Almost all of it has come from automatic payouts from this pool -
http://bcn.extremepool.org/#, mining using one 270 and CPU - payments range from 60 to 100 or several hundreds of BCN. Previously I had 5k BCN which were withdrawn from minergate and 2 hours ago I cleared some 62 BCN from there, to level my balances there - not sure did they arive since it's a small amount.
So that is the reason. You have a lot of small inputs that is why your transactions sizes are out of limits.
I guess you can transfer your coins to another wallet (in order to generate bigger inputs) and use it instead.
A lot of users suffer from this problem caused by weird pool's payments
Thank you for your answers, but...
Regarding this problem from a few days ago, it just got more worse and I really dunno is it big or not. You be the judge of it...
Since I couldn't deposit to poloniex 100/50/40K BCN I sent a few smaller amounts.
-The first chunk was 10K BCN with transaction id: 234ffcab1db2a972d6f6c6a9a2d18f5d989fb5cc065a0c8ee71958e0cb88656c - all went well, deposit arrived, transaction is in the blockchain.
-The second was 15K BCN and also wallet said it was successfully sent, transaction id: 8c1113eeeb7462e4f01f2f927ba07b23c59c1f9976e393a3edf3dbfdd087d1a2 - 3 days later didn't show up as deposit, polo rep said he can't find it on their end and it is not in the blockchain.
-The third chunk 15K too, sent with id: db06a0075e57a48d730f542ef8cd8f37460d9a448cc2149da7adf0ee91219917 - deposited, in blockchain.
-The fourth, fifth chunk and sixth chunk all with 15K BCN, were sent with following ids: f6b6b1ec2a5f0c2093eff923160187876f03271074234c03c38365d8e7fe7f10 , 6fed382f25dadb8d7ce7a1eea0d758b570c5b0ddb012ff308651f2b99b5791eb , 180e159140e4df3e7ff5094163d34d5fb58b1afc6368812960e8f016bbb9fce2 - missing, not in blockchain.
-The seventh chunk of 15K, sent with: cb12f673f0776ec60d9a913b44cdc708f3cd35a707089b2db458521d95fe8cca - deposited, in blockchain.
All were sent between 13.00 and 16.00 on 3rd of July... In the process I sent 10K first, then after a few minutes 15K, then one more of 15K and then if I recall well I exited the wallet and the daemon to restart them and sent the other 4 chunks of 15K BCN. As you can see there's no specific order which of those passed through the network.
So, where are the coins? Please understand me, the amount of lost coins is not a problem, but if this is a bug you would have to agree that it is a serious one if they don't show up on either end - back in the wallet or at poloniex deposit address.
BTW, transaction ids were dug from the simplewallet's log OFC. After sending 100k in total my balance was down form 310K BCN to 210K BCN, in the last 3 days I dug more so I'm sitting at 325K - want to point out, since I'm mining with 1 270 card it is correct amount payed out from a pool and that coins left the wallet.
And finally I just conducted a test, sent 25K to poloniex, transaction id is ee80d6b229bfacba7ca8f49d1bd1864f8ee8b669a5d351bc5df2be2445fd0da1 it's not there yet, I hope it will pass through the network or I can say that I'm stuck with wallet address and no way to transfer them to other wallet. Since I intend to do that, open a new wallet and transfer coins there to avoid transaction size limit.