OS speed R2101
 

Hi guys,
I have a question regarding the above mentioned engine.
I got this engine from a friend of mine. He bought it last year in Japan during the World's.
It should be an engine which was made for the japanese teamdrivers.
See also art. picture...
Can someone tel me if it is a special modified or same then the standard one?

The OS 2101 was quite readily available during the Worlds in Japan last year.
Unless your friend got it from the team driver, maybe it is special. :)

No he got it from a Futaba shop. But they told him it was the pre engine for the teamdrivers.
I know that for example Novarossi mark them with a red dot on the rear side screw.
Can't see anything on my engine.
I am just asking because I am interested.
I will see after breaking in :-)

It's a standard.. :)

I don't know if the team drivers like Hara and Shimo are running 'team' R2101s but the only special OS R2101 I saw was the Maxima R2101 on Gilles' and maybe a few more other drivers.

Isn't it just a replica?

Mostly manufacturers do produce a WC replica engine because people ask for it.

The Maxima version? A fair bit of work was put into it from what I saw

Hi ,

On the engine if you see letters WC2013 and the number for the engine then it was for team driver .

Regards

Ok. It is a normal engine then.
There is no number on the crankcase, only the letters RH on the mounting flange.

How is your experience between the OS and the Novarossi 35 plus QC?
Which one is for technical narrow tracks better?

OS provide better torque than 35 plus

Those who have tried them here in the UK have said they have a lot of torque and need gearing higher than other motors, the fact it produces it's peak power 8000rpm lower than a Novarossi probably has something to do with this.

We have a few drivers in the UK running them, be interesting to see how they go!

In Japan, it has a limited edition of 200 sets. With matched piston set,....with pipe.

main bearing failure
 

Hi guys,
Here a quick feedback and hopefully replys on how to do now...

After breaking in the engine with the heatcycle method (about three liter) I joined this weekend our club race.
After finetuning the engine went really well, couldn't even use the power on many parts of the track..
Highest measured temp was 116℃. Adjusted to 100 to 105℃ afterwards.
Ambient temperature was 27℃.

After the first main the engine lost dramatically on power and died several times...
Tod I disassembled everything and found this:
Piston/sleeve have several fine scratches (mainly on the intake side)
Main bearing has about 0.1 to 0.2mm radial gap and about 0.1 mm axial gap - it sounds now like a music instrument
Conrod has on the rearside also scratches
The crankcase has deeper scratches on the bottom side - comes from the crankshaft


I guess it is a bearing failure. The crankshaft created metal shavings from the crankcase and they came to the piston/sleeve.
Do you guys think it is useful to contact OS for this?
PS: airfilter was brand new and temperature gun was an exergen...

Picture
 

here is a picture of the crankcase.

You can see the touching area which comes from the crankshaft on the bottom right next to the groove for the conrod.

I can press the crankshaft easily by hand against the crankcase - with mounted bearings....

picture

It wouldn't hurt to send the report into OS and see what they say. What fuel were you running as it look like there is some corrosion on the bearing outer race??

Sounds like the rear bearing failed maybe?, could be due to lack of lubrication/engine being too lean?

It's always a real heart ache blowing up a .21 on-road engine, they aren't cheap!

Hope you get it back up and running soon!

I'm not too good with C deg, In F deg is close to 240deg, Ambient temp at 80deg. It stalled out a few times cuz its too lean. Richen your LSN a bit, get it to 220-230C be a lot better. What % of nitro you using? Crankcase really looks too dry, unless you wipe it off with a paper towel!

Hi guys,
I use Tornado 25% fuel.
What I said the highest temperature was 117 C when we readjust the engine only for one lap.We run the engine at 100 to 105 C which is 220 deg F.
I don't think the engine was to lean, had lots of blue smoke coming out and it died always in a very slow corner...
When I disassembled the engine and saw the piston/sleeve I thought damn I got dirt into the engine...
So I started cleaning the crankcase, piston, sleeve and bearings. The carburetor looks clean, had only airfilter oil on the intake. During the cleaning I found fine metal shavings and heard that the bearing has excessive play...
At that time I removed already all the lubricant.

I contacted OS - still waiting for their feedback.

Michael

Your rear bearing is corroded. That is not a manufactor defekt. It is clear in the picture of your crankcase. That will eat ceramic balls very fast.

I love mine... Its a torque monster with a ton of mid range but very little top end

It is quite normal for bearings to fail, specially the rear.

If you are looking for answers why? It can be many factors, including being too rich. get new bearings, look on youtube how to change them (you must take of carby and all components and put in the oven and readh 150c and they can fall out or a small tap.

then warm up block and put back new "cold" bearings in.

Do not attempt to run the engine as it is.

They're producing their peak power somewhere in the region of 8,000 RPM lower than a Novarossi Virtus for instance, this means you're going to have the gear the car completely different, you need to keep gearing taller until you get that top end back with the OS engine.

How's this engine?

all i can say its amaze me even i got some minor problem due to rich on my qualifing heat but in final the engine totally give amazing power and torque, the temp of my engine give suprise 80deg till finish the race,usually my zac r2101 and my nova rex peak temp 130deg - 150 deg at 36deg wheather :D

coming from NOVA 35plus21 , I also love it
finishing the break-in period and now , will definitly see what it can produce
so far , easy set-up , easy breakin , can't wait to see more
already satidfied with the power delivered

Hope you sorted the issues out with your engine. This is the single best engine I have run with no problems.

Anybody using or have tried the HIPEX 2115 pipe with this engine yet. I know Collari uses it on his modified R2101 engines. Just would like some thoughts on how it compares to the OS Speed pipe.
I will be doing some back to back comparison next weekend at our first race meet of the year.

feedback
 

How was your testing? Which pipe /header combos did you try? Results of the performance?

HIPEX PIPE results.
 

Hey there fellow OS users. One the weekend I tried the short manifold with the HIPEX pipe. Results are not totally conclusive but the first thing i did notice that the pipe did give a bit more top end or the OS OEM pipe set, run time was much the same. Power band delivery was a bit earlier with the hipex pipe.

This weekend we have another race meeting and I will try the medium manifold and report back the results. I will have better data after this weekend as I can give a comparison on all three pipe combinations.

Sorry if this is not a totally comprehensive post on the results. But so far if you are keen to try these HIPEX pipes and manifolds, I would no hesitation in suggesting anybody trying these. They are excellent value for money and are very well made.

Stay tuned for another post after this weekend.

hypex
 

HI
Collari use 2069 HYPEX with conical C-
which pipe you used exactly. explain with better details . For you the HYPEX is better 2115 is better

A couple of pipes tested but still feel the OS to give the best results
APlus pipe cheaper than OS pipe no change of performance but less decibel sound
Hipex pipe set med header felt good
Nova 2015 with OS header less runtime improved mid range

Collari I believe is running a massaged version of the R2101 - my motor.

Need help with an header for a 18tz modified engine and pipe. Also what is a good filter To run with it. Going in a natrix 748.

Really want to match that motor up with an ERCm small block pipe

Rody is working on the OS motors now too, offering up a massaged version of the R2101 with includes breaking in if you so desire.

I am not sure what ZAC project is doing with their verions of the R2101 given that they have worked over the 12XZ

APlus EFRA 2110 Tuned pipe set.

anyone know what the stock clearance is between button head and piston on the r2101

thanks

According to the "Destruction Sheet":
"The engine is installed with a 0.1mm thick and a 0.15mm thick gasket for 25% nitro fuel when it leaves the factory". :tire:

Thanks but was looking to see if anyone used solder to see the clearance inside

+1, Piqued my interest but perhaps some putty would be more pliable and cause less strain on the con rod. As they do with full size cylinder heads.