HG-P407 "Bruiser Clone" Arrived Today!

[Coelacanth]

What is the total expanded length of the shocks, from the center of each eyelet to the opposite?

[Basher67]

It's 85mm from the center of the bottom eye to the end of the top shaft.

[Coelacanth]

Hmm, that's pretty close to Kyosho Gold long shock length...those are about 90 mm, if I recall correctly.

[Dadio]

Why did they decide to fit the little spring over the shaft ? , I'd be interested to see if they are smoother without the spring ?
Mine should arrive in the next 10 days but possibly less , the tracking shows its been flying from China to England for 48 hours .

[Basher67]

IMO the spring over the shaft is useless. The rest of the suspension is so stiff, it doesn't notice if its there or not. I diassembled this shock while I had it off the truck. I tried some different weight fluids. The first thing to address, I think, will be to enlarge the piston holes. Even with 20wt oil, the shocks would rather leak out the end than cycle. The floating brass piston and shock stop spring are also a joke. Something that is cool in concept, but is not even close to working properly. I'm thinking when I get a few minutes to play with it, I'm going to eliminate all that useless stuff and rebuild the shocks properly and enlarge the piston holes.

[XLR8]

[Dadio]

I'm assuming the floating brass piston has an O ring and bleed screw ? , is the O ring over tight causing the floating piston to be too tight ? I've had some success with resizing the O rings in other applications , if it has the bleed screw then replace it with a long screw and use the extra thread to fit into a drill chuck , spin it up in a drill and use very fine wet n dry 600+ grades to take a little off the O ring until you get a better fit . I'll try it on mine when it arrives as well as removing that spring .

[Dadio]

Mines in the country , I'm just waiting on a red postcard from the post office telling me I have customs charges to pay .

[Dadio]

Yay my P407 arrived , what's more I dodged the customs charge as well so I'm pretty chuffed at that as well ! .
Where to begin , I guess the good stuff first .
Good
You get a lot for your money , mine came in pristine condition with no packaging damage or loose bits floating about at the bottom of the box , I've found no missing or loose screws anywhere , everything works as it should right out of the box , gears shift fine and there were no nasty noises , in fact it sounds really smooth ! The tyres are not as soft as I'd like but not as hard as I was given to expect , I've got a RE RE Scorpion and the front tyres on that were like ice hockey pucks ! All the cast parts look superb and in fact it all looks very well made indeed . The axles both have nice red grease in them and the diff's feel very nice . The body is detailed and well made and fits together well .

Bad
Two of the three screws holding the right front wheel on had the hex stripped out and could not be removed with a hex key , I had to grind through them with a dremmel bit , very nervous work as I had to keep stopping to let it cool so it didn't melt the wheel but I got them out eventually . I'd planned to remove a spring leaf off each spring and try to sort the shocks a bit as well as locking the diff's so I got quite stuck in , the springs were easy to do , the shocks went well on three of them but not the fourth , as has been mentioned these shocks are scratchy and the piston is too close a fit making them leak , firstly the scratchynes is caused mostly by the circlips above and below the piston not being seated properly and touching the inner cylinder of the shock ! These circlips are dreadful I had to replace a few of them but once seated the shocks are much smoother , I also filed two flats on the sides of the pistons to let the oil pass easier , this worked well and felt good with 10wt oil , the shocks other fault is the floating piston at the top , three of them worked well but the fourth had too deep a groove for the O ring and made no seal at all , for now its wrapped in plumbers tape to seal it but I'll make another one on the lath at a later date .
The last bit of bad is the diff locking pins not aligning with the holes in the axles , you should be able to remove a grub screw from the top of the diff , align the diff casing and one half shaft and drop in and screw up the locking pin but both axles proved to have alignment issues , I removed the rear axle an stripped it down to find the problem , what I found was the hole in the half shaft was .5mm out of alignment so I could get the pin into the axle casing and into the diff casing but not into the axle , five minutes dremmeling and all is good , I've not had time to strip the front axle yet but I assume it will be the same .

Overall
If you don't intend fixing the shocks or locking the diff's or to do any climbing with it then its all ready to go out of the box , so much of it is superb quality and for so little money its very hard to complain but it is not Tamiya quality and you can't expect it to be . With the suspension I found the sweet spot is to remove a leaf all round and remove the rear coil springs from the shock shafts but leave the front ones in place . The tyres are OK ish but I'll swap them for a softer climbing tyre in the not too distant future .

Probably more tomorrow after looking at the front diff , I'm not sure weather to lock it or fill it with 500,000 diff syrup , I'm leaning toward the syrup .

[Dadio]

Well I've finished a fairly comprehensive teardown , final tally of five screws needed attention to remove them and then be replaced , the gearbox was dry as a bone , no lube at all so that got a partial strip and full lube , the front diff locker needed the same work done for the locking pin to fit and I can also report that the diff was well greased with the red waterproof grease that the rest of the axles got, I cleaned out the front diff and refilled with 500,000wt diff syrup , I can still lock it later if I want to but the syrup gives a good compromise . All in all the only parts I've not stripped are the chassis rails and the spring hangers so I've been quite thorough so to sum up for tonight
1 the screws are made of cheese and I'd recommend replacing them
2 both my diff lockers needed to be stripped and some dremmel work done in order to function
3 the shocks are awful , I was hopeful that I could rework them but now I think they have to go
4 the tyres are not as bad as I feared but still need to be replaced for better crawler tyres
Its taken me a day to tackle the mechanical issues with the stock RTR and for some it might have been a daunting task however if you have the skills then you end up with a very cheap Bruiser clone of a high standard and none of the problems are going to return they are just build and manufacturing tolerance issue's , mostly just cheap screws being used but they had to use cut price parts to keep the cost down ... I'm happy so far and I'll see how happy I am in a months time.

[Basher67]

Great write-up of your experience with the rtr. I'm glad you decided to add it to this thread. It sounds like you confirmed my issues with the shocks. I haven't totally given up on them yet, but I don't have high hopes. I haven't looked around much at options for replacement. I was surprised to hear about the gearbox being dry. I need to inspect mine to see if it is the same. It operated so smoothly and quietly that I never checked it out. I didn't notice if you said you got the black or the white one. You should add a pic of it, especially if it's a black one.

[Dadio]

Its a white one ,I'll be painting it and I thought white is a better base colour , I'm not sure what colour's to go for yet. I've got some tires and a lighting kit coming as well , I had money set aside for the import tax that was likely to be £40 ish after the PO add their handling charge ! So it was a nice bonus that it slipped past untaxed .

[Dadio]

From what I read on other forums none of the gearboxes have any lube at all so I'd have a look if I were you . Another thing I've seen two other people mention is teeth being stripped from gears in the gearbox , metal gears as well but all the parts are on banggood so all is not lost.

[Dadio]

Today's planned tasks were to replace the servo and remove the servo saver , I had a slow high torque metal gear servo that I ordered ages ago by mistake so that went in with a regular servo horn , all went smoothly and really transformed the steering .
Outside in the road during testing I had a Scooby Doo moment as the left front wheel fell off and rolled away at first I thought the three screws had fallen out but it was the nylock drive flange nut that had come off , after a ten minute hunt for the big roller skate bearing I though I could just put it back together with a little locktight and all would be well .......NOPE ! When I tightened up the nylock nut up it locked the bearings in the knuckle ! The bearings only turn if the nut is left slightly loose ! I stripped the other side and found it was the same , I was hoping to find a sleeve was missing but no such luck . Fortunately for me I own a metal working mill and have a 10mm end mill that I could use by hand to deepen the inner bearing hole in the knuckle slightly until I could tighten the nut without it locking the bearings .
There's been a lot of speculation that the casting moulds were the same as the ones used by Tamiya but I just don't believe Tamiya would would have fit issues like this .
I'd be interested if other people have this problem as well .

[Dadio]

Lots of trial and error but I got the shocks working and the oil to stay in !
As I mentioned earlier the pistons have to have two flats sanded onto the edge to allow more oil past them , the bottom seal for the shaft I added a small 2.5mm inside diameter O ring and removed the metal washer , the cap take's a bit more force to screw up but the additional O ring makes a good seal , finally the floating cap , this is the tricky bit , you have to pry out the O ring and that's easier said than done believe me ! then use some PTFE plumbers tape to wrap around inside the groove the O ring sits in ,I found two times round was the charm , then re fit the O ring , the cap should now have a good tight seal but still move up and down with the volume change .