Gear Pitch

[trailranger]

I was planning on using 48P as my gearing but I was told that 64P would be better.

The reason for thinking that 64P would be better is that more teeth are striking the face of the other gear at anyone time reducing the individual stress each tooth encounters. This stress is greatly affected by the gear sizes too. Too small of a pinion and only one or two teeth at a time can make contact. But this is a speed event so and the use of small pinions have been outlawed:eek:

I also thought about all the gear selections for 64P. The largest off the shelf 48P spur I can but is 38, but with 64P the limit is the 60's from PRS.

How does 98 Spur and 50 pinion sound?

[ajlovering12345]

Small pinions outlawed? Where did you see this? We dont have any rules such as this.

We use Mod gears in Europe. Mod 1.0 gears have a Pitch Circle Dia the same as the No of teath so easy to calculate. A 48T gear has a 48mm PCD so if you have 2 x 48T gears then the centres need to be 48mm apart.

We do use Mod 0.8 gears as well and they are just No of teeth x 0.8 so a 48T gear is 38.4mm PDC.

You can get any size gear you want to from a gear supplier. I get all mine from HPC gears.

[trailranger]

so AJ, i was joking bout the small pinions.

If you want to go fast, you have to gear up.

I am glad you pointed out the MOD pitch. The whole ASE "Standard" makes it very difficult. In college everything was done in metric.

[wqqdster]

American pitch works the same way for 32, 48 and 64 pitch. Divide the number of teeth by the pitch and you have the pitch diameter.

48 teeth divided by 32 pitch = 1.5 inch pitch diameter

48 teeth divided by 48 pitch = 1 inch pitch diameter

48 teeth divided by 64 pitch = .75 inch pitch diameter

I prefer 32 pitch gears beacause they are larger and less vulnerable to small variations in gear mesh. With all the power we put to these gears things do move around. 64 pitch gears are slightly smoother and probably have less parasitic drag but the teeth are much smaller and, I believe, weaker.