R/C Tech Forums

Go Back   R/C Tech Forums > General Forums > Electric On-Road

Reply
 
Thread Tools Search this Thread
Old 08-06-2009, 06:41 PM   #1786
Tech Master
 
Join Date: Jan 2006
Location: Kansas City, MO
Posts: 1,259
Trader Rating: 13 (100%+)
Send a message via AIM to HenBeav
Default

Quote:
Originally Posted by syndr0me View Post
Yeah, but then you wouldn't get to experience the Kansas Rectangle. See you in 30 years.
But flying would have cost the same, at least now for dustin after our small detour to the shoulder
__________________
[URL]http://www.fastlanehobby.com[/URL]

Support your local Lowe's, Walmart and Layne Machine Works INC.
HenBeav is offline   Reply With Quote
Old 08-06-2009, 08:10 PM   #1787
Tech Master
 
jkirkwood's Avatar
 
Join Date: Feb 2007
Posts: 1,224
Trader Rating: 8 (100%+)
Default

anyone know the release date on the foam spec kit?
jkirkwood is offline   Reply With Quote
Old 08-07-2009, 02:08 AM   #1788
Tech Apprentice
 
Join Date: Nov 2004
Posts: 82
Default rear cvd

Hi

Yesterday I was testing with my photon, I tried to make the rear as narrow as possible, but when I took out all the shims and just leave in the rear 1.6mm the blade of the right side stops against the diff, shall I modify something?

Thank you in advance
__________________
RC Racing addict
Roedor is offline   Reply With Quote
Old 08-07-2009, 03:35 AM   #1789
Tech Champion
 
CraigM's Avatar
 
Join Date: Mar 2007
Location: Sydney, Australia
Posts: 7,009
Trader Rating: 34 (100%+)
Default

Quote:
Originally Posted by Roedor View Post
Hi

Yesterday I was testing with my photon, I tried to make the rear as narrow as possible, but when I took out all the shims and just leave in the rear 1.6mm the blade of the right side stops against the diff, shall I modify something?

Thank you in advance
searching can sometimes be fun, but in lieu of that TOP make a 43mm dogbone and tamiya a 44

that's pretty narrow at the rear by the way
__________________
www.facebook.com/mcpheerc
CraigM is offline   Reply With Quote
Old 08-07-2009, 03:40 AM   #1790
Tech Adept
 
amnesia's Avatar
 
Join Date: Jul 2009
Location: Bournemouth, UK
Posts: 119
Default

The kit I bought last week in the UK had an amendment sheet that says (in my own words)...

If running the rear arms with a lot of toe in, or a lot of camber then reduce the number of washers in the diff from 6 to 4 to prevent the end of the dogbone contacting the diff components. Alternatively, TOP produce a 43.5mm dogbone which will solve the problem.




Would using narrower hubs, or different offset wheels achieve the same thing ?

The standard hex-hubs are 5.2mm IIRC... 4mm ones would give a net effect of reducing rear track by 2.4mm. Not sure how (if) this would be different from moving the suspension pivot points inboard though.

Daniel.
amnesia is offline   Reply With Quote
Old 08-07-2009, 03:48 AM   #1791
Tech Champion
 
danjoy25's Avatar
R/C Tech Charter Subscriber
 
Join Date: Oct 2003
Posts: 5,135
Trader Rating: 37 (100%+)
Default

Quote:
Originally Posted by amnesia View Post


Would using narrower hubs, or different offset wheels achieve the same thing ?
Nope, your still using the same length dogbones and will still hit the diff screw.
__________________
Awesomatix A800 & A800X/ Mugen MTX-5 / 3 Racing F113 / Kyosho RB5 / Kyosho Mini-Z
danjoy25 is offline   Reply With Quote
Old 08-07-2009, 03:51 AM   #1792
Tech Adept
 
amnesia's Avatar
 
Join Date: Jul 2009
Location: Bournemouth, UK
Posts: 119
Default

Quote:
Originally Posted by danjoy25 View Post
Nope, your still using the same length dogbones and will still hit the diff screw.
You are, but you will still have the shims in the suspension mounts. In effect, all this does is move the wheel closer to the hub, not alter the length or geometry of the suspension arms.
amnesia is offline   Reply With Quote
Old 08-07-2009, 08:36 AM   #1793
Regional Moderator
 
mrrcguy's Avatar
 
Join Date: Mar 2007
Location: Jonesboro Akansas
Posts: 3,157
Trader Rating: 25 (100%+)
Default

Quote:
Originally Posted by amnesia View Post

The standard hex-hubs are 5.2mm IIRC... 4mm ones would give a net effect of reducing rear track by 2.4mm. Not sure how (if) this would be different from moving the suspension pivot points inboard though.

Daniel.
This is a good one I would like to get some feedback on.

What will be the likely result when changing width with wheel spacers and wider hexes rather than doing it inboard at the bulkheads?

Josh? Josh?


Uh,,,,,,,,,, Josh?

Tell me now before I get angry!!!
mrrcguy is offline   Reply With Quote
Old 08-07-2009, 09:05 AM   #1794
Tech Master
 
timmay70's Avatar
 
Join Date: Dec 2003
Posts: 1,702
Trader Rating: 5 (100%+)
Default

Shimming at the bulkheads vs. shimming at the wheels will affect the roll centers...
__________________
Speed Merchant Rev7, Tekin, TQ Racing (wire), Team Tamale
RC Excitement - Buy where you race, support your local tracks.
ROAR #105242
timmay70 is offline   Reply With Quote
Old 08-07-2009, 09:09 AM   #1795
Tech Master
 
Join Date: Mar 2003
Posts: 1,462
Trader Rating: 2 (100%+)
Send a message via AIM to goop
Default

shimming at the bulkhead will change the angle of your shock and also the leverage point, along with a longer camber link. i have found that this actually will make the car smoother and more stable. i have always been told if you can widen a car do it at the bulkheads, or if narrowing the car take away from the hexs or spacers to a point.
__________________
Hurricane Motorsports
Team Trinity

TOP Racing - Gravity Rc - Contact tires - KO Propo - Competition Electronics
goop is offline   Reply With Quote
Old 08-07-2009, 09:29 AM   #1796
Tech Master
 
Join Date: Jul 2004
Location: MI
Posts: 1,544
Trader Rating: 1 (100%+)
Send a message via AIM to John St.Amant Send a message via MSN to John St.Amant Send a message via Yahoo to John St.Amant
Default

Quote:
Originally Posted by mrrcguy View Post
This is a good one I would like to get some feedback on.

What will be the likely result when changing width with wheel spacers and wider hexes rather than doing it inboard at the bulkheads?

Josh? Josh?


Uh,,,,,,,,,, Josh?

Tell me now before I get angry!!!
Adding shim at the wheel makes the car wider and more stable but does not affect the suspension as much as making the inner hinge pin farther out. That in fact changes the lower shock position and the roll center.
Big difference.
__________________
Pro-Line Racing , Boca Bearings , Competition Heat.
Team Durango DEX210, DEX410V3, DESC410R, DNX408
Futaba FAAST 2.4 4PkS, LRP, Tekin, Xcellorin

Last edited by John St.Amant; 08-09-2009 at 06:18 AM.
John St.Amant is offline   Reply With Quote
Old 08-07-2009, 01:53 PM   #1797
Tech Adept
 
Thirtybird's Avatar
 
Join Date: Jan 2009
Location: Metrot Detroit, MI
Posts: 233
Trader Rating: 6 (100%+)
Default

Quote:
Originally Posted by amnesia View Post
The kit I bought last week in the UK had an amendment sheet that says (in my own words)...

If running the rear arms with a lot of toe in, or a lot of camber then reduce the number of washers in the diff from 6 to 4 to prevent the end of the dogbone contacting the diff components. Alternatively, TOP produce a 43.5mm dogbone which will solve the problem.




Would using narrower hubs, or different offset wheels achieve the same thing ?

The standard hex-hubs are 5.2mm IIRC... 4mm ones would give a net effect of reducing rear track by 2.4mm. Not sure how (if) this would be different from moving the suspension pivot points inboard though.

Daniel.
You can remove some of the spring cone washers for sure, but the length of the screw can be an issue too, and if your screw is protruding past your diff nut, you may want to grind the end down a little bit.

shorter swingshafts are a good option to have handy regardless of what you want to do with the shims. I keep a set of 44mm Tamiya swingshafts in my Photon box (since I had them) as a just-in-case.
__________________
Racing a Kawada SV-10 in 2010
http://omgitsakawada.blogspot.com/

The VTA Photon! (Inactive - back to the Kawada!)
http://vtaphoton.blogspot.com/
Thirtybird is offline   Reply With Quote
Old 08-07-2009, 08:26 PM   #1798
Tech Master
 
Josh Cyrul's Avatar
 
Join Date: Sep 2003
Location: Farmington Hills, Michigan
Posts: 1,406
Default

Wow... You guys are killing me.....

Changing the spacers inside/outside does not change leverage... The shock position is the shock position on the suspension arm (point of instance). It will change the shock angle to the tower....

Shims at the bulkhead w/narrow hex - Slightly longer camber link, slightly increased shock angle and outer hinge pin position closer to center line/contact patch of the tire - Usually generates less contact patch/tire scrub which allows the rear tires to work easier and generate more grip. The car will be smoother, more rear traction (especially in the center of the corner) and the rear tires should overheat less in high temp or high load conditions.

Less shims at the bulkhead w/wide hex or shims - Of course, opposite as above. Makes the car more aggressive and loads the tire contact patch harder which can make the car over rotate in the center of the corner.

There's always a balance to this to generate steering vs rear grip. In 1/8 gas racing it can make a huge difference to the rear tire wear. I personally always try to run as narrow rear hexes as possible and then try to make the car steer. If it won't steer, wider rear hexes are a last resort.
__________________
Trinity, Destiny, Ko Propo, Hobby Wing, Ulti Racing Tires, Protoform, Zenon Racing, Pivothead, Vizon, TQ Wire & Hella Graphics
Josh Cyrul is offline   Reply With Quote
Old 08-09-2009, 12:16 AM   #1799
Tech Champion
 
CraigM's Avatar
 
Join Date: Mar 2007
Location: Sydney, Australia
Posts: 7,009
Trader Rating: 34 (100%+)
Default

Quote:
Originally Posted by Josh Cyrul View Post
If it won't steer, wider rear hexes are a last resort.
Are TOP planning some thinner hexes? I tried tamiya 4mm hexes but the pin doesn't sit as deep as it does in the kit ones so you need to shim them a lot to take up the play, in doing so you lose half of the millimeter you saved
__________________
www.facebook.com/mcpheerc
CraigM is offline   Reply With Quote
Old 08-09-2009, 08:45 AM   #1800
Tech Master
 
Josh Cyrul's Avatar
 
Join Date: Sep 2003
Location: Farmington Hills, Michigan
Posts: 1,406
Default

CraigM - I've requested them mainly because of the difference in off-sets between all the rims. If you measure between the TOP or Tamiya rims, they will make the car the most narrow but as you work through different rims and especially into the foam tire rims I found that you would need as narrow as a 4-3.5mm hex to keep the overall width the same. Of course in the rear this is ok but in the front it can create some clearance issues with the rim spokes on the suspension arm. I think they will make a 4mm hex at some point but I think that will wait until we are 100% that there won't be a clearance issue...
__________________
Trinity, Destiny, Ko Propo, Hobby Wing, Ulti Racing Tires, Protoform, Zenon Racing, Pivothead, Vizon, TQ Wire & Hella Graphics
Josh Cyrul is offline   Reply With Quote
Reply



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off



All times are GMT -7. It is currently 04:22 AM.


Powered By: vBulletin v3.9.2.1
Privacy Policy | Terms of Use | Advertise Content © 2001-2011 RCTech.net

SEO by vBSEO 3.5.0