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Hey all,
I have recently bought some AW 4 gear chassis and most of them are tight. I have tuned many x-traction cars with great success and love tuning them. But, these 4 gears are testing my slot car tuning knowledge(little boogers). Here is what I've done.
*Stripped the whole car.
*smoothed the gears
* check for the armature spin without components in the car(brushes, magnets etc...)
*Checked rear gear mesh. make sure it runs free
*Loosened gear clamp
*lossened rear screw-a little
* Adjusted tabs on the bottom looking for power or lack thereof.
* Polished armature bottom
Any advice would be great or is it time for the sledge-o-matic:jest:
Thanks for the help:thumbsup:
 

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Go through the car front to back, adding components as you go and eliminate any excess friction or dragging, Gear mesh, axle or shaft bind etc, look for anything out of round or with any wobble & correct that. You may have to slightly enlarge some shaft or axle holes, by drilling or lapping. Everything must roll smooth & free with no noticeable drag spots. Also dont overlook the electrical, many cars have loose rivets in shoe hangers that provide poor electircal connection that will kill the pancake style chassis. Another problem is with magnets that are very loose and can hit the arm, you can shim them with paper to tighten them up. After that its time to switch up magnet & arm combos looking for that sweet combo, and then start adjusting com brush tension for max performance.

OH MY GOSH, I have to stop, as this almost sounds like Fray car tuning, and we all know how involved that gets.

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Model Murdering
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As Dave pointed out, the weeble effect is a big issue. If you've been to the circus and seen the clown car driving around with the off center hubs, you'll have the mental picture.

ONCE I'VE OHMED THE ARM, (first things first) I like to work my way backwards from the axle. Dump all the stuffing out and carefully inspect the gear teeth; then methodically add each component back in one at a time... all the while rolling the rear tires across my fingers. Feel for any glitches and WATCH how the gears are riding on the plate.

When I get to the last idler, I leave the comm pit empty and check the whole enchilada as a unit. Then add the brushes and feel for any snaggles, then remove them. Then add the magnets and click the arm through a few rotations.

Obviously if everything checks out, your probably looking at a secondary tuning issue. I have often found that the four gear design can be a bit sensitive to pick up shoe adjustment. Sometimes the slightest correction can make the difference between a dog and a demon.
 

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i gave up

thanx for posing this question. this past winter i spent a whole evening tryin to make a 4gear go. seemed like hours went by and tried many tips n triks. then it hit me. "i can barley make 3 gears go good" so i dismantled it and put all my 4 gear stuff in a box and hid them till next time i wanna try. seems i,m always behind the curve and i read all the hubbub bout the 4 gear but i have a hard time gettin into em.
 

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Racer8nut,

I have experienced the same problems and been through pretty much everything you tried with the same results as you. I have posted the same question in other sections and gotten pretty much the same advice.

I have seen many posts that the 4 Gears are really fast, yet all of mine act like yours and tuning doesn't seem to get me much improvement.

I still think it comes down to the 2 removable idler gears. I have "lapped" the gears repeatedly but there still seems to be a "tighness" to the drive train once they are put in place.

I don't know what else to do. I do not have any old 4-gears and have no other gears than the ones that came in the cars, so I can't even try replacing them with old stuff.

Help!
 

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If all seams well until the two idler gears are installed, could be problem be that the brass clamp is dragging on the idler? Or is the brass clamp causing the arm to bind in the chassis?
 

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Guys if you will and have the means to check the idler gears you will find that many of them are not round, neither the brass or plastic. If you have the spare parts search for the best round gear & try that to see if the speed picks up, these little pancake cars are monsters when you try to tweak everything out of them. Any tightness, out of round, or excess slop will kill your speed, unfortunately the electrical side is just as picky on spring pressure for shoes & brushes.

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If all seams well until the two idler gears are installed, could be problem be that the brass clamp is dragging on the idler? Or is the brass clamp causing the arm to bind in the chassis?
I checked that on all of mine and adjusted the clamps on those that looked like they might cause binding - it didn't help much. I did catch that exact problem on a couple of recent X-tractions and adjusting the clamp made a noticable difference.
 

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Make sure that the screw that holds the back of the gear plate isn't over tightened. That can put a well tuned car into the dog catagory.
 

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I'm suggesting this on the basis you have a dremel tool (preferrably battery powered) and some extra front rims.

What you can do is to first remove the comm magnets, brushes and springs. Reassemble (minus the noted above) and place tires on the rear rims. Then chuck-up a front rim onto your dremel and place a tire on it. Use the dremel to lap your gears (at slow speed at first). The more you lap them, you'll hear the gears slowly improve mesh. This may sound weird, but do some lapping in both directions, as this will improve the mesh. after this lapping those gears should be free enough to hand-spin the rear wheels with little or no resistance.

The put the magnets, brushes and springs back in the car and it should run much better.
 

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Also watch for a little plastic "Burr" on the AW axle crown gear. I've had to file a couple to stop binding from the gear against the inside of the chassis.
 

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D'oh!

I wrote all that blather and forgot the most important part. Thankfully Dave came through with lapping!

I have yet to meet a vintage or modern four-gear that didnt benefit HUGELY from lapping.
 

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Discussion Starter #16
Thanks for all the advice

Hi all,
Thank you for all the great advice. Unfortunatley, I have not been back to work table to tune on these little buggers. I went on Vacay and came back to a house full of water. The line behind the frig busted and sent water all over the house. Had to rip up laminate florring, tear baseboards etc.... It also wicked up the drywall, but we have a restoration crew drying eveything out, So... my slot car tuning and fun is taking a backseat to insurance claims and clean-up. Sux big time... but we have our health, family and a roof over our heads to we get back to normal. When I do...my little one a nd I are going to do some serious playing:wave:
 

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. . . I went on Vacay and came back to a house full of water. The line behind the frig busted and sent water all over the house. Had to rip up laminate florring, tear baseboards etc.... It also wicked up the drywall . . .

:freak: D a n g - sorry to hear that man - That SUCKS!
 

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Discussion Starter #18
Thanks...we have a recovery crew drying out the place and hope to get things rollin as soon as we get te go ahead. Meanwhile, I am going to head to my local track here in daytona Beach with little one and do some slot racing:wave:
 
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