Been looking at the site my views:
Website looks clean and tidy.
I like the fact you've added a good description for items
You seem to stocking the full range or parts from shs not just a few select item. (I think these http://www.majorairsoft.co.uk/shs-fibre-reinforced-lightweight-piston-with-15-metal-teeth/ are the best pistons on the market and you guys seem to be the only people in the UK stocking them)
It would be nice to seem some more unique/rare/hard to find items. This would help separate you from other retailers giving you a USP.
I would also pretty much agree with what Hef has said.
I'm another one that wants a G3, got a friend that has a TM G3 with a metal body kit, looks awesome and doesn't creak!!
Also does anybody know whats happening with TM HK45? I want one but they are all out of stock everywhere, last I heard they are having issues with the trades.
Here's my heavily modified TM MP5K
I get my 0.2g in bulk from http://www.patrolbase.co.uk/airsoft-bbs/0-20g-blaster-6mm-bb-bundle-12-x-3000.htm#.VfA48xG6dpg £59.92 for 36,000 ASG 0.20g Blasters
Either blown fuse, assuming it has one or as Monty states, you've been sold a faulty gun. You could "short" an airsoft motor 9.6v battery even if the battery was the size of a house.
Yeah it's a core, got a few of them ages ago from AK2M4 to rewind. Yeah the polarity was wrong, swapped the pinions for SHS ones, as you said the stock pinion could be better, But for a cheap neo motor for working they are pretty good.
True, he doesn't say anything about testing velocity change vs distance but the theory is sound, considering it's nearly 10 years old and there has not been any real major challenges of it's accuracy it's not bad.
There is this one http://www.arniesairsoft.co.uk/articles/fps_dist_time/fps_dist_time.htm which does have higher values for the results.
Both of these are in the US but ship to UK.
http://www.clandestineairsoft.com/scatterplot-laser-cut-sorbo-pads-c-1_6_18/
http://www.brillarmory.com/index.php?main_page=index&cPath=49&zenid=nhrhmlmgidnkuvpcg21mbnnfq7
https://www.youtube.com/watch?v=FlV5peGEnag This is how you test how good the compression is. i
If the compression is fine try this method https://www.youtube.com/watch?v=MFnUjxdiXuU.
if that seems ok, watch this https://www.youtube.com/watch?v=jj0mM8A2C3A# to find out if the nozzleand tappet is ok. The video also shows how to change the motor height.
If the nozzle is fine then it is probably the spring that needs changing.
I would recommend having a go at fixing it, it will be a good learning experience
The FPS loss is going to be either a compression issue or the nozzle is not engaging properly.
If the handle is getting hot it probably means the motor height needs adjusting or/and it could need re-shimming.
Has the previous owner been taking the gun apart?
Best to keep the High speed motor assuming it's got neodymium magnets and use a 7.4v LiPo. If you use the stock motor and an 11.1v LiPo you will most likely suffer from overspin as most stock motors use ferro magnets, motors with neodymium magnets stop a lot quicker thus less overspin. #
You need to determine what you want from the gun e.g. high rate of fire, quick trigger response, etc.
If you want great trigger response but not high rate of fire you I would recommend a ZCI High torque motor and a SHS 12:1 gear set. The ZCI is slow but has huge amounts of torque (it will happily pull an M170 spring on a 10:1 gear set)