R/C Tech Forums

Go Back   R/C Tech Forums > General Forums > Electric On-Road

Thread Tools Search this Thread
Old 03-16-2009, 05:55 PM   #1
Tech Apprentice
bydand53's Avatar
Join Date: Feb 2007
Location: Central Coast, NSW, Australia
Posts: 79
Trader Rating: 2 (100%+)
Default HB Cyclone TC - Final Drive Ratio

I'm new to electric having recently switched from nitro.

I've just built up a Cyclone TC and have downloaded a number of setup sheets from the company website.

Can somebody please explain why the spur/pinion ratio is multiplied by 2.4375 to obtain the Final Drive Ratio ?

Is this value a constant for this particular car or is it calculated from other factors ?
bydand53 is offline   Reply With Quote
Old 03-16-2009, 06:01 PM   #2
Tech Elite
a_main_attendee's Avatar
Join Date: Jan 2008
Location: Colorado, USA, The land of the free and the home of the brave!
Posts: 2,880
Trader Rating: 2 (100%+)

The final drive ratio determines how many revolutions the axle makes per motor revolution, the internal drive ratio is how many revolution essentially the spur makes per axle revolution. Without a motor connected, the cyclone's spur will turn 2.4375 times per the axle turns once. The internal drive is calculated by taking the diff pulley tooth count devided by the drive pulley tooth count. The spur/pinion ratio is the ratio to which the motor turns per one revolution of the spur, which is then multiplied by the internal to find the FDR.

Hope this helps.
Support your local tracks!--|--e-teamhobbyplex.com--|--corrc.org--|

NNFaN Paints - Add some pride to YOUR ride.
a_main_attendee is offline   Reply With Quote
Old 03-16-2009, 06:05 PM   #3
Tech Master
Scott B's Avatar
Join Date: Dec 2002
Location: NOR-CAL
Posts: 1,247
Trader Rating: 43 (100%+)

Actually the Cyclone TC is 2.1667 since it comes with the 18t center pulleys not the 16t that all the other Cyclone's come with.
Mugen Racing USA, Sweep Racing Tires, R1 Wurks, Protoform, Speedworld Raceway...

"On-road is racing.. off-road is 50% competitive jumping and 50% crash avoidance"...
Scott B is offline   Reply With Quote
Old 03-16-2009, 07:53 PM   #4
Tech Elite
Join Date: Nov 2002
Location: CORONA , CALIF.
Posts: 4,054
Trader Rating: 1 (100%+)

Mark Barden .
mb racer is offline   Reply With Quote
Old 03-17-2009, 08:14 PM   #5
Tech Apprentice
bydand53's Avatar
Join Date: Feb 2007
Location: Central Coast, NSW, Australia
Posts: 79
Trader Rating: 2 (100%+)
Default Problem solved

1) Now I know how to calculate the FDR, IDR and SPR and what the relationship is between them.

2) My TC came with the 39 tooth diff pulley and the 18 tooth drive pulley. Hence my IDR is 2.1667 and not the 2.4375 shown in the setup sheets.

3) I have now printed off a complete gear table for my car.

Many thanks from an extremely grateful Aussie "newbie".

bydand53 is offline   Reply With Quote

Similar Threads
Thread Thread Starter Forum Replies Last Post
Hot Bodies Cyclone Frank McKinney Electric On-Road 19762 07-26-2017 11:42 PM
R/C Stuff Selling Kenneth Tan Singapore R/C Racers 45728 09-09-2009 08:19 AM
Design my own 1:10 scale, but could I race? HellTriX Electric On-Road 42 06-23-2009 01:55 PM

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off

All times are GMT -7. It is currently 08:51 AM.

Powered By: vBulletin v3.9.2.1
Privacy Policy | Terms of Use | Advertise Content © 2001-2011 RCTech.net