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Old 04-11-2013, 04:12 AM
  #466  
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Thanks guys! i'm going to throw that battery away and do some research.
The esc still works, been parking lot racing sunday evenings car is doing pretty good, using 7 cell NIMH batteries but i hear the lipo's are the way to go.

Broke a second rear belt so it's time for the rear tensioner mod, i ordered it and it came yesterday, still waiting on the kevlar belts to arrive, Found a bit of debris lodged in the front belt pulley that could have caused it (parking lot racing is dirty for the car) have a friend from georgia coming to join the parking lot fun one evening while he is in town so i have to be ready

EDIT: found the tensioner mod on first page and printed it out, i know what i will be doing this evening after work

Last edited by MaxThrottle; 04-11-2013 at 04:33 AM.
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Old 04-11-2013, 08:18 AM
  #467  
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Max, be careful of how you dispose of that battery. It is still a fire hazard. If you have a Batteries+ where you live, they can recycle them safely for you. Otherwise, check with your local waste disposal facility.
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Old 04-11-2013, 12:12 PM
  #468  
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Originally Posted by MaxThrottle
Thanks guys! i'm going to throw that battery away and do some research.
The esc still works, been parking lot racing sunday evenings car is doing pretty good, using 7 cell NIMH batteries but i hear the lipo's are the way to go.

Broke a second rear belt so it's time for the rear tensioner mod, i ordered it and it came yesterday, still waiting on the kevlar belts to arrive, Found a bit of debris lodged in the front belt pulley that could have caused it (parking lot racing is dirty for the car) have a friend from georgia coming to join the parking lot fun one evening while he is in town so i have to be ready

EDIT: found the tensioner mod on first page and printed it out, i know what i will be doing this evening after work

Some people have placed duct tape, screen (to keep the air flow to motor), etc over the major holes in the chassis to keep the debris and rocks out =

This chassis belongs to digitalsmithy, a Chicago drifter
HPI Sprint 2 Mods-rc_5_zps7397f05f-copy.jpg

I may go the screen route for my asphalt chassis -
But I'll probably over engineer some silly way to hold the screen in place with a brass framing instead of shoe goo & duct tape...

Keep an eye on your pulley teeth Max=
If they get tore up it could cause slippage and will tear up new belts
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Old 04-12-2013, 04:07 AM
  #469  
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thanks guys!
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Old 04-12-2013, 07:25 AM
  #470  
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There are two things to consider on the handling of debris on the Sprint 2 chassis:

1. Open the chassis on the bottom and make sure nothing can get trapped easily. The original chassis was closed off and had shields around the belts and pulleys at the diffs. People started cutting their chassis out below the diffs to allow debris to fall through. HPI recognized this and later shipped new units with the areas cut out below the diffs and removed the shrouds from the mounting blocks.

2. Block off access to the pulley areas so debris can't get there in the first place. I think this is harder to pull off but can be done. The main issue here is that the front tires kick stuff up into the chassis, especially while cornering. I believe blocking the debris is best done from the top rather than the bottom. There is a post here illustrating a mod or two for this somewhere.

I've had stuff stick to some cogs in the diff pulley and cause some strange vibrations at certain speeds. Once removed, all was fine and no damage to the belt occurred. Check them frequently and run your car on a stand to listen for the not so visually obvious.

I bought a used Sprint 2 Flux and it has the older block design with the shrouds. A pebble had lodged in the shroud and chewed the rear belt. The seller was kind enough to supply a replacement belt with the unit. I got my Dremel out and removed the shroud on that side as well as the front. I don't think that will happen again. I replaced the chassis with an Exotek which will easily allow debris to fall through. It also helps with weight, tweak and flex. More on this in another post.
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Old 04-13-2013, 04:22 AM
  #471  
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With running in parking lots i need to come up with some sort of inner fender wells
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Old 04-15-2013, 04:43 AM
  #472  
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Belt tensioner mod is done, still waiting for the kevlar belts so i used another hpi belt
Attached Thumbnails HPI Sprint 2 Mods-tensioner1.jpg  
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Old 04-15-2013, 08:34 AM
  #473  
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Looks good max!

When I went to a 66 spur (smallest you can use - I think - without creating issues) for Westgate =
My motor hits the left mount and the rear belt hits the motor =
So I scratch built another rear tensioner -
Using 1/4"x1/4" aluminum bar -
Reversed the mounting position so it comes up from the bottom =
Raising the belt from the bottom pulls it off the motor without over tightening the belt tension...

Also made the bar it self a tad longer (personal preference)

HPI Sprint 2 Mods-dscn4687.jpg


Last edited by Marv; 04-22-2013 at 10:54 AM.
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Old 04-18-2013, 09:58 AM
  #474  
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Questions?? SWAY BARS?

Has anyone done sway bars on their Sprint?
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Old 04-18-2013, 10:52 AM
  #475  
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Me and the guys next door have been racing our Short Course trucks in the parking lot, with a few jumps on the course.

NOW they're talking about getting some onroad cars so their rc's don't get so beat up.

They are looking at the HPI Sprint 2 Flux RTR, but the first review of it I saw wasn't so great.

Is the Ofna JL10e a better car for newbie road drivers, OR ???
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Old 04-18-2013, 11:51 AM
  #476  
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Originally Posted by rcManny
Me and the guys next door have been racing our Short Course trucks in the parking lot, with a few jumps on the course.

NOW they're talking about getting some onroad cars so their rc's don't get so beat up.

They are looking at the HPI Sprint 2 Flux RTR, but the first review of it I saw wasn't so great.

Is the Ofna JL10e a better car for newbie road drivers, OR ???

Difficult to say =
I don't own an Ofna JL10e


You'll have to cut & paste the url's =
The link thingee isn't working again...

OLD POST / SAME QUESTION =

http://www.rctech.net/forum/electric-road/462383-ofna-jl10e-vs-hpi-sprint-drift-2-flux.html

Hardly any Ofna JL10e posts on R/C Tech =
Not too popular on here - - -

http://www.rctech.net/forum/electric-road/316027-ofna-jl-10-e.html

$350 for a Flux and close to the same after you outfit the Ofna with what it needs -

BUT with the Ofna at $120 you'll be able to pick which electronics you want -

Spend more / spend less -
My guess is more...

Tough call -

My S2 has survived almost 33 indoor races + the qualifiers on a very tight track environment =

EXAMPLE:

+ YouTube Video
ERROR: If you can see this, then YouTube is down or you don't have Flash installed.


Usually the course is more "technical" than in the above video -

There's carnage most race nights -

If another driver hits my S2 hard enough (and they have) he's usually wrenching between races, not me...

So far I've only spit wheel and a dog bone when the nylon lock in the axle nut gave out and one hit to the LR wheel popped the camber link ball cup off the ball stud (since upgraded to RPM ball cups and aluminum rear hubs) -

Thanks for the headzup on that Ofna =
People are always looking for cheap beaters to pound into the asphalt -
Not many retail sellers on the net (?)


Last edited by Marv; 04-18-2013 at 03:34 PM.
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Old 04-21-2013, 07:23 PM
  #477  
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Originally Posted by MaxThrottle
Belt tensioner mod is done, still waiting for the kevlar belts so i used another hpi belt

If you come from underneath withe the rear tensioner =
It'll keep the belt from dragging on the motor -
ALSO - DON'T over tighten the belts =


FROM ANOTHER SITE:
briareos2.16.12, 6:45 pm
Actually, belts that are too tight will cause their own set of problems, just as bad as running in pebbly or very dirty areas.

As a rule, you want 4-5mm of "play" in a long belt (typically those on TC chassis), and 3-4mm in the short belt. Those are base settings for any belt drive. Making the belt adjustment too tight will also cause them to wear out much sooner.
The tighter the belts are, makes power "torquey," but makes the motor heat up, and loose belts let the motor rev faster, and cooler.

On Ofna's JL10e Drift, both belts are the same length, so you will use the long belt setting for both.

The best thing for belt drives is to use them in "clean" areas.

All I use for drift are belt drives, and I have yet to replace a belt on any of them, and the oldest is four years old (the first production run Tamiya TA05 VDF).
Additionally, after I saw what 106 heat did to my OEM urethane belts =
I always loosen my tensioners now after using the car to relieve the stress on the belts and cut down on unnecessary stretch...

Last edited by Marv; 06-26-2014 at 08:08 AM.
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Old 04-22-2013, 05:49 AM
  #478  
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So i was going to meet the guys to run in the parking lot last night and was charging batteries and swapping some wheels and put a battery in to check everything and everything worked but the motor, esc went green in forward yellow in nuetral red in reverse, steering was fine but motor would'nt run.
Took it out and put my fingers on the shaft and pulled the trigger and could feel it pulse through the shaft, forward and reverse but it would'nt spin.
Ordered another motor for it (same one) so have to wait for the next fun evening
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Old 04-22-2013, 08:46 AM
  #479  
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FYI -
Don't forget if you change to a LiPo you must reset the ESC to LiPo mode =
If you don't you can fry stuff...



Originally Posted by MaxThrottle
So i was going to meet the guys to run in the parking lot last night and was charging batteries and swapping some wheels and put a battery in to check everything and everything worked but the motor, esc went green in forward yellow in nuetral red in reverse, steering was fine but motor would'nt run.
Took it out and put my fingers on the shaft and pulled the trigger and could feel it pulse through the shaft, forward and reverse but it would'nt spin.
Ordered another motor for it (same one) so have to wait for the next fun evening
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Old 04-23-2013, 04:03 AM
  #480  
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havent gone with the lipo's yet but the other guys have
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