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runlowtim
December 30th, 2009, 9:57 PM
Do they sell any sizes of gears on the belt drive to change the gear ratio or are they the only ones they sell .The ones that come on the car. How do you figure out what gear you do have on it .Are they a formula to find ont what it is?
mikejhs82
December 30th, 2009, 10:53 PM
In the links section here on DODC. Go to BMS' website it has a technical section. In that section is a gear chart. It has, at the top of the chart the reduction of the tranny in the BMS car, and of course the gear chart. I think this may answer your question.

Mike Warner
rc_truck_racer
December 31st, 2009, 3:27 AM
Do they sell any sizes of gears on the belt drive to change the gear ratio or are they the only ones they sell .The ones that come on the car. How do you figure out what gear you do have on it .Are they a formula to find ont what it is?


In the BMS cars, the belt drive tranny provides a constant 2.52 to 1 "gear reduction" similar to the gear reduction provided by the gear drive trannies in other cars. This remains constant.

The spur is located on a shaft similar to the top shaft in normal trannies and is not part of the tranny. This can be changed.

You can also change the clutch bell.

These two adjustments allow for gear changes appropriate for big or small tracks.

Let me know if you need pictures.
rc_truck_racer
December 31st, 2009, 4:22 AM
Here's a photo... The spur attaches to the aluminum part with all the holes in it... The arched part is the break lever.

Very smooth and free flowing tranny.

Great for limited racing (2 of top 3 Limited Late Models at the 2009 USOWC were BMS cars).


http://www.bmsrcracing.com/webpagepics/rev3.jpg
mikeschellracing
December 31st, 2009, 7:26 PM
spur gear divided by clutch bell gear[example 60 spur and a 20 clutch would = 3]. multiple that number by by your transmissions reduction [bms is a 2.52] and that will give you the number of times your engine needs to turn over to get the rear tires to turn once. the example listed here would be 7.56 engine revolution = 1 rear tire revolution. at the 2008 usowc at cs, we ran 22-23 clutch and a 60 spur. 22=6.87 / 23=6.57. hope this helps. :thumbsup: