52LikesTeam Losi JRXS Type-R
07-08-2009, 08:01 AM
#9811
Because we run negative camber on all wheels, only the outside tyres have have a full contact patch(if the right amount of camber is used) in a corner. So in a way you want as much weight on the outside as possible so the wheels with the right geometry are doing the work. If you unload the inside too much you will diff out and lose drive.
If you run a spool you want as little weight as possible on the inside tyre so its not scrubbing against the outside. But too much roll and you could traction roll! Also more roll means a less reactive car in tight technical sections of a track. To quote Dragonfire, "its all a compromise".
07-08-2009, 09:56 AM
#9813
Tech Apprentice
07-08-2009, 10:51 AM
#9814
Its the distance between the center of gravity and the roll center. The larger the distance the more leverage = more lean. Lower roll center is going to be a greater distance from the CG. Good example would be off road cars. High CG, low RC. Motorcycles are the opposite. Low CG and very high RC, thats why they lean into a corner.
I use this software http://www.rctech.net/forum/electric...alculator.html
For me having roll centers within a mm front to rear seams to work out the best for me.
I use this software http://www.rctech.net/forum/electric...alculator.html
For me having roll centers within a mm front to rear seams to work out the best for me.
Lower roll center will transfer more weight onto the outside tyres in a corner. Higher roll center, in comparison, will keep a little more on the inside tyres.
Because we run negative camber on all wheels, only the outside tyres have have a full contact patch(if the right amount of camber is used) in a corner. So in a way you want as much weight on the outside as possible so the wheels with the right geometry are doing the work. If you unload the inside too much you will diff out and lose drive.
If you run a spool you want as little weight as possible on the inside tyre so its not scrubbing against the outside. But too much roll and you could traction roll! Also more roll means a less reactive car in tight technical sections of a track. To quote Dragonfire, "its all a compromise".
Because we run negative camber on all wheels, only the outside tyres have have a full contact patch(if the right amount of camber is used) in a corner. So in a way you want as much weight on the outside as possible so the wheels with the right geometry are doing the work. If you unload the inside too much you will diff out and lose drive.
If you run a spool you want as little weight as possible on the inside tyre so its not scrubbing against the outside. But too much roll and you could traction roll! Also more roll means a less reactive car in tight technical sections of a track. To quote Dragonfire, "its all a compromise".
. Thanks guys this is great i think I'll have to make sure to spend a quiet day at the track trying out very drastic differences between the front and the rear of the car.
07-08-2009, 02:33 PM
#9815
Its the distance between the center of gravity and the roll center. The larger the distance the more leverage = more lean. Lower roll center is going to be a greater distance from the CG. Good example would be off road cars. High CG, low RC. Motorcycles are the opposite. Low CG and very high RC, thats why they lean into a corner.
I use this software http://www.rctech.net/forum/electric...alculator.html
For me having roll centers within a mm front to rear seams to work out the best for me.
I use this software http://www.rctech.net/forum/electric...alculator.html
For me having roll centers within a mm front to rear seams to work out the best for me.
Lower rollcenter = more grip / less response
Higher rollcenter = less grip / more response
What you need to be fast depends on the grip levels and layout but because the type R is ultra responsive at all times (due to chassis layout) I feel that with rubber low will always give better results. Foam however always has grip so I would lean the other way with high roll centers.
As mentioned above rollcenters are rarely the same front to rear. This is what is called the roll axis which is an imaginary line running between the front and rear rollcenters (sorry no pics). The best use for this line is to understand how much of your chassis weight is effecting each end of the chassis. I generally run a roll axis leaning towards the front which means that more weight is over my front wheels all the time giving greater grip at that end. This however takes some experience to handle as the chassis will "lose" the rear end in line with the amount you lift off the throttle.
Anyway setup is a pretty complicated thing but as mentioned a few posts ago is usually an adaptation of the chassis to suit the driver so once you find a happy medium setup there will be minimal change from track to track.
Hope I haven't confused everyone...
07-08-2009, 03:34 PM
#9816
Can someone please help. I have searched, google searched and it is still not clear to me. I am very new to touring car.
What is the recommended gearing, spurs and pinions to run on an asphalt track typically for a 13.5 motor. I can use either a Novak or Hacker 13.5.
Also, what is better, a 48 or 64 pitch spurs and pinions? I read that 64p strip easy on asphalt, is this really a bad problem?
I believe I already ordered a 92t 48p pinion, however I am going to place another order tomorrow to make sure I get the right gearing.
I can run some boost using a Tekin RS Pro.
Please help JRXS pros!
What is the recommended gearing, spurs and pinions to run on an asphalt track typically for a 13.5 motor. I can use either a Novak or Hacker 13.5.
Also, what is better, a 48 or 64 pitch spurs and pinions? I read that 64p strip easy on asphalt, is this really a bad problem?
I believe I already ordered a 92t 48p pinion, however I am going to place another order tomorrow to make sure I get the right gearing.
I can run some boost using a Tekin RS Pro.
Please help JRXS pros!
07-08-2009, 06:18 PM
#9817
I'll simplify that for you more...
Lower rollcenter = more grip / less response
Higher rollcenter = less grip / more response
What you need to be fast depends on the grip levels and layout but because the type R is ultra responsive at all times (due to chassis layout) I feel that with rubber low will always give better results. Foam however always has grip so I would lean the other way with high roll centers.
As mentioned above rollcenters are rarely the same front to rear. This is what is called the roll axis which is an imaginary line running between the front and rear rollcenters (sorry no pics). The best use for this line is to understand how much of your chassis weight is effecting each end of the chassis. I generally run a roll axis leaning towards the front which means that more weight is over my front wheels all the time giving greater grip at that end. This however takes some experience to handle as the chassis will "lose" the rear end in line with the amount you lift off the throttle.
Anyway setup is a pretty complicated thing but as mentioned a few posts ago is usually an adaptation of the chassis to suit the driver so once you find a happy medium setup there will be minimal change from track to track.
Hope I haven't confused everyone...
Lower rollcenter = more grip / less response
Higher rollcenter = less grip / more response
What you need to be fast depends on the grip levels and layout but because the type R is ultra responsive at all times (due to chassis layout) I feel that with rubber low will always give better results. Foam however always has grip so I would lean the other way with high roll centers.
As mentioned above rollcenters are rarely the same front to rear. This is what is called the roll axis which is an imaginary line running between the front and rear rollcenters (sorry no pics). The best use for this line is to understand how much of your chassis weight is effecting each end of the chassis. I generally run a roll axis leaning towards the front which means that more weight is over my front wheels all the time giving greater grip at that end. This however takes some experience to handle as the chassis will "lose" the rear end in line with the amount you lift off the throttle.
Anyway setup is a pretty complicated thing but as mentioned a few posts ago is usually an adaptation of the chassis to suit the driver so once you find a happy medium setup there will be minimal change from track to track.
Hope I haven't confused everyone...
07-08-2009, 07:00 PM
#9818
07-08-2009, 08:47 PM
#9819
metalracer2-- their will be a couple of guys running the losi including my self down here at westcoast rc hope to see you out at the track it will be open very very shortly...
Pablo are you the one in charge of all the ordering of that lay shaft i need to order one, my buddy Chris is running one of the flyingfox shafts out here and its working good, need to see what i have to do to get my hands on one??? thanks
Pablo are you the one in charge of all the ordering of that lay shaft i need to order one, my buddy Chris is running one of the flyingfox shafts out here and its working good, need to see what i have to do to get my hands on one??? thanks
07-08-2009, 09:47 PM
#9821
can anyone help me and give me any gearing suggestions?
07-08-2009, 10:14 PM
#9822
hope this help Mattnin
Can someone please help. I have searched, google searched and it is still not clear to me. I am very new to touring car.
What is the recommended gearing, spurs and pinions to run on an asphalt track typically for a 13.5 motor. I can use either a Novak or Hacker 13.5.
>>108 T 64 P Spur with a 45 pinion should be good starting point if you have a PRS spur adaptor.
Also, what is better, a 48 or 64 pitch spurs and pinions? I read that 64p strip easy on asphalt, is this really a bad problem?
>>if your track is prepped commercial track go with a 64P, for parking lot or street run go with a 48P spur
I believe I already ordered a 92t 48p pinion, however I am going to place another order tomorrow to make sure I get the right gearing.
>>>>order 45T-50T pinions. with 108T spur in 64Pitch if you have a PRS adaptor, if not wait for few minute. I ll look up gear chart
>>I assume you ordered Losi 48P spur gear LOSA3973 if you wanted to use that gear then you will need 37T-40T in 48P gears but you will need to double chck if motor can move that far to fits those pinion.
>>bottom line is you need final Gear Ratio 4.2 to 4.5 for a 13.5 motor
I can run some boost using a Tekin RS Pro.
Please help JRXS pros!
>>>sorry me no pro~
Can someone please help. I have searched, google searched and it is still not clear to me. I am very new to touring car.
What is the recommended gearing, spurs and pinions to run on an asphalt track typically for a 13.5 motor. I can use either a Novak or Hacker 13.5.
>>108 T 64 P Spur with a 45 pinion should be good starting point if you have a PRS spur adaptor.
Also, what is better, a 48 or 64 pitch spurs and pinions? I read that 64p strip easy on asphalt, is this really a bad problem?
>>if your track is prepped commercial track go with a 64P, for parking lot or street run go with a 48P spur
I believe I already ordered a 92t 48p pinion, however I am going to place another order tomorrow to make sure I get the right gearing.
>>>>order 45T-50T pinions. with 108T spur in 64Pitch if you have a PRS adaptor, if not wait for few minute. I ll look up gear chart
>>I assume you ordered Losi 48P spur gear LOSA3973 if you wanted to use that gear then you will need 37T-40T in 48P gears but you will need to double chck if motor can move that far to fits those pinion.
>>bottom line is you need final Gear Ratio 4.2 to 4.5 for a 13.5 motor
I can run some boost using a Tekin RS Pro.
Please help JRXS pros!
>>>sorry me no pro~
Last edited by SweepRacingUSA; 07-08-2009 at 10:27 PM.
07-08-2009, 10:59 PM
#9823
Good to hear they working well. I'm not far from showing you all my next part for the Type R!!!
07-08-2009, 11:07 PM
#9824
da jon, thank you very much for all the information.
07-09-2009, 04:36 AM
#9825
I'm the person who makes them. If you are in the USA you are better off ordering from www.skyrocketbatteries.com He sells them for the same price as me and his postage is lower and faster as he is also based in the states.
Good to hear they working well. I'm not far from showing you all my next part for the Type R!!!
Good to hear they working well. I'm not far from showing you all my next part for the Type R!!!
Any clues?