.

.

Page 3 of 3 FirstFirst 123
Results 31 to 36 of 36

Thread: G12 motor performance drop off

  1. #31
    Join Date
    Jul 2002
    Location
    Madera, CA
    Posts
    52
    Hi Wallbasher, just chatted with Mike... Like his modified guides, nice wt down as low as it goes..
    Anytime with a 6 the chutes are going to have to be short...otherwise the poor thing runs out of revs... Last time I was at Rogers, the chute was too long for sure, never been to Mike's place and no idea how long the main one is... You tried, that's all we can do is try and find the magic bullet...HAHAHA KEEP EM IN THE SLOT

    Funny that no one has said if anything mentioned here has done a damn thing to either help or not...Another reason I don't like to get involved on the sites... Crash
    If you're serious about Slotcars get Cars By Crash

  2. #32
    Join Date
    Mar 2005
    Posts
    544
    Never ran out of revs. Motor just went flat after so many laps. Ran out of things to try.
    Why do I do this to myself?

  3. #33
    Join Date
    Jul 2002
    Location
    Madera, CA
    Posts
    52
    My guess is that it did run out, and began floating the brushes which leads to heat build up, distorting the com, the more they bounce the hotter the com gets, the hotter the com gets the more out of round it gets and the more the brushes bounce hence the drop off.. My friends in ISRA scale racing now tell me the 5T pinions won't last on tracks with long chutes due to over reving and brush wear.. So back to 6/44, 6/45... on tracks with intermediate chute lengths 5/39 might bridge the gap.. I've raced two times now with 5T at our now gone Rhonert Park trackNever thought I'd run an 84,5 arm on a flat track..Oh well, time marches on.. keep em in the slot
    If you're serious about Slotcars get Cars By Crash

  4. #34
    Join Date
    Feb 2005
    Location
    Chesapeake, Va.
    Posts
    799
    jenson, did you ever check the brush overlap? Brush overlap can cause a lot of heat. I run the same PS .540 @ 45 degree arm with Cahozza T5 magnets in Red Fox cans and had an overheating and push start problem. I cured both by removing .005-.010 of brush from the side of the brushs and installing the cut side as the trailing edge of the brush. Doing this doesn't affect the timing only the overlap. I remove the material from the first 1/3 of the contact end of the brush NOT the entire length of the brush. It worked for me maybe it'll help you. You do realize that Proslot measures timing differently? That 45 degree arm is more like 50 degrees. I suggest you go to their site, if you haven't already, and read the tech article on arm timing. I have no problem running 72 pitch 7x42 or 7x43 gears with .700 diameter tires.
    Last edited by Fast Freddie; 07-09-2019 at 10:31 AM.
    I've done so much with so little for so long it seems like I can do anything with nothing at all.

  5. #35
    Join Date
    Sep 2014
    Location
    Auckland, New Zealand
    Posts
    292
    Fast Freddie

    What sort of life do you get with your G12's??

    Crash was saying that he cut comms and re-zapped every race...so that's why he doesn't get the dreaded fade I guess
    listen, study, spy, try, research, invent

  6. #36
    Join Date
    Feb 2005
    Location
    Chesapeake, Va.
    Posts
    799
    swodem, I don't race GP12 a lot anymore, it use to be my favorite wing car class. I raced it in the Mid-Atlantic series for several years. As I recall I would refresh all the motors after every race as needed. By that I mean I would clean and zap the motor, clean the arm and cut the comm., clean and reface the brushes, check spring tension, and replace bushing/bearings if needed. I would do this if I had raced the motor or practiced with it extensively. I would discard any arm with a comm. .180 or less after a fresh cut. I could easily get 6-10 cuts off an arm before I would quit using it. I recently purchased a couple of arms I used in the Flexi Flats and because the high timed arms gave me so much trouble I purchased lower timed arms. They worked very good with no overheating or push start problems, they just needed a better driver.
    I've done so much with so little for so long it seems like I can do anything with nothing at all.

Page 3 of 3 FirstFirst 123

Bookmarks

Posting Permissions

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