When people (which i know alot of you have) home build cossie engines, do they really have to rev them to 3k for twenty mins to run in the new cams?

then still run in for another 1k miles?

So its first ever start up and it needs revving that high?


Carl

 

yes you do.

 

otherwise what happens mate?

 

You knock the cam and / or followers out.

 

you will wear the lobes off the cams,and it will rattle its t*ts off.

 

So re-build. Finish off. Prime pump then fire her up an drev to 3k, constant for 20 mins.. then let off throttle and shut down eat ya tea, then go and run her in for 1k!!

 

This is the case on all engines pretty much.

I tend to just run it for couple of mins at 2500rpm or so to run the cam in though, then run the engine in normally, which involves no more than 3-4K for a fair while anyway.

Never had a problem like that.

Its a nonsense to specify an EXACT rpm you have to do, as the wear in rate of the cam varies with cam profile anyway!

 

it doesnt have to be a exact rpm,2.5 to 3k will be ok.and you probably havnt noticed the wear due to hyd lifters taking up the gap, try it on a solid lifter cam.

 

Ive built more engines on solids than hydraulics mate.

 

ok how many cossy engines on solid lifters have you built?as that is what the post is refering to?

 

chip not trying to diss you, but i think you are giving the wrong advise on this subject.

 

Whats the right advice?

 

revs dont kill and engine when running in,, its load/torque/cylinder pressure

 

Chip is correct IMO. The wear rate and loading on the cam lobe and follower is relative to the rate at which it tries to accelerate the valve which is of course relative to the profile.

A short duration high lift cam will wear at a faster rate than a long duration high lift cam for example.

 

so to simplfy? do you run in the cam for 2 mins or 20 mins?stu?

 

If you look at how my post was worded, I continue to the run the cam in with the engine after the initial 2 mins, I actually run the cam in for a couple of hours effectively.

Its the first 2 mins that are particuarly vital though

 

insert a oil and filter change after the 20 mins.

 

your biggest key is oil changes , new engines cannot have enough oil changes. and dont use fully synthetics, or asda's own, just use a good mineral oil.

i have run engine sin from being brand new to competing on a stage within 150 miles, all sorted and going on to do a lot of hard miles.

 

Yep mineral all the way, I know people who have tried and failed to get rings to bed in on mobil-1 against my good advice

 

do you ever use synthetics ?

i never do, i think its athe biggest waste of money going.

 

i once saw two fireblades baught brand new from the dealers on a saturday,one lad pootles along at 60mph and going down the M6 his mate on the other passes him at 175mph with just under 10 miles on the clock,so my other mate drops it 3 gears,and takes chase,that was them both "run in",both bike went on to do over 20k before sold with zero troubles,and one spent halve its life on the back wheel in 5th at 150mph,i once watch him wheelie it up the M6 for 4 miles at 155mph.

 

I do use synthetics on road cars just cause they seem to last longer before they break down.

On track though im a fan of semi synth because its more affordable and then replace it EVERY outing.


People leave oil in for far too long in trackday cars IMHO, get the swarf out the engine ASAP.


Not really a subject I know a lot about though im afraid mate, whats your preffered oils for different circumstances?

 

The honed finnish when new from the factory isnt the same as when you do a rebuild yourself, and often I believe bike engines are "bench-run" first, so picking up a rebuilt engine for your cossie and thrasing it right from the word go might not be such a good idea.

Im always quite cautious for the first 50 miles on a rebuilt engine, although I then start gradually increasing load from there.

 

to true mate, my ZX12R was showing 180mph on the clock with only 15 miles on it wheni got it !!


we hav enew cars all day at work, the best and most reliable are the courtesy cars - no oil consumption, best on fuel and always the fastest model for model

 

to answer your other ?

i find vauxhall genuine fully synthetic has been the best oil ive ever used.

 

ive tried all the synthetics (wel up to a few years ago as i stopped using them) and always found under heavy use on hydraulic tappet engines to have serious noise after a stage, a decent mineral has never let me down, so if thats what its doing toa set of hydraulic tappets whats it doing to the rest of the motor ?

even on road cars - im a mineral man, unless its specific to the manufacturer for specific reasons, i.e VW group and PD diesel oil is a must.

 

im only cautious for the 1st few miles for leaks and general settling in of ancillery hoses etc.

 

Yeah that and the vauxhall semi are both amazing value for money with tradeclub!

 

you hear quite a few cars coming off trackdays sounding like a 2 bob watch for the same reason, wondering why they are down on power (lack of cam lift) and then half an hour later they work properly again.

amazing what a hammering oil does get when in an engine used HARD

 

i would estimate that the oil in my competition cars gets changed every 150 flat out miles, for the sake on an oil and filter change on an engine its not worth not changing it,

 

are brand new car engines bench run first too?

I work for a car dealership and when we get brand new cars all the chavs working with us thrash the shit out of 0 mile cars.

one of the service advisors told me they don't need running in these days..

 

no they are not mate, and running in is not needed. its all about tolerances these days, mass production on engines is amazing

 

TOTALLY agree

 

ill be in this situation when i finally finish my car, and ive asked this question before but got no answer lol

anyway, so just run the engine for a few mins between 2-3k rpm and check for leaks, if all is ok go for a drive and take it easy, drop oil and filter after 50 miles and continue to drive moderatly for a bit, gradually increasing load and revs.

thats all good and well, but say your engine doesnt have a map for it yet, how do you get round that bit lol?

edit: and what mineral oils are 'decent'?

ill prolly use halfords spec stuff to run in, then what??

 

Thanks for all the input guys. Regarding oil, BMW state i use BMW LL04 oil fully syn, If my memory serves me correctly its 0w30.

The service intervals are quite long and i do hammer the biatch is it worth changing the oil more frequently do you think?


Carl

 

You're going to have a problem then!

You need to be finding a decent base map to run it on.
Massive bore wash on the first startup is NOT good for running the rings in nicely.

From a cams point of view, if you rip the spark plugs out of it (and disconnect injectors of course!), it will turn over at 2800rpm or so I suspect on the starter, so do that for a couple of minutes on a full battery, worst that is going to happen is you fry a shitty zetec starter worth about 3 quid secondhand.



Millers is my idea of decent, they actually do a specific running in oil too, im sure with your legendary blagging skills you can get some cheap, lol

 

Change it halfway through the service schedule every time, so it gets twice the frequency of changes, you'll need to be having the full service history to maintain its resale, so halfway through is only point that makes any sense.

 

good idea about doing it on the starter, will the batt last a few mins tho?

and ive got loads of zetec starters lying around...

shame its on a cossie T5 really

i should be able to get doug to use colins map as a base for mine as his ZT is already up and running, so hopefully the start up stuff should be as near as dammit

cheers chipper

 

Thorough owning there for me forgetting its rwd

 

LOL