Continuing Saga of Oil Burning Bandit

[2005B12S]

http://mototuneusa.com/break_in_secrets.htm



I came across this a while back, it makes perfect sense. Engines are run in on the dyno all the time. You have a very limited amount of time to get the rings to seat fully before everything goes smooth- once that happens they are either properly seated or not.

I believe the manafacturer's break in guidelines are way too conserative. The biggest factor is to have the bike fully warmed up before running it hard. Cold oil does not provide much lubrication, here is where most abnormal wear occurs.

The only thing that really caught my eye was the 1800 mile interval before the first oil change. That is extreme, on a fresh motor I will change oil at 50, 250, 500, and 1000 miles. Oil is cheap compared to the cost of the motor itself. You are removing all the assembly lube and metal out of the oil as the engine wears in. This is  more important than following manafacture guidelines on when to exceed certain rpm's.

I am putting an 816cc kit in my GS750ED. The app. costs are:

Piston Kit w/rings and head gasket          $475
Cylinder boring/machine work                $250
Engine gaskets misc                              $100


I do my own work, if paying for labor expect $400-$600.

[broncbob]

this is gonna sound wrong but the best way to seat the rings in a air cooled vw is to install dry and fire her up and give it a few good whacks on the gas and poof seated rings! not sure why this works, mabey the opposed cylinder thing but was told to do it by a long time vw wrench and it works like a dream! so the thought of breaking a engine in on the dyno doesn't bother me, it may not lead to the longest engine life but if you need to know how much power your getting that soon in the game my guess is that long life is not in the cards!

[Bazza]

http://mototuneusa.com/break_in_secrets.htm



I came across this a while back, it makes perfect sense. Engines are run in on the dyno all the time. You have a very limited amount of time to get the rings to seat fully before everything goes smooth- once that happens they are either properly seated or not.

I believe the manafacturer's break in guidelines are way too conserative. The biggest factor is to have the bike fully warmed up before running it hard. Cold oil does not provide much lubrication, here is where most abnormal wear occurs.

The only thing that really caught my eye was the 1800 mile interval before the first oil change. That is extreme, on a fresh motor I will change oil at 50, 250, 500, and 1000 miles. Oil is cheap compared to the cost of the motor itself. You are removing all the assembly lube and metal out of the oil as the engine wears in. This is  more important than following manafacture guidelines on when to exceed certain rpm's.

I am putting an 816cc kit in my GS750ED. The app. costs are:

Piston Kit w/rings and head gasket          $475
Cylinder boring/machine work                $250
Engine gaskets misc                              $100


I do my own work, if paying for labor expect $400-$600.

I would like to add my 2 cent's here. Yes, it is true most engine damage is done at start-up, but not from cold oil. The damage is done from lack of circulation of oil at start-up.

Remember there is more to breaking in a new engine than seating rings. On a new engine you also have new main & connecting rod bearings, Piston wrist pin bearings that sometime have very tight tollerances. This is of course even more exagerated on a cold engine.

[Red01]

True, but rings are the only things that have to seat, or 'break in.' The tight tolerances on all the other parts are supposed to stay as tight as the assembly specs for many thousands of miles. I once tore down a Honda Civic motor to rebuild the head and figured I'd go ahead and throw fresh rings and bearings in it while I was at it. The motor had 188,000 miles on it and the bearings were still within factory "new" tolerances. Since the mains cost $30 per journal and the rods were $26, I decided to leave them alone. The engine was still running fine when I sold the car at 325K.

[CWO4GUNNER]

I concur that I also believe this is true. I learned working with naval engineers while in the service that this is the very reason why most main propulsion and auxiliary engines in the marine industry have pre-circulation oil pumps which are activated prior to engine start up because marine engines have to last and do last more then twice the hours of engines without them.

http://mototuneusa.com/break_in_secrets.htm
I would like to add my 2 cent's here. Yes, it is true most engine damage is done at start-up, but not from cold oil. The damage is done from lack of circulation of oil at start-up.

[BanditAllan]

As I understand it the oil holes were wrongly designed so oil passed above the rings and entered the combustion chamber.
Since the engines were over oiled in this condition unless it ran low on oil the bores should still be in good condition.
Therefore to solve the issue using a set of pre 2001 pistons and rings with a gasket set should be all you need in parts to solve the oil burning issue.
A simple bore diameter/runout check and light cylinder hone should be all the barrel needs as well.

[China Greg]

Wow, I'm going to see if I can re-open this cob-webbed thread again... [tap tap].. anyone OUT there??

I've got a 1st Gen B12 now with 130K on it.. (about 20K since a total motor overhaul, including all new bearings, JE pistons, rings, valve seals, etc etc.)

It's going through a lot of oil, presently... maybe a quart in 750-1000 miles. Funny thing is that it doesn't SHOW any SIGNS of burning oil...such as smoke at start-up or oil in the pipe end. The bike runs better than it ever has...crisp, strong (120 hp / 84 lbs torque on Ivan's dyno), and smoother than anyone else's B12 (I balanced the clutch basket and crank).

But it's simply using oil. Maybe extra crankcase pressure is forcing oil into the airbox...this has been suggested. It has also been suggested that, if the plugs are clean (they are) and there's no signs of malfunction... "F"-it... just ride the som-bich.

[BanditAllan]

Did you consider the possibility of worn exhaust valve guides or seals that may be leaking oil into the exhaust ports. The quantity you mention is not really enough in the mileage quoted to have a visual effect with smoke showing out the exhaust.
Pull the header off and have a look in the exhaust ports, better yet if you can see the neck of any exhaust valves for oil accumulated residue sitting on them  It will look like hard scaly carbon build up.

[China Greg]

Thanks Allan, those are great suggestions.
The head I'm currently using was from a 2002 donor motor, with 20K on it. Before installing this one I had a local engineer (race car level) clean the valve seats.. and I installed new seals.

Hmm... I'm wondering what seals I put in... I don't THINK they were OEM Suzuki... (they definitely were Viton, and I did an inspection on them)...

So I supoose it's possible they were not the highest quality. Can't know for sure... but you may be correct about the ways to check for that. I may want to put an aftermarket header on it this winter... so I should have a chance to see the valve stems.

[BanditAllan]

Worth some inverstigation for sure, so when you can get around to it let me know your findings.