Go Back  R/C Tech Forums > General Forums > Electric On-Road
Tamiya F104 Pro! >

Tamiya F104 Pro!

Community
Wiki Posts
Search
Like Tree14Likes

Tamiya F104 Pro!

Thread Tools
 
Search this Thread
 
Old 07-06-2009, 08:34 AM
  #361  
Tech Addict
iTrader: (13)
 
cheROK1212's Avatar
 
Join Date: Mar 2009
Location: Noneyadammy
Posts: 571
Trader Rating: 13 (100%+)
Default

Originally Posted by robk
I did run the car today on an asphalt parking lot track. The rest of the field was F103s of various configurations.

One thing I did notice off the bat was that the car was somewhat sensitive to bumps. There were some cracks in the lot, one specifically in the straight, that did upset the car. Looking at the way the t bar pivots are set up, the 103 is softer front to back than the 104. My car seemed to skip and bounce over stuff more than the other cars. I even went to the soft T bar, but it was still sort of stiff front to back.

The car did turn hard off center. It was a little nervous, even after putting 60K diff oil on the front pins and going to a black front spring. The key will be to find the way to hit the sweet spot between turn in and push and turn in and get loose. Part of this might also be tires.

I wound up driving the car with the throttle more than the steering wheel. It seemed to take a bit more throttle modulation than I was used to.

Overall, pretty good. Right now I'm not sure if tires would be a big help or not. It is tougher to drive than the 103. This week I might be able to try it on carpet, maybe that will be it's forte.
Hey Rob, will the 3.5 offset knuckles fit and do you think they would settle some of the twitch. Also is caster adjustable and had you done the mod Alfie described?
cheROK1212 is offline  
Old 07-06-2009, 09:31 AM
  #362  
Tech Addict
iTrader: (2)
 
Vyger's Avatar
 
Join Date: Sep 2008
Location: Jackson, Mississippi
Posts: 550
Trader Rating: 2 (100%+)
Default

OK, I switched the servo saver from the longer one to the shorter one and this really helped reduce the bump steer in the front the of the car, allot. I’m using a 9602 servo and mounted per the instructions, 30mm to the center of the servo horn. I didn’t use anything to shim it up. It mounted tight with the kit servo mounts and double sided tape.

I went to our local track this weekend and actually got to see a couple of the F104’s in motion. Everyone seems to be running the box stock set up. One person was running soft springs (silvers) in the front of the car to get more steering. But I never got the opportunity to see him run. On the kit car the rear of the rear seemed to chatter a bit exiting turns but I think that’s set up. A softer T-plate might fix that. I didn’t feel the person’s diff; it may have been too tight.
Vyger is offline  
Old 07-06-2009, 12:39 PM
  #363  
Tech Champion
iTrader: (22)
 
robk's Avatar
 
Join Date: Aug 2001
Location: Macho Business Donkey Wrestler
Posts: 8,201
Trader Rating: 22 (100%+)
Default

Originally Posted by cheROK1212
Hey Rob, will the 3.5 offset knuckles fit and do you think they would settle some of the twitch. Also is caster adjustable and had you done the mod Alfie described?
The offset knuckles should fit, since the kit knuckles are the same as the 103. it should help calm things down. Caster is not adjustable, just camber (at least as far as i know, I didn't measure the caster).

I am going to try the Alfie setup as soon as I can.
robk is offline  
Old 07-06-2009, 12:58 PM
  #364  
Tech Regular
 
alan1467's Avatar
 
Join Date: Dec 2002
Location: Durham UK
Posts: 352
Default

anyone have the part number for the offset knuckles?

Thanks
alan1467 is offline  
Old 07-06-2009, 01:13 PM
  #365  
Tech Addict
iTrader: (2)
 
Vyger's Avatar
 
Join Date: Sep 2008
Location: Jackson, Mississippi
Posts: 550
Trader Rating: 2 (100%+)
Default

Originally Posted by alan1467
anyone have the part number for the offset knuckles?

Thanks
I think this is it.

53259 RC F1 3.5mm Offset Upright
Vyger is offline  
Old 07-06-2009, 01:23 PM
  #366  
Tech Addict
iTrader: (2)
 
Vyger's Avatar
 
Join Date: Sep 2008
Location: Jackson, Mississippi
Posts: 550
Trader Rating: 2 (100%+)
Default

Here's the F104 set up sheet incase anyone needs one or wants to post their set up.
Attached Files
File Type: pdf
f104pro_blank.pdf (427.7 KB, 310 views)
Vyger is offline  
Old 07-06-2009, 03:30 PM
  #367  
Tech Regular
 
dsyed1's Avatar
 
Join Date: May 2009
Location: Washington, DC
Posts: 341
Default

just finished building my 104... nice build... was able to fit a trakpower 4900 lipo with some modifications.. will post pics soon...

just wondering for those who are using lipo's instead of nimh did you end up adding more weight to compensate the lighter lipo? because right now the rear seems a little loose during acceleration from slow speed.. i have also changed the position of the rear wing to create more downforce but i have yet to test that setting
dsyed1 is offline  
Old 07-06-2009, 04:42 PM
  #368  
Tech Elite
iTrader: (17)
 
Alfie's Avatar
 
Join Date: Sep 2001
Location: Singapore
Posts: 2,415
Trader Rating: 17 (100%+)
Default

The offset knuckles fit nicely into the setup. It will definitely solve all the twitch in the F104. The stock knuckles are a little unpredictable.

Currently, I have mounted everything on and have tested the servo (to clear the arms) and motor to run smoothly. One thing I don't like is that the diff section vibrates when you throttle up. It's due to the new adaptor at the end of the diff housing. It's loose. Anyone has a remedy for it?

I'm thinking of using the F103 tires on the F104 wheels, by pushing them into the wheels. Anyone has done this? I'm hoping that the tires don't crack due to tight fitting. I want to make my F104 work with my new foams right from the start.

Alfie
Alfie is offline  
Old 07-06-2009, 06:03 PM
  #369  
Tech Elite
iTrader: (17)
 
Alfie's Avatar
 
Join Date: Sep 2001
Location: Singapore
Posts: 2,415
Trader Rating: 17 (100%+)
Default

The "soft" T-Bar offered by Tamiya as a Hopup is better than those of the stock piece, as the material of the stock piece gets disintegrated over a short period of runtime.

From the F104 design of the T-Bar section, it's meant to be hard. If you put the F103 and F104 side-by-side, you will see that the F103's T-bar goes all the way to the 1st battery compartment piece, hence making it softer. Those 3rd party made those FRP plates to replace those of the Tamiya T-bars because of this issue: the Tamiya T-bar couldn't handle the speed and abuse racers gave to it.

For my F103, I'm using those Kawada T-Bars. Have used the Tech Racing ones before; they broke on me in 30 secs out on the track, after I mounted them on.

If you have the FRP piece mounted, you will also want to get that Aluminum Pivot piece to make it work. Sometimes when the rear starts to chatter or react strangely, I will change the O Ring for a foam padding to dampen the rear end. It's one of those things that is not in the book, but it works.

Alfie



Originally Posted by robk
One thing I did notice off the bat was that the car was somewhat sensitive to bumps. There were some cracks in the lot, one specifically in the straight, that did upset the car. Looking at the way the t bar pivots are set up, the 103 is softer front to back than the 104. My car seemed to skip and bounce over stuff more than the other cars. I even went to the soft T bar, but it was still sort of stiff front to back.

The car did turn hard off center. It was a little nervous, even after putting 60K diff oil on the front pins and going to a black front spring. The key will be to find the way to hit the sweet spot between turn in and push and turn in and get loose. Part of this might also be tires.
Alfie is offline  
Old 07-06-2009, 08:03 PM
  #370  
Tech Elite
iTrader: (17)
 
Alfie's Avatar
 
Join Date: Sep 2001
Location: Singapore
Posts: 2,415
Trader Rating: 17 (100%+)
Default

Hi!

What did you do to the plastic parts to allow the Trakpower to fit into that space?

Alfie


Originally Posted by dsyed1
just finished building my 104... nice build... was able to fit a trakpower 4900 lipo with some modifications.. will post pics soon...

just wondering for those who are using lipo's instead of nimh did you end up adding more weight to compensate the lighter lipo? because right now the rear seems a little loose during acceleration from slow speed.. i have also changed the position of the rear wing to create more downforce but i have yet to test that setting
Alfie is offline  
Old 07-06-2009, 08:39 PM
  #371  
Tech Champion
iTrader: (22)
 
robk's Avatar
 
Join Date: Aug 2001
Location: Macho Business Donkey Wrestler
Posts: 8,201
Trader Rating: 22 (100%+)
Default

Originally Posted by Alfie
The "soft" T-Bar offered by Tamiya as a Hopup is better than those of the stock piece, as the material of the stock piece gets disintegrated over a short period of runtime.

From the F104 design of the T-Bar section, it's meant to be hard. If you put the F103 and F104 side-by-side, you will see that the F103's T-bar goes all the way to the 1st battery compartment piece, hence making it softer. Those 3rd party made those FRP plates to replace those of the Tamiya T-bars because of this issue: the Tamiya T-bar couldn't handle the speed and abuse racers gave to it.

For my F103, I'm using those Kawada T-Bars. Have used the Tech Racing ones before; they broke on me in 30 secs out on the track, after I mounted them on.

If you have the FRP piece mounted, you will also want to get that Aluminum Pivot piece to make it work. Sometimes when the rear starts to chatter or react strangely, I will change the O Ring for a foam padding to dampen the rear end. It's one of those things that is not in the book, but it works.

Alfie
I usually throw the 103 t bars out every 3-4 weeks. Usually, if the car sucks for no apparent reason, i find a new t bar fixes this magically.

As far as the 104 t bar, i think they went a little too stiff. When I was building the car I noticed it was pretty stiff. I don't think there is enough articulation if the surface is not smooth.

I do have the aluminum pivot. The car was not chattering, but actually skipping around over bumps. It felt very light, and it moved around a lot over the bumps. It didn't feel like it was a dampening thing, more like too stiff front-to-back, even with a pretty loose side-to-side setting for the o ring.
robk is offline  
Old 07-06-2009, 10:31 PM
  #372  
Tech Elite
iTrader: (17)
 
Alfie's Avatar
 
Join Date: Sep 2001
Location: Singapore
Posts: 2,415
Trader Rating: 17 (100%+)
Default

I'm going to try the car this weekend to see how it runs. It's also a chance to see what I can tweak on this F104.

That was the reason why I didn't use the carbon shaft on the rear driveshaft. It's simply too light, attributed by the use of Lipo these days. So I needed all the weight I can find. I even added some lead weights on the left to compensate for the heavy diff on the right.

Just don't worry too much of the T-bar. Make sure your diff is working correctly should do the trick. My current F103 was twitching a lot left to right after I changed the front arms, so I suspected that it could be the crack in the T-Bar. Will change it for this weekend.

Are you using Lipo? You may want to add some dead weights on your F104.
Alfie


Originally Posted by robk
I usually throw the 103 t bars out every 3-4 weeks. Usually, if the car sucks for no apparent reason, i find a new t bar fixes this magically.

As far as the 104 t bar, i think they went a little too stiff. When I was building the car I noticed it was pretty stiff. I don't think there is enough articulation if the surface is not smooth.

I do have the aluminum pivot. The car was not chattering, but actually skipping around over bumps. It felt very light, and it moved around a lot over the bumps. It didn't feel like it was a dampening thing, more like too stiff front-to-back, even with a pretty loose side-to-side setting for the o ring.
Alfie is offline  
Old 07-07-2009, 12:36 AM
  #373  
Tech Regular
 
alan1467's Avatar
 
Join Date: Dec 2002
Location: Durham UK
Posts: 352
Default

Anyone tried the F103 front spring kit 50509 on their F104?
alan1467 is offline  
Old 07-07-2009, 04:39 PM
  #374  
Tech Elite
iTrader: (17)
 
Alfie's Avatar
 
Join Date: Sep 2001
Location: Singapore
Posts: 2,415
Trader Rating: 17 (100%+)
Default

Hi guys,

I have just managed to break the rules by squeezing the F103 tires onto the F104 wheels. It's only the front ones that I did.

It may look a little off the scale, but the ultimate reason for doing so is to use the already-proven tires on my F103 onto the new F104.

Can't wait to try it.
Alfie
Alfie is offline  
Old 07-07-2009, 04:42 PM
  #375  
Tech Elite
iTrader: (17)
 
Alfie's Avatar
 
Join Date: Sep 2001
Location: Singapore
Posts: 2,415
Trader Rating: 17 (100%+)
Default

You may want to try the Kawada springs (meant for their 1/12 pan cars). They were produced towards the same concept as the F103 in mind. I used them on my F103GT before and they were good. Tamiya springs aren't quite different from each spring rate, but only the black ones slightly harder. Improves steering.
Alfie



Originally Posted by alan1467
Anyone tried the F103 front spring kit 50509 on their F104?
Alfie is offline  


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.