Originally Posted by
VS_Rody
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.