Flushing engine oil

[SlashWylde]

Hi folks, it's time for an oil change in my bike and I was thinking of dumping out the old oil; re-filling with some budget non-friction modified car oil and then running the engine for a few minutes; dumping again and repeating till the oil stays clean when dumping.

After this process is complete I would then refill with my normal good quality bike oil.

My question is, is this a bad idea? and if it's a good idea can anyone suggest some suitable brands/sources of cheap non-friction modified car oil?

Would greatly appreciate your advice.

Thanks,

-SW

[Bonez]

Why? I've owed the same two bikes for 20 years. Just change the oil/filter and removed the oil pan/sump every now and again, once every 5 years or so to check the strainer and remove gung thats built up.

[Troll]

is the oil that filthy??

if it is relatively clean just change it and the filter and stop worrying

check out some oil suoppliers and buy a 25 / 50 litre drum of oil if you want to save money

also car oil filters often fit

my bike has been around the clock and bottom end has not been touched and it just get regular oil changes

[Motu]

Flushing would be an absolute waste of time on a 2005 bike.With an old clunker like that you'd be better off stripping the motor down and give it a really good clean down...solvent bath,then a wipe out internaly with lint free rags.How did you let it get into such a state?

[notme]

Flushing would be an absolute waste of time on a 2005 bike.With an old clunker like that you'd be better off stripping the motor down and give it a really good clean down...solvent bath,then a wipe out internaly with lint free rags.How did you let it get into such a state?

Motu, serious question - wouldn't it be arguably of more value doing what SW suggests on a 2005 bike than say my 2003 bike due to all the crap (factory coatings, swarf, break-in junk etc) coming off the new engine only a few thousand k's after it's run in?

Your expert advice appreciated please......

[Shadows]

Well, taking care of your bike has just gone to a whole new level!
I'm no expert but I can't see anything wrong with that. Good siht. Shame you can't prove that when you go to sell it but if you look after the rest of the bike that way it should be plain to see.

[nadroj]

Synthetic or semi syn will clean up the insides as new.

[Bonez]

Motu, serious question - wouldn't it be arguably of more value doing what SW suggests on a 2005 bike than say my 2003 bike due to all the crap (factory coatings, swarf, break-in junk etc) coming off the new engine only a few thousand k's after it's run in?

Your expert advice appreciated please......

What you mean not every m/c manufacture runs in their m/cs like Lifen does?

[scumdog]

Dump oil and filter,put on new filter and run it with a 50-50 ATF and 10/40 oil, run it for 15 minutes then dump oil and filter.
ATF is highly detergent.

Or you could pull the spark-plugs after dumping the oil and filter, spin engine over on starter to purge any excess old oil then do normal oil/filter replacement -I've done it that way on all sorts of engines for years.

[Pixie]

I changed my oil at 200 km,not wanting to go 1000 km to the 1st service with manufacturing crud circulating.
The oil I drained out was sparkly with metal bits.I replaced the oil with cheap Repco 20W40 and at the 1000 km service,the mechanic said he could tell someone had already done an oil change.

[2much]

Just put some engine flush in there, run it to warm, then dump the old oil out.

If you usually run synthetic oil, I wouldn't recommend using some cheap mineral oil to flush it as it's a bad idea to mix synthetic and mineral oil. (don't ask me why exactly, I can't remember right know. Perhaps one of the mechanics here know)

[jonbuoy]

I was told not to flush with flushing oil, you can dislodge crud that could work its way into a small oilway and block it instead of minding its own buisness where it is. I think also its best to stick to one type of oil and not mix them up too much. Some oils don't like mixing and can foam up/cause clutch problems if its a wet one. If your really worried just change it again after a couple o thousand k's. my 2c

[GSVR]

Ive just done a couple of hundred ks with Delo 400 which is a diesel oil. Was pretty dirty when I drained the sump so must have done the job.


Its a bad idea to mix mineral and synthetic oils? Whats a synthetic blend?

[Bonez]

Ive just done a couple of hundred ks with Delo 400 which is a diesel oil. Was pretty dirty when I drained the sump so must have done the job.


Its a bad idea to mix mineral and synthetic oils? Whats a synthetic blend?

Stumbled on this - http://www.trustmymechanic.com/motoroil.html

Download the pdf. There is an interesting section relating the m/c oils.

[Grinner]

Its a bad idea to mix mineral and synthetic oils? Whats a synthetic blend?

Oils are made up of base stock and additives. ( 10 to 30 % ) Generally, the reference to synthetic oil for an engine, means a lubricant is formulated with a polyalphaolefin (PAO) base oil.

However, because the PAO base oil does not dissolve additives effectively, it is usually formulated with an ester co-base (usually di-ester and/or polyol ester). The additives are soluble with the ester and the ester is soluble with the PAO.

Likewise, the PAO tends to cause seal shrinkage and the ester causes seal swelling, so the effects are offset when both base oils are present.

It is the ester that can cause problems when one changes from mineral to synthetic. Ester base oil used alongside PAO base oil in oils has excellent natural detergency. In other words, it will clean up varnish on component surfaces as a result of thermal and oxidative degradation of the lubricant. When one switches from a typical mineral-based engine oil to a typical synthetic-based oil, the varnish layer will be removed by the ester in the synthetic oil and become suspended.

This suspended material can rapidly clog filters and can block oil flow passageways and lead to component starvation.

If your machine has been operating fine using mineral oil don't change. If you do swap over to a synthetic try to clean the system before making the change.

Happy riding.