Results 1 to 35 of 35

Thread: revo rebuild

  1. #1
    RC Qualifier
    Join Date
    Dec 2014
    Location
    Adirondacks
    Posts
    282

    revo rebuild

    I have been out of the hobby for quite awhile. I'm rebuilding my revo to 3.3 specs, had short chassis, but hard to find any bodies I like. My question is about a new engine. I had a 3.3 with Picco carb and traxxas pipe with drilled stinger. Ran great. I have a Trinity pipe I will be using(NIB from years ago in my parts box). Go with another 3.3 with Losi carb or go with an O.S. 21TM. I just have fun around my yard,I don't race. What is everybody's opinion?

  2. #2
    Marshal Double G's Avatar
    Join Date
    May 2008
    Posts
    13,502
    I really like my .21TM with THS pipe. Would I do the engine again if I had to? Probably but the $275 bill is a bit hard to swallow. 3.3 with Losi carb and Trinity pipe may be a screamer as well.
    The Super Derecho

  3. #3
    RC Qualifier
    Join Date
    Dec 2014
    Location
    Adirondacks
    Posts
    282
    Thanks Double G for the honest answer. Price is quite a bit. Could buy two 3.3's. Engines have come a long ways since the pro .15's and cast head 2.5's.

  4. #4
    RC Qualifier
    Join Date
    Dec 2014
    Location
    Adirondacks
    Posts
    282
    I went ahead and ordered a 21tm. I was leaning that way. On the short chassis the 3.3 with the old style 3.2 badlands geared 15/36 it would throw it around like a rag doll,wheelies on demand in first. What is a good starting point for gearing on longer chassis. Until I save up for the newer 3.8's hopefully they have less sidewall and foam movement.
    Not much activity on forums anymore,thats to bad. It was always interesting reading about what others where doing with their hobbies.
    Last edited by grizzly03; 09-10-2018 at 03:55 PM.

  5. #5
    RC Qualifier Trentbaby65's Avatar
    Join Date
    Feb 2017
    Posts
    438
    You'll be very happy with the O.S .21TM.
    Great little engine.

  6. #6
    RC Qualifier chops1sc's Avatar
    Join Date
    Jan 2007
    Location
    Sumter, SC
    Posts
    919
    Quote Originally Posted by grizzly03 View Post
    Not much activity on forums anymore,thats to bad. It was always interesting reading about what others where doing with their hobbies.
    I have noticed this too. Facebook groups have stepped in to fill the void. It is not as structured but you can still get good info and advice if you are in the right group. If you are interested, I can send you a link to the group I am in.
    Revo .18TM
    BL Rustler
    Stampede
    HPI Sprint 2

  7. #7
    RC Qualifier
    Join Date
    Dec 2014
    Location
    Adirondacks
    Posts
    282
    Thank you chops. But unfortunately I don't have facebook.

  8. #8
    RC Competitor
    Join Date
    Dec 2017
    Posts
    57
    send the link chops!

  9. #9
    RC Qualifier
    Join Date
    Jan 2007
    Posts
    931
    Great to see this. I just started on a refresh of a Revo Platinum ��
    Cheap, Fast, Reliable. Pick 2.

  10. #10
    RC Qualifier
    Join Date
    Dec 2014
    Location
    Adirondacks
    Posts
    282
    Been taking me awhile to finish. Trying to find a header to fit 21tm and Trinity pipe. Wanted it to look factory installed. Ordered a header from THS. Hope it works. If not, any others with 3 spring mount that will?

  11. #11
    RC Qualifier
    Join Date
    Dec 2014
    Location
    Adirondacks
    Posts
    282
    How it looks right now

    Last edited by grizzly03; 10-25-2018 at 01:53 PM.

  12. #12
    RC Qualifier
    Join Date
    Jan 2007
    Posts
    931
    Pics aren’t showing?
    Cheap, Fast, Reliable. Pick 2.

  13. #13
    RC Qualifier
    Join Date
    Dec 2014
    Location
    Adirondacks
    Posts
    282
    badaml, sorry so far got only one pic. I'll try to get more tonight. I finished it up. Life gets you sidetracked

  14. #14
    RC Qualifier
    Join Date
    Dec 2014
    Location
    Adirondacks
    Posts
    282
    set up:
    O.S. 21tm geared 14-40
    Trinity exhaust, modded header gasket
    VDR kit #2 piston 50wt oil silver front, blue rear-springs LT rockers
    2070 throttle-brake servo
    Tekno axle carriers and wing mount
    rc4wd Mickey Thompson Baja Claws on proline narrow rims-ACNCM 23mm hub set
    Now I need to hurry up and wait till spring to break in motor.

  15. #15
    RC Qualifier
    Join Date
    Dec 2014
    Location
    Adirondacks
    Posts
    282
    Last edited by Double G; 11-12-2018 at 08:47 AM. Reason: trying to display pics

  16. #16
    RC Qualifier
    Join Date
    Dec 2014
    Location
    Adirondacks
    Posts
    282
    pics are showing up on my computer,tried my tablet they are not displayed. What am I doing wrong? I'm using google photos. First time trying to post photos online. Any suggestions?
    Last edited by grizzly03; 11-11-2018 at 11:38 PM.

  17. #17
    Marshal ksb51rl's Avatar
    Join Date
    Nov 2006
    Location
    Northern NJ
    Posts
    20,525
    Where are you storing/hosting them?
    Alt-248 on the number pad =

  18. #18
    Marshal Double G's Avatar
    Join Date
    May 2008
    Posts
    13,502
    You'll need to find a different host for the photos or provide a link to the album after it is set to public.

    I don't know how big the tires you are using, however, 14/40 is very short gearing for the .21TM. I run stock tires, 16/38 (as well as standard gear set in the tranny) and a THS pipe and have no issues pulling wheelies or doing back flips up the side of trees.
    The Super Derecho

  19. #19
    RC Qualifier
    Join Date
    Dec 2014
    Location
    Adirondacks
    Posts
    282
    Last edited by grizzly03; 11-12-2018 at 10:32 AM.

  20. #20
    RC Qualifier
    Join Date
    Dec 2014
    Location
    Adirondacks
    Posts
    282
    Tires are 7" tall,3.8" wide. Standard gear set also. Trying to use what I have. Figured break in engine with lower gearing then gear up as needed. If the tires are to big,should I switch? I liked the original badlands(3.2 size before 3.8's)the new ones seem to be similar size.

  21. #21
    RC Qualifier
    Join Date
    Dec 2014
    Location
    Adirondacks
    Posts
    282
    [IMG]revo2 by , on Flickr[/IMG]

    [IMG]revo3 by , on Flickr[/IMG]
    Are pics showing now?
    Last edited by Double G; 11-13-2018 at 01:15 PM.

  22. #22
    Marshal Double G's Avatar
    Join Date
    May 2008
    Posts
    13,502
    Yep .
    The Super Derecho

  23. #23
    RC Qualifier
    Join Date
    Jan 2007
    Posts
    931
    Very nice!
    Cheap, Fast, Reliable. Pick 2.

  24. #24
    Marshal Double G's Avatar
    Join Date
    May 2008
    Posts
    13,502
    For those tires 14/40 wouldn't hurt. You could always gear up.
    The Super Derecho

  25. #25
    RC Qualifier
    Join Date
    Dec 2014
    Location
    Adirondacks
    Posts
    282
    Thanks badaml I like the way it turned out. I figured I would break engine in with the lower gearing thinking it should be easier on the crank and rod because this engine has a very strong pinch. I'm hoping after about 1/2 gallon it will loosen up, more likely toward 1 gallon mark then start trying going up in gear ratio. These tires are almost as big as the mudslingers and nearly as heavy. Definitely has a monster truck look, except for the wing.

  26. #26
    RC Qualifier
    Join Date
    Dec 2014
    Location
    Adirondacks
    Posts
    282
    It's been a while, I finally started to break-in engine. I put a quart of Traxxas 20% through it. When I try tuning for power,speed it likes to run hot. I get it to where it runs great and hits 30,000rpm, but temps climb to 260F. Richen it back up temp falls, and so does power. Am I over thinking it and the OS21tm still needs more break-in time? I've read it does take some time to "really come alive" and has a strong factory pinch. Or should I start looking at something else? (engine bearings?)

  27. #27
    Marshal Double G's Avatar
    Join Date
    May 2008
    Posts
    13,502
    It'll come alive after 1/2 gallon and the temps will settle down. I was thinking the same thing when I started breaking it in and a few tanks after.
    The Super Derecho

  28. #28
    RC Qualifier
    Join Date
    Dec 2014
    Location
    Adirondacks
    Posts
    282
    Thanks, that makes me feel better.
    Also have a quick question-How do you prime an engine when you have a pull start? Traxxas EZ start was easy, plug exhaust hit button. With pull start I use hose to blow into tank to prime. If i plug exhaust and pull over it takes forever. Is there an easier way?

  29. #29
    Marshal Double G's Avatar
    Join Date
    May 2008
    Posts
    13,502
    I use a foam ear plug to block the exhaust when not in use. After I fill the tank with fuel, I'll give 8-10 pulls on the pull start, remove the plug and after a couple pulls it will fire up.
    The Super Derecho

  30. #30
    RC Qualifier
    Join Date
    Dec 2014
    Location
    Adirondacks
    Posts
    282
    That's a great tip! Simple ingenuity are the best fixes. That would be a lot easier than trying to block with one hand and pull with the other.

  31. #31
    RC poster
    Join Date
    Sep 2019
    Posts
    1
    Greetings, for lovers of speed anything that increases us happy and i hope very soon finish the modification of my engine and i will pass you photos when this is finished.

  32. #32
    RC Qualifier
    Join Date
    Dec 2016
    Location
    N Dakota USA
    Posts
    417
    Quote Originally Posted by CALUCHO View Post
    Greetings, for lovers of speed anything that increases us happy and i hope very soon finish the modification of my engine and i will pass you photos when this is finished.
    Looking forward to some awesome updates.

  33. #33
    RC Qualifier
    Join Date
    Dec 2014
    Location
    Adirondacks
    Posts
    282
    Quote Originally Posted by Double G View Post
    ... It is fast enough and even a little more after I modified the throttle linkage so that the servo doesn't have to push against the throttle return spring to open the carb.
    Asking in this thread cause I don't want to hijack the other thread.

    I'm curious as to your modified throttle linkage. Do you have a picture or details? Thanks.
    Is this something that can be adapted to the Jato?
    Last edited by grizzly03; 09-13-2019 at 06:26 PM. Reason: curious about adaptation

  34. #34
    Marshal Double G's Avatar
    Join Date
    May 2008
    Posts
    13,502
    T-Max linkage and collars.



    Sent from my iPhone using Tapatalk
    The Super Derecho

  35. #35
    RC Qualifier
    Join Date
    Dec 2014
    Location
    Adirondacks
    Posts
    282
    Thanks Double G.
    Copying the T-Maxx compression spring setup is a great idea! Putting all the spring force on the servo brake side direction would speed it up and help servo life. You wouldn't need a higher torque servo to get the performance of this setup. (It worked on the t-maxx with the stock weaker servos). Once the Revo platform came out I never payed attention to the difference.
    I'm going to use this on my jato, just hitting the throttle I can see everything flexing with the factory setup.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •