Yes 185g is pretty average. I've had a 280g syrian! And a couple of 220g syrians. They weren't overweight though, they were just large syrians. Average is probably between 150 and 200g. And hamsters tend not to get overweight anyway. As you say Stanza, they only eat what they need. Also it's almost better to have a bit more in case they ever lose weight due to teeth problems or other illnesses - when they can lose a lot of weight quite quickly - so keeping a healthy weight is good.
That is a really good idea also to use a litter tray. One thing that can happen after a full cage clean is, if all their scent is removed, they go round peeing on everything to scent mark it and claim it! Normal scent marking is from their scent glands, but if they feel they need to reclaim their territory or deter invaders, they can pee on things so scent mark them. Then it becomes a bit of a vicious circle! They pee on more, so you need to clean more and so on. But you can just spot clean and wipe the odd thing occasionally.
This is a particular thing with hoards. If all the hoard is removed they tend to then pee on the next hoard - to try and deter thieves possibly! And mark it as theirs. Which is strange as then it's virtually inedible! Sometimes you do have to remove the entire hoard, if it's going mouldy or pee'd on - so the trick there is to replace it with new food - in the same place. A good handful of new food. They seem to accept that. It helps if you can save a tiny bit of the old hoard and put that on top - so it still has their scent.
They will usually use a litter tray if you put one out - they will almost always use one - then life becomes a lot easier - as you only have to empty the litter tray! But - they will only use it if you put it in the right place! They usually choose a corner of the cage as a toilet area (or a corner of a large house). If you put it in a different corner they will ignore it. If you put it in their chosen corner they will use it as a toilet.
If a hamster pees in their house then adding a litter tray in the house can stop that. I've found that with large houses/nesting boxes, they almost always move their pee corner inside the house - they seem to like an ensuite bathroom, in private, if there's enough space! Multi chamber houses and large houses allow for this.
I get these corner litter trays - they fit well inside a house and are a good size for a hamster - and just put chinchilla sand in it. The first time it's a good idea to put a tiny bit of pee'd on substrate on top of the sand so they realise it's for peeing in. They usually pee away from the nest so that's a good place to put a litter tray. Sometimes they only pee in the nest out of laziness! But it there's a litter tray nearby they will use it.
I've only had one hamster who took a long time to get toilet trained. All the others used the litter tray. That one would use the litter tray - but would still pee in his nest as well. He got there eventually but it took longer!
They like to hoard and pee somewhere private and enclosed. So if there isn't a litter tray he could well choose to pee in the tubes.
This one is a good size for syrians - not too big, not too small. Our first hamster was very neat with his. He would pee in the very back corner (it's raised at the back so prevents splashes) and then sit in the front part for a wash!
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