03-10-1999
Here is an advise from a German driver Christian
Hosch for breaking-inn OS engines.
Put the car on the starterbox and start the engine. Open the throttle gradually and also open the topspeed needle untill the wheels just
keep turning slowly. Let the engine run continuously for a full
liter of fuel.(watch the refueling) According to the driver the
lifetime of the engine is expanded.
This break-inn procedure will not work on
Italian based engine as was already tried also. It is worth
a try for OS enthusiastic.
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OS MAX RG 21 Sports engine Watch the minimum 18% oil percentage in your fuel when using this engine. |
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OS MAX RZ 21 A good running race engine with a good powerband. Watch the minimum 18% oil percentage in your fuel when using
this engine. |
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OS MAX RZ 21RZV-99B A good running race engine with a good powerband. Watch the minimum 18% oil percentage in your fuel when using
this engine. |
Comment received from ZORBOB@aol.com
on 16-09-1999
My buddies and I have owned 1 each,1RZB & 1RZV-99B, RZB lasted
5 gal.(18.9 liters),
RZV-99B lasted 2.5 gal (9.45 liters),Con-rod bushings gone and
took the main bearing with it!
Bummer we ran Blue Thunder fuel which contains
10%oil, not good!
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Comment received from wireedm
on 24-10-1999
Hi, I ran the OS MAX RZ V99 all this
summer and what a motor it is. Sit and idel and then jab the gas
and it would go. Has ran over 4 gal (15.7 liters) of fuel
and not a single rod or piston was broke.The only thing was that
the top of the piston had some pits in it and I think that was
from the pipe length not being right it would slide on the boot
and change the length. Was running the blue O.S. pipe with the
motor. At the start the piston was so tight I had to remove the
head and push the piston down with my finger and rotate flywheel
at the same time to unstick the piston. IT WAS TIGHT. The
method of break in was on the start box and just let motor run
at a some what hi idel to keep it going form the rich mix and
run for about 30 min at about or under 200° F and keep turning
car over to keep pipe clear of fuel. It was a very clean motor
most motors leak out oil around the front bearring but this one
was dry even after 4+gal (+15.7 liters) of fuel. Not sure
if it was luck or just a good motor. Ran Byron 20%, Blue thunder
20 %, O'donnell 20% and Trinity Monster 20% and not to sure what fuel to stick with but to
break in I would stick with Byron 20% and they all had good and
bad points. It would just come down to what track I was at for
the fuel pick beacuse the motor needed only very little adjustment
to keep around 300° F.
Comment received from Spiros
on 14-07-2000
Well for starters this is an amazing powerplant.
As perfomance goes its powerband is quite smooth and it is a little
bit "wilder" when passing from low to middle range.
Of course this is a result of a very good bottom torque. High
revs are ok. Tuning is very easy . This engine is built with hardcore
racing in mind! As an overall this is a very competitive engine
and i would reccomend it to everyone. Weak spots is the conrod
and piston. Every six hours of racing (about 6 liters) you need
to dissasemble it and check for play. Better replace a
conrod or a piston than a crankshaft! So maintenance is maybe
a little bit shorter than other engines but it is relatively cheap.
Don't forget O.S. engines are very reliable and never have flows
! (well almost)
Quality is just about perfect except the carburator which is metal
and it can be affected by high enviromental temperatures (I'm
in Greece , I know!)
Remember that O.S. engines NEED 18% at least oil because the have
high heat characteristics
With a 18% oil this engine will last very long until you have
to replace something major.
Lastly Picco and O.S. are my favorite engines due to power (Picco)
and reliability(O.S).
I'm just a little bit on the O.S. side (even though Picco have
a little bit more power) because parts availability has been never
an issue and O.S. doesn't have unexpected surprizes for you! You
can easily win having both
 |
During the Worlds 2000 OS-MAX representitive Yoshihiro
Yukami told us that some drivers like Miguel Matias were using
the new 2000 spec engine. So what is new about this engine? 1. The air inlet venturi of the carburator is now conical to get better airflow in to the cranckshaft. 2.The sleeve has an extra groove at each side of the inlet ports. When this engine with new specs is available and the name could even Kazushige Yoshida OS research & development department manager and driver not give us! |
Do we have more important news? YES.
As I was talking with Mr. Yukami during the Worlds 2000 I asked
him about that 18% oil percentage. This is the answer I got!
The manual states that you need to use at least 18% oil (he first
was thinking what the heck is he talking about). This is for the
manufacturer a safety rule he said. Novice drivers not using their
engine for racing are better of with some more oil contents he
said to get longer engine life. In the case of an engine used
for racing the oil percentage may vary between 10 to 13 %.
Sofar his answer. More will come! Why? I have Mr. Yoshida's business card with fax number so he can expect a fax in the near future
with more questions if you have them :-)
I was trying to decide between the V01b and the Picco G1 Pro
but ended up with the V01b because I heard countless tales on OS's ease of
tuning which
was a key decision factor to me as I'm not too keen on spending too much
time tuning engines!
I was comparing the G1 pro side by side with the V01b. Both were impressive and
beautiful engines, but the OS's overall finishing was much better,
especially the carb. the G1 Pro has a new composite carb, but to me, it
looked really "anonymous". there's no way you can tell that it was a
Picco
carb just by looking at it. even my earlier aluminum carb for my on-road
Picco KSR was more beautifully finished. A bit of background: This V01b is my
first OS .21 engine. My only experience with OS was the 12CV on my touring
car. Also, I had run in .21 size Picco and NovaRossi engines before but not OS.
I followed OS's run-in tips combined with Ron Paris's run-in procedure. I
sprayed some after-run oil just to flush out any debris or iron filing (there
was none) also to lubricate the engine. The OS was unbelievably tight. It
drained my 12V 7Ah at the first try. it was also chewing up my startbox's
rubber doughnut! Having said that, I should have charged the 12V first
before attempting to run in the engine. When I finally got the engine to
fire up, it was able to idle steadily but would sputter and die when I blip the throttle
slightly. Leaning out the low-end (originally set flushed) helped a lot.
after heat-cycling through 5-6 tanks, I brought it to the track to lean it
out further. (FYI, I am using Gammalube 25% fuel) I've gone through probably 3 liters
of fuel now. once I got the low-end settled, I only had to concentrate on
leaning out the top end further at the track. Even then, I didn't have to run
the engine lean or fast because our local track does not have a long
straight.
In any case, the engine has been a dream to use. The whole of yesterday, I only
had to put my MP7.5 on the starter box to restart the engine less than 3X
throughout the whole 3+ hrs of practice. It would just run and run and
run. I don't have a temp gun but used the spit test - instead of trying and
failing to aim my spit at the specific area, I use an eye drop bottle to
drop one or 2 drips of water on the engine - area around the glow plug -
the water would bubble but never sizzle so that was a good sign). I was quite
surprised with the run-time. i am using the V01B with Kyosho BSW48 pipe on a
MP7.5 and it runs up to 9 mins. Excellent!
Apart from the tight piston/sleeve at the onset of the engine break-in, I have
been very impressed with this engine. the next test will be wear &
tear over the next few months:) Oh, yeah .. I epoxy the boost chamber to the
engine because I have heard cases of the chamber coming loose because it is
merely press-fitted to the
engine. Ever since I wrote the above, I've gone through 2 gallons of fuel in the
V01b and the compression is still excellent. In the many trips to the track, I
have not had the need to tinker with the tuning. It leaves me with what I like
to do best - just run my buggy worry-free.
Thanks! Wang Yung Lik
