RPM narrow chassis wider arms?

[Chewbacca]

Hi all,

I know there are multiple threads about wider arms and what CVDs to use, here's me question:

I have narrow cut (rpm kit) tub with truck nose plate the long rpm arms front and back.

Combined with HPI super stars in the rear it seem a bit narrow in the rear.

Can I use the truck arm in combination with B44 / B4 CVDs?

Thanks, Tony

[yellowdatsun]

I run the truck nose plate and truck arms. Super wide, and really help with those off-camber landings. Looks normal until you set it next to another car, then you can see the width difference.

[Chewbacca]

Hi yellowdatsun,

I think you missed my intent. The front is fine with truck nose and wider rpm arms. I basically want to get to the NIX width in the rear, but with a now narrower chassis in the back.

The car has the RPM narrow frame conversion.

Thanks, Tony

[Asso_man!]

Hey there Tony, the truck arms will be way too long and won't work with B4/B44 Cvds which will be too short. The HPI wheels should work fine depending which one you use. Are they the hex type that are used with adapters or RC10 specific ones? You should use the proper larger adapter with B2 type axles. Good luck!

[Chewbacca]

they are hex type with the HPI truck wheel hex adapters (centering ring cut off).

My goal is to get to max legal width, but I now have a narrow chassis with the rpm mounts. Would B2 arms (good luck finding those) add up?

Has no one done this so far?

Thanks, Tony

[Asso_man!]

Pics would help a lot

Here is my RPM chassis with stock front axles and CVDs, front wheels are stock AE and rears are 2.0 HPI 5-spoke wheels.

[Chewbacca]

Thanx Asso-Man,

For that pic. So, I have a tub cut down to the Rpm width, with the rom mounts just like your RPM chassis.

Now, has anyone here added wider arms to reach max legal or Nix width?

Thanks, Tony

[Asso_man!]

Thanx Asso-Man,

For that pic. So, I have a tub cut down to the Rpm width, with the rom mounts just like your RPM chassis.

Now, has anyone here added wider arms to reach max legal or Nix width?

Thanks, Tony

Not sure anyone has done that before with RPM rear mounts and long arms. You could think of using 0.125 Custom Works spacers (http://www.ebay.com/itm/NEW-Custom-Works-Rear-Wheel-Spacer-125-2-7208-NIB-/390840622149?hash=item5affea9c45) to get your stock configuration a bit wider in the rear and use these on the front: http://www.ebay.com/itm/Associated-7222-Wide-Front-Axles-2-RC10GT-RC10-Worlds-/301178875470?hash=item461fa8ee4e or experiment with B4 rear hubs and B44 CVDs. You could also try using teh conversion kit AE has released with the re-re Worlds' car: http://www.ebay.com/itm/TEAM-ASSOCIATED-6002-1-10-RC10-WORLDS-CAR-REAR-HUBS-WITH-BEARINGS-/381367716537?hash=item58cb498ab9 and http://www.ebay.com/itm/NEW-TEAM-ASSOCIATED-RC10-WORLDS-EDITION-Axles-Rear-AR4-/311402734616?hash=item48810ca418
Then there is the 3D printed way: http://www.rc10talk.com/viewtopic.php?f=35&t=38327

[Phin]

What's the width of an RPM narrowed rear end compared to the rear of a B2/B3?

Could you post the center to center measurement from the hinge pins in one rear arm mount across to the other arm mount on your RPM cut RC10....and could someone with a B2/B3 please post the same measurement?

[jwscab]

no-one has really done this because the goal for many of these 'whats old is new' cars is to run b4 wheels, so the offsets and juggling were to achieve that. The rpm worlds style cars are not common so not many racing these and concerned about max roar width. the arm mounts are hard to find and are a commonly damaged part so with no supply or replacements, not many run these cars consistently.

Is the car completely assembled with universal drive shafts or dogbones?

if the car is together and the driveshafts are working properly, you have the right/correct arms hubs and axles on the car, and would use standard rc10 wheels to give you the nominal track width like the picture above.

If you are trying to achieve a wider stance(not sure how much more you need), then you need to start looking at a couple of items.

1. find out how much you need to get to the width you want. If it's not much, you can maybe juggle a wheel/spacer arrangement to get you there.

2. B2 arms are slightly longer, B3 are 1/8" longer than B2. RPM worlds used rc10 universals, which are same as b2/b3(except axle diameter), b44 rears are slightly longer, and b4 rears are longer yet. B2 used truck style hub carriers, same offset as rc10, and b3 hubs are 1/8" narrower. B4 rear hubs move wheel outward but you need to juggle dogbone length. re-re worlds uses newer axle type with b44 rear mid driveshaft, so it's a different length, but not sure if longer or shorter.

if you can find a wider arm, you may be able to use a b44 front mid driveshaft and re-re axles to get the length you need, but that is just a SWAG.

[yellowdatsun]

Yeh, I do have the truck rear arms with B4 wheels. I don't know what the Roar width is, but I'd be surprised if my car fits that. Fine by me, since I only drive it at the track for fun, and the width keeps my "incidents" to a minimum, thereby keeping the car in better shape with less damage. I can see what you're trying to do now though.

[scr8p]

I think some pics would help here.....

But, it sound to me that if you would use proper rc10 rear wheels your problem would be solved. Correct?

[Chewbacca]

Not quite. I do have proper rc10 wheels and will check. It still won't make the car any wider than RC10 standard.

[scr8p]

I was just assuming, since you were using HPI wheels with a hex, that they would be a modern 2.2 wheel which I believe has quite a negative offset.

[Chewbacca]

Thanx Asso-Man,

For that pic. So, I have a tub cut down to the Rpm width, with the rom mounts just like your RPM chassis.

Now, has anyone here added wider arms to reach max legal or Nix width?

Thanks, Tony

Not sure anyone has done that before with RPM rear mounts and long arms. You could think of using 0.125 Custom Works spacers (http://www.ebay.com/itm/NEW-Custom-Works-Rear-Wheel-Spacer-125-2-7208-NIB-/390840622149?hash=item5affea9c45) to get your stock configuration a bit wider in the rear and use these on the front: http://www.ebay.com/itm/Associated-7222-Wide-Front-Axles-2-RC10GT-RC10-Worlds-/301178875470?hash=item461fa8ee4e or experiment with B4 rear hubs and B44 CVDs. You could also try using teh conversion kit AE has released with the re-re Worlds' car: http://www.ebay.com/itm/TEAM-ASSOCIATED-6002-1-10-RC10-WORLDS-CAR-REAR-HUBS-WITH-BEARINGS-/381367716537?hash=item58cb498ab9 and http://www.ebay.com/itm/NEW-TEAM-ASSOCIATED-RC10-WORLDS-EDITION-Axles-Rear-AR4-/311402734616?hash=item48810ca418
Then there is the 3D printed way: http://www.rc10talk.com/viewtopic.php?f=35&t=38327

Thanks for the links, unfortunately I still have the 1/4 inch universals, those spacers won't work with those.

I have spun the idea further, I will also make a narrow nose plate to match the width of the RPM narrow rear. Too bad the B4 is even narrower. Maybe I can get the b4 mounts to fit, they're cheap.