RB5 Hopup

[caneye]

new kyosho upgrade for the rear-end.
timely upgrade...

Part #.UMW510
http://www.kyosho.com/eng/products/rc/newparts.html

seems to include
- shock towers
- rear mid-conversion arms
- shock bodies (shorter? velvet coat?)
- springs
- rear bones

[dgrobe2112]

wonder what all is included.. why would they just offer the rear end upgrade.. and not the front shocks too..

[RogerM]

This conversion covers two up-grades

Wide rear track conversion (often called the rear-mid)

This uses the rear arms (LAW243 .... explains why there are original ZX5 front arms in teh RB5 upgrade pack as they are on the same sprue) from the ZX5 LAW34 upgrade which narrowed the track width of the rear of a ZX5 and drive shafts to suit.

This conversion is popular on the US tracks as it actually makes the car a little more stable on smooth surfaces and the resultant geometry actually makes the car pivot more too. It is normally used in conjunction with the original ZX5 rear shock shafts (54mm) to allow the new outer hole to be used on the wishbone .

I have tried this conversion and it is spectacular on indoor tracks or where most corners are just the end-of-a-pipe style hair pins ..... the pivot effect is huge compared to the stock rear end.

I feel that it isn't as good on normal track layouts and is no where near as good over the bumps as the stock rear end .... all my parts are in the box, probalby never to come out. That said I know there are people out there that love it, all about how you drive.

Shorter rear shock conversion

Again this has been used by some of the US / Japanese drivers and was seen at the last worlds.

With the standard rear shocks you have a load of unused potential travel in the shock bodies, this conversion removes that and takes the pistons to very near where the top of the oil would be on an extended shock! The shock bodies included are the latest "velvet coated" units ... if you want matching ones for the front you'll have to buy those separately.

Opinion is devided on the benefits of this, even if there are any at all.

The most obvious is a slight lowering of the tower, which brings down the C of G a fraction.
I am not sure if the new tower will have the same resultant shock angles as the current tower or if it will be stood up a little more like the B4 is .... I personally hope it remains as it is at present.

The only other things in the conversion are the new hubs which are just a single hinge pin hole version of the current hub (part number UM519 I think) which is stronger .. ok near bomb proof and a set of blue springs (think they are the #68 springs) to suit the common set-ups used with this conversion.

I hope that this clears things up a little.

[caneye]

wow .. thanks for that info

[SimonW]

I'm not 100% on this but i think the new blue springs are 72# rated

[wouter.z]

Originally Posted by SimonW

I'm not 100% on this but i think the new blue springs are 72# rated

your right they are 72#, i just got them from speedtechrc.

[RogerM]

Kyosho's latest blue spring is indeed #72 rate (i.e. between silver and light green) but I believe, although not 100% sure, that the springs coming in the RB5 upgrade are the #68 (i.e. between yellow and silver) springs.

I can not get a 100% answer to this at the moment and when I do I'll let you all know!