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-   -   OS R2106 (https://www.rctech.net/forum/onroad-nitro-engine-zone/1125699-os-r2106.html)

VS_Rody 05-06-2025 09:17 AM


Originally Posted by Roelof (Post 16184960)
Now some time ahead of the introduction I wonder if people have seen issues with damaged pistons with this model. It is a bit quiet so probably it is solved?

I have been reported with one incident until now, a very light seisure due to cold weather circumstances and maybe engine being a little too cool.

Roelof 05-06-2025 10:34 AM


Originally Posted by VS_Rody (Post 16184982)
I have been reported with one incident until now, a very light seisure due to cold weather circumstances and maybe engine being a little too cool.

That sounds promising

Slo-MTX4 10-05-2025 07:51 PM


Originally Posted by VS_Rody (Post 16116427)
Not Completely the same engine:)

New Piston/Liner
New Conrod
New Carburetor slide
New Idle needle

do you know if the crankcases are the same r2105 & r2106?

VS_Rody 10-05-2025 11:59 PM


Originally Posted by Slo-MTX4 (Post 16218595)
do you know if the crankcases are the same r2105 & r2106?

R2105 and R2106 same crankcase.

Slo-MTX4 10-06-2025 03:28 AM

Thank you

Roelof 10-06-2025 05:12 AM

Having some budget soon maybe do some shopping again.....
From all combo deals I see no 2165 and I was just loving this pipe and had great results!

VS_Rody 10-06-2025 07:07 AM


Originally Posted by Roelof (Post 16218649)
Having some budget soon maybe do some shopping again.....
From all combo deals I see no 2165 and I was just loving this pipe and had great results!

Made it for you : https://www.worldchampionproducts.co...r21062165.html

Roelof 10-06-2025 07:22 AM


Originally Posted by VS_Rody (Post 16218672)

Thanks, I saw it in Facebook..... but 1st I have to get some tax money back.

Roelof 11-29-2025 04:38 AM

I have received an 2106, thanks Rody for the fast service!
Timing wise it must be a faster engine than all previous models, the crank has 5 degrees more opening and the transfer ports are 1 degree higher compared with the 2105. Also on the side where the opening was extended I predict the engine should give a faster response on the throttle

Funny thing is that the exact same crank timing is used with the 5 port "sports" R21-v2 I also got. The v1 version has 10 degree less opening..... It will be THE choice for the ENS stock class.

VS_Rody 11-29-2025 06:43 AM

Hi Roelof,

Thanks for the feedback.
Basically the R2106 and the R21-V2 are the same engines, except for that there is a difference in qty of inlet ports, no DLC on the crankshaft and black anodised crankcase and a less lighter coolinghead.
For me the R21-V2 is a very good engine to start with.

Roelof 11-29-2025 07:51 AM


Originally Posted by VS_Rody (Post 16229740)
Hi Roelof,

Thanks for the feedback.
Basically the R2106 and the R21-V2 are the same engines, except for that there is a difference in qty of inlet ports, no DLC on the crankshaft and black anodised crankcase and a less lighter coolinghead.
For me the R21-V2 is a very good engine to start with.

I know plenty of people did put a crankshaft of an old R210x in the R21-v1 and the engine comes pretty good alive so now with the 2106 crankshaft it must be even more. Yes, I also believe the v2 will run a lot better as a budget engine and I think on the ENS a huge difference between v1 an v2 should be noticeable.
It is not only the amount of ports but more the transfer port timing. Both the R21 models have about the same port timings that is much lower than the 210x models, a simple sleeve shim can improve that.

Nice that you mentioned the cooling heads. I had some in reach and a new small weight scale so I could weight some:
- R21-v1: 64gr
- R21-v2 60gr
- R2106 51.4gr
- R2105 50gr
- Hasi upwards fin 49gr
- My head 63gr

And while I was busy, a standard OS P/S set weights 26gr and an Hasi AAC p/s set 11.5gr.
If the EFRA will lower the minimum weight to 2250gr or a middle way with 2300gr I foresee more weight loss on the engines like Ielasi already does with removing the upper fin and DB does mill away a lot from the crankcase.

bertrandsv87 11-29-2025 01:28 PM

Yep, the top two fins seem unnecessary anyway...That's 15grams or more: cut it out...lol...

Roelof 11-29-2025 03:06 PM


Originally Posted by bertrandsv87 (Post 16229787)
Yep, the top two fins seem unnecessary anyway...That's 15grams or more: cut it out...lol...

Well..... it is a known thing that the top fins are taking a small part of the cooling but with the high position of the body there is hardly a fin sticking out with a cut off head and then I think a full size head sticking out more above the body will provide a better cooling. But hey, Ielasi does now sell a thick plate of aluminium with which you can raise the head.

SEF450 11-30-2025 04:59 AM


Originally Posted by Roelof (Post 16229720)
IIt will be THE choice for the ENS stock class.

Plan to run the ENS next season? (considering seriously...) Finished break-in the R21-V2 and taking my time on the Euro Spec II (liking a lot of it with the 2115 pipe).

Thursday surrendered and got into (additional) problems ordering a 2106 with other bits from Chez Rody (ETA: Wed). Thinking seriously to look for an oil break-in for it (forgot to add the EBIS option while I was ordering... :cry:).

P.S: Still not sure if the 1F400 model (Ver 2) will be accepted on the ENS next year. But gambled about it just in the case... :D If not. Is a nice practice one for winter time with low low traction on my track.

bertrandsv87 11-30-2025 01:57 PM

I would prefer to either drop the body a bit or drop the air channel part of the body that cools the motor...


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