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Old 10-31-2006, 10:01 AM   #16
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I've gone over my building of my car. I've been flying helicopters for around 10 years. One thing us heli guys are known for, is building!!!! If it's not persice, it won't fly. I carry the same tradition over to cars. In fact, i shim every spot on the car. There is no slop anyware. I know cars don't need that type of precision. But, you can't teach an old dog new tricks. As for my motor, I'm not sure what it has in it for springs. It is stock out of the package from stormer hobbys. I have a motor guy. I've never opened up a motor. He turns,zappes,serates, and tunes my motors for me. I build,and balance his wheels and tires for him. A good trade. I know, some of you say that balancing for off road makes no differance. I begg to differ. (I've had this talk before) First of all, you get even ware across the tire. second you gain around 200 rpm rotating. (I made a test stand for this) In helis, unbalanced items rob power, no differant in cars. I get comments at the track all the time, How do you have that torque and all that top end??? Well I can run a lower gear ratio for comming out of the turns, and then I get the top end with the balanced tires give me more rpm. Sorry for ranting, I've been questioned about this before. Funny thing is, most of the guys at the track now balance there tires.
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Old 10-31-2006, 03:45 PM   #17
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You should try some different pinions. I suggest with the komoto going smaller on the motor pinion because it is an rpm motor. You will know when you hit the right gearing as the motor with come alive. I found that I like to use red springs with Reedy 767 brushes. These brushes make more torque than the Trinity E brush (4466) that is commonly used with komodo. Also, remove the motor pinion and see how easy the driveline rolls. One area to watch is the place between the slipper and belt tensionser arm. If there is not enough shims put inbetween the two items they can rub and cause drag.
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Old 10-31-2006, 07:04 PM   #18
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I'll try going down with the pinion. I didn't go down to a 18 tooth. I guess I should have gone further. I'm racing tomorrow night. I was going to do stock buggy. Maybe I'll do 4wd. Thanks for the feedback guys.
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Old 10-31-2006, 08:35 PM   #19
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When I was running the XXX-4 I was using a 11x2 Revolution V2 in mine. I had it geared 19/92 and it would temp at 180 degrees. Make sure you are using the aurora body and have the scoop opened up for proper cooling. If you are still having problems there is a company that makes a cooling fan setup that fits the XXX-4/XXX-S. I will have to find the link.
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Old 11-01-2006, 05:01 PM   #20
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I had the same problem with my XXX4. I changed the Spur gear to 94 and haven't had a problem since. I was running a 19 turn last year when I was learning to drive the darn thing. Any thing less than an 19 and there was no speed at all, anything 19 and over it was to hot. The guys at the LHS told me to go back to the 92 spur when I starting running a brushless and I had the same problem. To big a pinion to hot, go small enough to cool it off and I had no speed. Can't give you any temps, but I can hold my fingers to the motor after a race.
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Old 11-01-2006, 09:33 PM   #21
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Well you guys were right. I dropped to a 17 from the 20 tooth pinion. My temp never got over 174. That is ware I want it.
Thanks Guys
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Old 11-01-2006, 09:37 PM   #22
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Also, how did the motor respond? Did it get more powerful? When you hit the sweet spot gearing wise the motor will come alive.
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Old 11-01-2006, 09:51 PM   #23
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Well Im more confused than before.. I got to the track early tonight for practice so i got some more time to mess with gearing.
Fully dis/equal battery to .9/cell, cool then charge at 6a/30mv
Intel. 1.21 3800s
P2K2
red/purple springs
polished bushings/arm
I run a wrap around the can style Assoc. 12th scale motor heat-sink. the motor can holes are only blocked on 1 side of the can for about a 1/4" on the slot closest to the motor plate, so the air flow isnt a problem and the body is vented properly arond the motor/ESC.
Started the night with the afore mentioned 19/92. 5min 34sec 178`
18/92 5min 28sec 188`
20/92 5min 37sec 186`
21/92 4min 56sec 213`
I was getting alot hotter temps tonight than normal, traction was unreal, my rear diff actually came loose tonight, first time ive ever had that happen.
I pulled it apart checked the arm, cut it,re-brushed it,cleaned it, the regular stuff and put it in the box.. Im stumped

the 21 was AWESOME insane punch out of the turns and a rocket threw the flater sections, but it fell off hard at the 4:50 mark when i pulled it and temped the motor.And 213 sure aint' good

The 20 is what i think im going to run Sunday. Its got a good mix of punch/speed. It seems to fall off right at the 5 min mark so it should be good if im smooth.

The 19 was what i was running but it just gets walked threw the flat sections. The track has alot of turns/jumps but it just didnt seem to have the speed behind it to set-up a few sections like i was able to with the 20.

The 18 just sucked, every where actually. My timing was all off too.. it had crap for reaction.

I have a new 94 i might have to try. Going up with the Spur means i would go up or down wth the pin.???
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Old 11-01-2006, 11:07 PM   #24
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I would try the 20/94 combo. Best way is to look at the ratio. The driveline ratio of the XXX-4 is 2.10 so this means:

19/92= 10.17
20/92= 9.66
21/92= 9.20
20/94= 9.87
21/94= 9.40

See the 20/94 ratio falls between the 19/92 and 20/92, and the 21/94 falls between the 20/92 and 21/92 ratios. Going up two teeth on the spur is like going down a half a tooth on the pinion. Also, you can free up the drivetrain in the XXX-4 more by taking out the belt and cutting off every other tooth on the belt. It will sound bad because of the increased skipping but be very fast. This is a trick that the pros use.
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Old 11-03-2006, 03:50 PM   #25
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Quote:
Originally Posted by sport10
I would try the 20/94 combo. Best way is to look at the ratio. The driveline ratio of the XXX-4 is 2.10 so this means:

19/92= 10.17
20/92= 9.66
21/92= 9.20
20/94= 9.87
21/94= 9.40

See the 20/94 ratio falls between the 19/92 and 20/92, and the 21/94 falls between the 20/92 and 21/92 ratios. Going up two teeth on the spur is like going down a half a tooth on the pinion. Also, you can free up the drivetrain in the XXX-4 more by taking out the belt and cutting off every other tooth on the belt. It will sound bad because of the increased skipping but be very fast. This is a trick that the pros use.
Now what would e a good ratio to stay in? Those number really are just japanese to me..
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Old 11-03-2006, 05:18 PM   #26
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I would give the 20/94 pinion spur combo a try. Do not let the numbers mess with your head. The lower the number the higher the ratio. You said you liked the power of the 21/92 combo but had problems with overheating. By switching to a 21/94 you are just slightly lowering the ratio from 9.20 to 9.40 to keep from overheating. The next step lower would be 9.66 which is acheved with a 20/92 then 9.87 is achieved by using the 20/94 combo. Here is the best way to look at it:

Higher the number the lower the drive ratio: More acceleration, less topend
Lower the number the higher the drive ratio: More topend, less acceleration.

You get the drive ratio by dividing the Spur by the pinion and then multiplying by the ratio of the transmission.
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Old 11-03-2006, 06:47 PM   #27
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I ran XXX-4 until earlier this year. I ran the 5800 brushless with the recommended gear/pinion that the novak recommends 94 spur with either a 20 or 21 pinion depending on the type of track.

Only changes I did was add a fan to the speed control and on the body above the motor instead of just cutting holes I cut the body in a c shape and lifted it up to act as a louver to direct air over the motor.
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Old 11-03-2006, 09:36 PM   #28
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Im going to give that combo a shot.

I was snoopin around since i got my car used i never got the real manual. The XXX4's manual reccomends a 25 and has the same ratio as the G+ manual of 2.10 that reccomends 17-20(depending on track size and motor).

My car started out a regular XXX4, i bought everything but diffs and pulleys/slipper. But the ratios are the same on both models so i wonder why the early version has a 25 and the latter 17-20....
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Old 11-03-2006, 09:37 PM   #29
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Sport..thanks for all the help BTW
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Old 11-06-2006, 07:35 AM   #30
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21/94 it is. Came off at 160` even at 5mins 45sec. batteries and ESC where "room temp"

Thanks for all the help guys
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