Shaft or Belt?
#1
Tech Regular
Thread Starter
Shaft or Belt?
If you had no intension of racing anything above a 10.5 and you mainly run a 27t or 13.5ss, which drive train would be best. A friend resently told me that he knows that the big names in Japan wil only run shaft if the motor is 12t or higher?
My reason for asking is that its that time of year again for me to get my next car for the outdoor season and I'm only doing at most 10.5 b/l. I'm not worried about age of car design because most cars can be set-up to work if you know how.
My reason for asking is that its that time of year again for me to get my next car for the outdoor season and I'm only doing at most 10.5 b/l. I'm not worried about age of car design because most cars can be set-up to work if you know how.
#2
All i've ever heard is "shaft is fast, belt is better".
Make of it what you will....
Make of it what you will....
#3
I race shaft, unfortunately many manifacturers are using belts on their newer car. Shaft has the advantage that it has no wear like belts, it is faster out of the corners but a disadvantage is that the topspeed is lower than a belt. Both are very competitive on the track.
#4
Shaft drive behaves differently in left and right turns
#5
Tech Regular
Thread Starter
Bump
#6
maybe this will help answer your question. it is the answer that Bob Stellflue, designer of the Associated TC5, gave in an interview with RC Car Action.
"RCCA: What is the major advantage of a belt drive sytem over a shaft drive system in touring cars?
Bob: When RC touring car racing was just starting to come about, battery technology was in its infancy. This meant the drivetrains of the cars had to be as efficient as possible in order to maintain good motor power throughout a five minute racing format,hence the TC3's domination with shaft drive. The increase in drivetrain efficiency was worth more than the inefficiencies in chassis performance that it induced.
There are several disadvantages of a shaft drive system, and, contrary to popular belief, torque steer effects the car least of all of them. One of the biggest disadvatages of a shaft drive system is the fact the drivetrain is direct, with no damping. This means that whatever happens at the motor happens at the tires, sort of like a light switch, making the car harder to drive. When driving a shaft drive car, you have to be extremely careful when applying throttle so that the tires don't break traction. Also, when braking (especially drag brake) the tires will easily lock up. Today's batteries are far more powerful than they were even 2 years ago, powerful enough that they can overcome the inefficiencies of a belt drive system, and with that being the case, the chassis performance of a belt car over a shaft car starts to make a bigger difference. The belt systems are damped. When the driver applies the throttle, the belt will stretch a little bit and actually put up a fight before it moves. The power is then transfered smoothly to the tires making the car much easier to drive out of the corners. Likewise, once the belts are spinning, they don't want to stop abruptly, again, especially in drag brake conditions. With a belt drive system the car will roll through off-throttle sections of corners faster. For most of us, heroes excluded, this means a belt drive car will be much easier to drive at a faster average lap time."
"RCCA: What is the major advantage of a belt drive sytem over a shaft drive system in touring cars?
Bob: When RC touring car racing was just starting to come about, battery technology was in its infancy. This meant the drivetrains of the cars had to be as efficient as possible in order to maintain good motor power throughout a five minute racing format,hence the TC3's domination with shaft drive. The increase in drivetrain efficiency was worth more than the inefficiencies in chassis performance that it induced.
There are several disadvantages of a shaft drive system, and, contrary to popular belief, torque steer effects the car least of all of them. One of the biggest disadvatages of a shaft drive system is the fact the drivetrain is direct, with no damping. This means that whatever happens at the motor happens at the tires, sort of like a light switch, making the car harder to drive. When driving a shaft drive car, you have to be extremely careful when applying throttle so that the tires don't break traction. Also, when braking (especially drag brake) the tires will easily lock up. Today's batteries are far more powerful than they were even 2 years ago, powerful enough that they can overcome the inefficiencies of a belt drive system, and with that being the case, the chassis performance of a belt car over a shaft car starts to make a bigger difference. The belt systems are damped. When the driver applies the throttle, the belt will stretch a little bit and actually put up a fight before it moves. The power is then transfered smoothly to the tires making the car much easier to drive out of the corners. Likewise, once the belts are spinning, they don't want to stop abruptly, again, especially in drag brake conditions. With a belt drive system the car will roll through off-throttle sections of corners faster. For most of us, heroes excluded, this means a belt drive car will be much easier to drive at a faster average lap time."
Last edited by RocketRacer; 03-29-2008 at 10:50 AM. Reason: spelling
#7
belt
#8
I would only say shaft because there is less chance of getting dirt in the drivetrain??
#9
With the FDR's we are pulling in these cars with brushless, belt drive seems to be easier to get it lower. I recently switched from an almost TB-02R to a TA-05R and it is much smoother and easier to run consistantly
#10
Tech Apprentice
I would say belt as for the same reasons above... The big names last year in you country running 27t or13.5ss where they running shaft or belt. I'm sure if these guys thought one had an advantage over the other they would be running that drive system?
#12
Tech Champion
iTrader: (4)
Bob Stellflue is a smart guy but his explanation about belts being inefficient doesn't pan out. In the heyday of the TC3, belt cars won just as many or more racers than the TC3 did with the same "old" batteries.
In testing we at Schumacher found that due to harmonic occilation shafts were less efficient at high speed than belts and the shaft advantage on power exiting corners was so marginal it could not be seen on the track.
At the 2004 Worlds Hara told me that prior to the Worlds he tested his proven HPI Pro4 vs the new HB Cyclone back to back with the same equipment and the Cyclone was 8mph faster on a long straight than the Pro 4 was with identical final drive ratios. He also finished EVERY test run with more battery left in the Cyclone.
Shafts were just a gimmick that was marketed very well and that gimmick sold a lot of TC3's and TC3 copies.
In testing we at Schumacher found that due to harmonic occilation shafts were less efficient at high speed than belts and the shaft advantage on power exiting corners was so marginal it could not be seen on the track.
At the 2004 Worlds Hara told me that prior to the Worlds he tested his proven HPI Pro4 vs the new HB Cyclone back to back with the same equipment and the Cyclone was 8mph faster on a long straight than the Pro 4 was with identical final drive ratios. He also finished EVERY test run with more battery left in the Cyclone.
Shafts were just a gimmick that was marketed very well and that gimmick sold a lot of TC3's and TC3 copies.
#13
Tech Elite
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Join Date: Mar 2007
Location: Bristol, England, United Kingdom
Posts: 4,857
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i actually think a well configured belt is more efficient than a shaft. less bearings in a belt drive, so less binding. just as long as the belts aren't too tight.
#14
Tech Elite
iTrader: (8)
Bob Stellflue is a smart guy but his explanation about belts being inefficient doesn't pan out. In the heyday of the TC3, belt cars won just as many or more racers than the TC3 did with the same "old" batteries.
In testing we at Schumacher found that due to harmonic occilation shafts were less efficient at high speed than belts and the shaft advantage on power exiting corners was so marginal it could not be seen on the track.
At the 2004 Worlds Hara told me that prior to the Worlds he tested his proven HPI Pro4 vs the new HB Cyclone back to back with the same equipment and the Cyclone was 8mph faster on a long straight than the Pro 4 was with identical final drive ratios. He also finished EVERY test run with more battery left in the Cyclone.
Shafts were just a gimmick that was marketed very well and that gimmick sold a lot of TC3's and TC3 copies.
In testing we at Schumacher found that due to harmonic occilation shafts were less efficient at high speed than belts and the shaft advantage on power exiting corners was so marginal it could not be seen on the track.
At the 2004 Worlds Hara told me that prior to the Worlds he tested his proven HPI Pro4 vs the new HB Cyclone back to back with the same equipment and the Cyclone was 8mph faster on a long straight than the Pro 4 was with identical final drive ratios. He also finished EVERY test run with more battery left in the Cyclone.
Shafts were just a gimmick that was marketed very well and that gimmick sold a lot of TC3's and TC3 copies.
Our car has placed in many foam A's as well...I see no problem with the shaft car at all...
#15
I am pretty far from a serious racer, and am not even a current racer, I am just now working on getting back into the hobby. I have been around a LONG time, when 1200 batts where the best thing going.
I seem to remember this same type of discussion going on when belt cars where the hot thing to have and the first shaft cars started to show up. (not counting the original tamiya TC)
I personally think that yes one might be better then the other but not by any measurable difference. Drive the car well and you will be able to win with even an older car. It would be fun to see someone with top skills to run an old RS4, or something of the same vintage, VS something from today. I would bet the times would be very close.
I think that there is marketing today just like before.
I seem to remember this same type of discussion going on when belt cars where the hot thing to have and the first shaft cars started to show up. (not counting the original tamiya TC)
I personally think that yes one might be better then the other but not by any measurable difference. Drive the car well and you will be able to win with even an older car. It would be fun to see someone with top skills to run an old RS4, or something of the same vintage, VS something from today. I would bet the times would be very close.
I think that there is marketing today just like before.