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Old 07-10-2009, 06:17 PM   #931
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As mentioned in an email a while back. CRC replaced two of my axles free of charge with the new axles that they just got in. Of course the problem is if you order from any other hobby shop it is a throw of the dice and never know if you will get the older problamtic axle or the new ones. If anyone has problems with the axle and still have a receipt call crc up and send it back for new ones. So far I have had not problems with the new axle.

The other work around was the epoxy which holds well but the problem is that it expands your carbon fiber axle and now you have to sand it down to get the bearing in. I also experienced some cracking doing this procedure so I gave up and sent them back.

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2-wheel-drive-I don't have the hub in hand to measure it. The SS or super speedway car is an intermediate width oval car in between a wide pan and a 200 mm oval car. I don't think the hub will fit normal oval cars like the L2. A IRS wide pan hub is often used as a 200 mm oval cars right hand hub. What car are you putting the hub on and we will go from there.


Gen X 10 rear AXLE PROBLEMS
It seems that the problem of the threaded stud pulling out of the rear Gen X 10 axle is not under control yet until stock is used up. We are outfitting about 17 (out of 22 total) of these cars for our World GT Petite Le Mans Club racing. We had three axles separate this weekend. One of these was a brand new in a package replacement part axle! So what to do.

Here is a rock solid permanent fix that will get you back in action overnight.

First the reason the glue up is not working is probably graphite dust coating the hole. The glue never even wets the actual graphite of the axle. A nice cylindrical plug pulls out with the stud with little effort. It is coated with this black powdery dust. You must clean off this dust. I used alcohol on a Q-tip cotton swab which I narrowed by removing some cotton and then re-rolling it. Clean out the hole. Clean off the cylinders blackness until you can see fairly translucent glue. Don't remove the glue. Drill the little hole, shown in the pic, half way through, with a tiny drill bit. Here is the point of the hole. You will reinstall the stud by putting a nut on it, coating it with glue and hammering it into place gently. The hole will prevent a hydraulic lock situation if you put too much glue. The excess will shoot out of the hole. The hole will also provide a vent to help cure the thin super glue from both ends now. My repair looked good. I removed the couple threads of excess glue with a 8 x 32 TPI die (optional task). Good to go, after an overnight cure.

Super Glue Accelerator (on stud and hole) may reduce curing to 30 minutes. I did not try it. Certainly you must wait to put it on until after the stud is hammered home.

It will be a lot faster repair than ordering a new axle that may or may not be up to the task. I hope this is resolved soon.
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Old 07-10-2009, 08:25 PM   #932
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2 w drive- Ok. Battle Axe right hand hub to make a wide pantoura.

You need a wide pan axle
some wide (red) axle spacers like those from Hyperdrive
Assemble your right side. Add a tire. Measure from the middle of the pod to right hand tire. Best use an inscribed setup board. Good numbers are 110 mm (220 mm wide) al the way to a widest of 117.5 (235 mm wide). You can add a 1/8 or 3/16 inch spacer inside of the diff flange to make this side wider. If you use too many spacers you force yourself into an extended pinion and its related extra wear on the motor bearing.

Now use spacers and your double clamp hub to make the left side the same width.

The battle axe hub is not likely to be exactly the same width as the IRS wide pan right hand hub which can also be used. You can make a good car anywhere in between 220 and 235 mm rear width, though.

Or use the Calandra widening kit if you have a Gen X 10 pod you are working on. One of my cars has this widening adaptor on the right hand hub, but I purchased a wide pan axle and fitted the left side with the much lighter spacers.
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Old 07-11-2009, 01:50 AM   #933
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Quote:
Originally Posted by John Stranahan View Post
2 w drive- Ok. Battle Axe right hand hub to make a wide pantoura.

You need a wide pan axle
some wide (red) axle spacers like those from Hyperdrive
Assemble your right side. Add a tire. Measure from the middle of the pod to right hand tire. Best use an inscribed setup board. Good numbers are 110 mm (220 mm wide) al the way to a widest of 117.5 (235 mm wide). You can add a 1/8 or 3/16 inch spacer inside of the diff flange to make this side wider. If you use too many spacers you force yourself into an extended pinion and its related extra wear on the motor bearing.

Now use spacers and your double clamp hub to make the left side the same width.

The battle axe hub is not likely to be exactly the same width as the IRS wide pan right hand hub which can also be used. You can make a good car anywhere in between 220 and 235 mm rear width, though.

Or use the Calandra widening kit if you have a Gen X 10 pod you are working on. One of my cars has this widening adaptor on the right hand hub, but I purchased a wide pan axle and fitted the left side with the much lighter spacers.
Thanks!
I am not fond of using spacers to get the desired width, i rather use the longer hubs. Specially on the diff side i really don't want the pinion all the way out on the motor shaft. Plus in some way it just doesn't look right as well lol.

I will have to get the IRS long hubs then.

edit:

to be sure, could you measure the battleaxe diff hub? If it is a few milimeters of that is no problem.

Last edited by 2wdrive; 07-11-2009 at 04:28 AM.
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Old 07-11-2009, 05:31 AM   #934
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I prefer long hubs as well. I.R.S makes a 1.25 long left side clamping hub (silver color only). A matching silver wide pan right hub along with just a few spacers will fix you up. I don't have the battle axe hub in hand to measure it.

Pic, left, right side widened with adaptor, wide pan axle, left side using short 3/4 inch red clamping hub and red Hyperdrive spacers. 228 mm

Pic, right, right side wide pan hub, left side 1.25 inch clamping hub (silver only). Just a few spacers to get to 235 mm.
This pod is slightly wider than Gen X 10 so the Gen X 10 will still need a few spacers on the left side.
Attached Thumbnails
CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-gen-x-10-dual-arm-front-end-006.jpg   CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-wide-pan-electrics-install.jpg  
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Old 07-11-2009, 05:39 PM   #935
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JJS Pro Ten

Track test 100F easy Track temp 140F plus

Speaking of a wide Pantoura, this is my edition of the wide Pantoura. I had a long eventful track session with the car as I get it acclimated to the new layout and the new smooth asphalt. I encountered many wide pan car problems.

Soft Front End; Blowovers
During the week the track has been quite dusty and low traction. I softened front and rear springs. The front wire went from .043 with 4.5 coils to a .032 with six coils. The car drove very good during the week. The front end felt putty like. On Saturday we had a full crew of 1/10 Nitros, 1/8th Nitros, 1/8th IGTs and one or 2 other electrics. We had the best local Nitro drivers available. By about 1:30 PM we had put a nice blue groove in the asphalt. Traction was medium with low tire wear. At this point my car was turning into a rocket. Speeds continued to get higher on the straight. Finally I reached a threshold and the car started to blow over; it would just take off in flight 2/3 down the straight. I would guess at 68 mph or so as I was clocking 65 mph mid week with no hint of the problem. What was happening had a twofold cause. One, a crash had bent my front bumper a little and was holding a corner of the body slightly high but only 1-2 mm up. Second the wimpy springs allowed the front end to lift from engine torque and good traction. This was the big culprit. A simple spring change to the stiff mothers and two plastic body posts that let me pull down the nose that extra 1 mm did the trick. The car was unbelievably fast on the straight now. I would gain about 7 feet on a very good 1/10 Nitro with a good driver at the wheel. Plenty of favorable comments from the pits when I finished a heat. When calculated out, I believe my front springs are on the order of 35 lb/in. The mechanical advantage on the lower arm is not that high though as they are quite tilted in. I added one ounce ballast to the front as added insurance when you get in a swarm of cars on the straight.

Gearing
The super cooling afforded by the single scoop had allowed me to play with the gearing. I could now afford to look for the optimum gear rather than the gear that would need to be used just to keep the car from catching fire. I started with a 90/14. What a pleasure this is to use over a 12 tooth. I could use 100% brakes with the M8's anti lock feature turned on. Super quiet. Nice mesh. Not quite enough acceleration in the infield. A little to hard on the lead wires to the motor. I am using 14 gauge as more or less a fusible shunt to the motor. They tend to desolder when amps are too high. It desoldered at about 5-6 minutes.

90/13, Oh my gawd. There was nothing that could touch the car anywhere. I chased down the fastest Nitro 1/10 scale and made up 15 feet in one lap. That was startling enough to cause him to err and allow an easy pass. Speed on the straight was super. Acceleration in the infield was the best ever. I could brake at 100% allowing very fast entry into the mid course turns.

90/12 last. I used this gear exclusively on the old layout. It accelerates well, does not overheat too much, has decent top speed, but if you can cool that 3.5 enough to run one more tooth, it is a real eye opener. 90/12 seemed pathetic after the tests above.

That new front end is working out very well. It is very Robust. Grip is outstanding. I made a small adjustment to roll center by lowering the entire top plate about .020 with shorter pedestals. It is ready for productions. Look for something new in the near future maybe from Doug Powell at PRC who makes the wide pantoura kit for CRCs Pantoura now.
Attached Thumbnails
CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-jjs-pro-ten-setup-new-asphalt.jpg  
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Last edited by John Stranahan; 07-11-2009 at 05:52 PM.
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Old 07-12-2009, 11:09 AM   #936
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A pic i took during a pro10 race that took place as a demonstration class during the touring car nationals some months ago.
Quite interesting with x-ray parts, asso b4 parts and some home made aluminium stuff.


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Old 07-12-2009, 07:10 PM   #937
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Thanks for the pic. Interesting front end. A move in the right direction.



BATTERY C rating

The RC world is abuzz with the c-rating of new LiPos. Some 40 c Packs are now advertised.

I alway thought they were cheating us somehow and not giving all the test parameters when they report a graph showing a discharge at say 40 c. That is equivalent to 212 amp average discharge on some car packs. So how can they cheat us. Well maybe the packs are refrigerated to 32 F before the test. Maybe they are run in an ice bath to control the heat evolved. Could they really have developed earth shaking chemistry in the short period of one year that would allow the pack to be discharged at 28c or 40 c? I think not.

Well the results are in rather slowly for my new SMC 28c 6000 mA-h packs. In theory 28 x 6 gives me my maximum amperage discharge rate that can be tolerated by the battery. I should be able to do a 168 average ampere discharge with the pack.

Here is a pic of the pack. The maximum average discharge over a 6 minute run did approach 50 ampere but the pack is effectively ruined. This is nowhere close to 168 amperes. It was easily 3/4 inch taller at the bend right out of the car. It broke screws in tension failure! I have to conclude that c ratings are cleverly concealed lies by the manufacturers that are only able to be achieve under secret not to be revealed conditions.

I did not start at 32F. We have no refrigerator at the track. I had no ice bath in the car to cool the pack. It started at 100F and ended up 159 F.
Note that I have noticed this pack swelling at 122F. That is pitifully low. This is a considerably lower number than other packs that I have used. The Worley Parsons packs from FMA direct were the best at not overheating. Swelling started at 150 F or so.

Anyway I am pissed off about c ratings that we cannot come anywhere near in the real world. How about a realistic number at a realistic starting temperature with no pack cooling as is the norm in RC racing. I think the guys in Minnesota put their stuff up for the winter or race indoors. Giving us Minnesota winter temperature ratings is not helpful.

As a side note these two packs are working fine in the touring car. It just happens the touring cars are not quite as hooked up wih a rubber tire on this new asphalt as on the previous LATEX surface. I am also demotored slightly to a 4.0 to make a 6 minute run time without overheating the motor.
Attached Thumbnails
CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-smc-28c-6000-ma-h-hard-case-roar-approved-pack-002.jpg  
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Last edited by John Stranahan; 07-12-2009 at 07:31 PM.
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Old 07-12-2009, 07:22 PM   #938
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JJS Pro 10

To say this car is hooked up is an understatement. I had picked an intermediate gear to test an additional cooling feature on the car. 13/90. This reduced top speed from 65 to 58 on the straight. It still accelerated like a bullet. Infield manners were super. laps were very quick. It was easily the fastest car on the track. Guys from the offroad track came to inspect it.

At this gear and 140F track temp, the liminting factor seems to be the battery. I had run a half dozen laps on this pack. Then after a considerable time, I ran a timed 6 minutes. The car got a little soft right at the buzzer. I stopped. Motor temp 190 F. Speed control temp 150F. Pack temp 159F. The lead wires and motor can tabs are now receiving a blast of cooling air from the same cooling vent which I extended rearward. I can probably gear 13/93 and have a good chance at 6 minutes with different brand of battery. I may try the thunder power 5300 mA-h 40c. If you have already located a pack with good heat resistance on high discharge let me know.

Or maybe I just need to run it 5 minutes. What time are you guys in Europe running in mod pan.
Attached Thumbnails
CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-smc-28c-6000-ma-h-hard-case-roar-approved-pack-003.jpg   CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-jjs-pro-10-front-suspension.jpg   CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-wide-pan-custom-3-link-dual-arm.jpg  
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Last edited by John Stranahan; 07-12-2009 at 07:36 PM.
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Old 07-12-2009, 09:04 PM   #939
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John, in your quest to be the fastest onroad asphalt driver on the planet here, why don't you go to a 3s or 4s lipo? Trying to get max performance while routinely pushing 200A through 14ga wires is just silly.
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Old 07-12-2009, 10:34 PM   #940
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Hi John, we run 5 minutes runs.

You're getting in the really fast zone if you get your 5300 mAH pack to dump in 6 minutes .
I can dump my 4900'ers in 5

Just 2 notes on your Lipo experiment:
- Hard-case packs keep the heat in the cell. They don't dissipate heat well as you have noted. I really don't see why we need to have hard-cased battery for safety, especially since the latest cells stay safe even when punctiured.
- Most C-ratings are peak values. Off course they never tell you how long this 40C burst can be sustained. In my opinion, C-rating is no good comparison for packs unless it is backed up by test results.
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Old 07-13-2009, 03:51 AM   #941
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Adamge-It is nice having the fastest car on the track.

I try to keep even my experimental cars in an existing class, in this case 6 cell pan (2s LiPo). I have a least a couple of guys interested in the class now. I will probably have more after say 6 months of world GT when guys want to move up to something different. I will note that they ran an experimental wide pan class in conjuction with the Nationals. That is a good sign of things to come maybe.

There is no 3S LiPo class. In spite of this I have tried higher voltage with a castle Mamba Max speed control. It was a complete failure as the very rugged speed control that is very heat resistant would now thermal at 30 seconds. This was on 4s LiPo. I do have a Tekin speed control coming. I note that the offroad guys use some of these higher voltages with good success. They don't have the traction we do, though.

These c ratings are supposed to be continuous. There is a rating usually double the numbers I quoted called burst rating that would be the maximum draw allowed on the pack even for a brief moment.
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Old 07-13-2009, 04:24 AM   #942
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Quote:
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Adamge-It is nice having the fastest car on the track.

I try to keep even my experimental cars in an existing class, in this case 6 cell pan (2s LiPo). I have a least a couple of guys interested in the class now. I will probably have more after say 6 months of world GT when guys want to move up to something different. I will note that they ran an experimental wide pan class in conjuction with the Nationals. That is a good sign of things to come maybe.

There is no 3S LiPo class. In spite of this I have tried higher voltage with a castle speed control. It was a complete failure as the very rugged speed control that is very heat resistant would now thermal at 30 seconds. This was on 4s LiPo. I do have a Tekin speed control coming. I note that the offroad guys use some of these higher voltages with good success. They don't have the traction we do, though.

These c ratings are supposed to be continuous. There is a rating usually double the numbers I quoted called burst rating that would be the maximum draw allowed on the pack even for a brief moment.
Hi John! You are on the same path as i am for the moment, i am pushing limits with my 4.0 and i dump a 5300 pack in 4.20, i have now throwed that motor away and trying on a 4.5 instead and had increased my runtime to approx 6.30 for a normal track. I have also looked att the mambamax 5700 or the 4600 combo to try 11.1volt, i probably think that is a good combo, i am just trying to optimize my car since i live in sweden and we dont have a compclass for pancars. It is really frustrating to spend so much money on batteries and motors and dont get happy since you now you not reached the sweet spot with your setup.
IŽll probably will test a mamba and 11.1 in my car, i know for sure that thoose motors are not as sensible on gearing as a racespec setup is, would be great with one motor a couple of packs and some different piniongs, like now, two different packs, 5 different motors and totally clueless
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Old 07-13-2009, 03:38 PM   #943
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John.. I just wanted to drop you a note that I personally have really enjoy reading this thread!

At this time my local track is debating switching our worldgt class from 4 cell to 1s lipo. That being said it appears the single cell will not supply enough voltage to keep the receiver running properly.

Has anyone played around with any of the following solutions. If so what have been your results.

1) 2s lipo (Mini-T 180mah) pack with 6v voltage regulator (25g)
2) voltage booster (6g)
3) 2s a123 1100mah receiver battery (81g) 18mm wide (will it fit the genx)

--------
micah
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Old 07-13-2009, 03:57 PM   #944
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Thanks.
I like the voltage booster by Novak the best. It has been used at several tracks already. Give it a try. It will much simplify charging by going completely unoticed.
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Old 07-13-2009, 09:00 PM   #945
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John,

I am new to the pan car world, I bouhgt my Gen X10 a few months ago but just now I am able to run it.

I have read some of the posts specially the one about the lock nut of the diff, I have ordered the blue associated ones.

One thing that I am not understanding is, the gearing and the roll out thing.

I am going to use the car not for competition, but I am going to be running on a proper track, asphalt track.

I am planning to use the tires as they come out of the box, can I do that?

I am going to run a Xerun 120A Esc with a 8.5T motor, it is a combo from Hobbywing.

I would like to have some help on how to calculate the roll out of the car, and one thing that I did not understand untill now, is how do I set the proper roll out? Is it going to depend on the track or motor? What is the point?

I have learn how to calculate it but I did not understand how to use it properly.
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