-oiling is the AMC sleeve bushes, ugh.

As Herb Becker said to me re my concern over my existing but new +.080" 650 ss pistons& bores -
"You'll never wear it out"

Glen

Ah so worn&torn glen its you and Herb's sort of physco therapy I seek here.

Btw I highly suspect a significant part late Ms Peel's freaking run out from under performance had a lot to do with lower friction of both cyro tempering and Titanium Oxide Dry Friction impregnation.

On an oppositional subject note, like Wesley would throw up out the blue at stops, if ya ever a gallon of gas away from civilization, discovering significant oil loss - how much further dare ya go if only 1/4 oil tank remaining before seizure or calling rescue? If cold front hail & night fall approaching? Thankgoodness Commandos sound pleasant and look cool so farmers more interested to assist than shoo off with shot gun.