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So I folded and bought the new yz-834b re re and I've started looking around it and comparing it to my original.
As has been mentioned elsewhere nearly every part is to some extent different to the original, there are the more radical changes like the gearbox using 32dp gears over the original 0.8mod , this makes the whole gearbox different , further the chain pitch is a different pitch , same as a lot of Kyosho chains and larger than the original, so sadly no new gears , chains or sprockets to refresh your old dog .
The wheels are very similar but now have tyre retaining ribs and a breather hole that was not there before . The rear trailing arms are an odity , they seem to have used the very early design with less reinforcement ribs compared to the much more common later design On the bright side the entire trans would drop into an original chassis and it looks like you could transplant the front spool as they are , well to say rare is an understatement
The top deck/chain guide needs trimming at the rear as it fouls the chain cover on the side of the gearbox but worse up front the bracket that stabilises the servo saver is too deep and pushes the front up 3mm above the front bulkhead, you can space it up with washers but first you need to drill the hole from 3mm to 4mm and countersink it as they are now secured by an M3 countersunk screw instead of M4 . All this has been done to raise the top deck so a lipo shorty pack will fit under it , a good reason but it's a pain if you like me were hoping this would be a drop in fit .

To be fair modern polymers are way better than they were in the 80s so the ribs may not be needed.

I actually put off getting one of these in favor of an optima mainly because I want to build something and the 834b is mostly assembled.

May get one later on but not now.

RogueIV wrote: ↑Wed Oct 02, 2024 3:44 pm To be fair modern polymers are way better than they were in the 80s so the ribs may not be needed.

I actually put off getting one of these in favor of an optima mainly because I want to build something and the 834b is mostly assembled.

May get one later on but not now.

I agree totally , the modern rear arms are stiffer than the old reinforced ones .
I know what you mean it's not a kit but then they never were so ..... Still you do have to pull it apart a bit to fit the motor and fill the shocks .

Mine is good to go, went with a cheap shorty lipo as the stick liop I was planning on using did quite fit with the body on. The stock Yokomo Motor seems to have a bit of punch for a 27T but I've only run it around the living room (hence the dog hair). One problem I had though was the rear two screws on the top deck stripped out immediately so I had to take the gearbox apart and fix them using some super glue and this Q-Bond powder I have, I then drilled and tapped them so they are much stronger now. The plastic on the gearbox and other parts feels a little flimsy but the gears and diff seem okay - not sure if putting a brushless motor in would be a good idea tho.

I also put some original 870c rims I had lying around on with some mini pins - the slightly different offset on the wheels meant that the inner was a bit too close for my liking to the trailing arm so I used an o-ring on the hub to space it out a tad. Also the centre hole diameter is larger on the later wheels but the hub is the same size so they do fit just not perfectly.

With the car fully equipped the rear seems to be a bit on the low side and I can't seem to add enough preload on the kit spring to raise the height enough - I might put a stiffer spring on before I run it proper, or have a play with the turnbuckle lengths to see if that makes a difference.

I can't really compare it to an original as this is the first one I've had but overall it is a cool buggy and very different to the later 870'c and works cars.

RogueIV wrote: ↑Wed Oct 02, 2024 3:44 pm To be fair modern polymers are way better than they were in the 80s so the ribs may not be needed.

I actually put off getting one of these in favor of an optima mainly because I want to build something and the 834b is mostly assembled.

May get one later on but not now.

I'm going to revisit this as I've noticed the rear trailing arms do twist more than the later version originals ,seriously thinking of getting some stiffeners from Factory works .

Tbh I have never done a side by side comparison with and without the stiffeners, but they are made from .030 thick (~0.75mm) g10 (which is what Hot Trick used, and limited by the arm mounts) and I just don't know they they do a whole lot other than add the classic appearance.

GoMachV wrote: ↑Fri Oct 04, 2024 5:49 pm Tbh I have never done a side by side comparison with and without the stiffeners, but they are made from .030 thick (~0.75mm) g10 (which is what Hot Trick used, and limited by the arm mounts) and I just don't know they they do a whole lot other than add the classic appearance.

Jeff, Jeff, Jeff, we all know that classic appearance itself does a whole lot.