I overheard someone mention that droping a tooth on the front sprocket is hard on your bike. Is there any truth to this ?



Big Jeff

The motor will now turn more RPM's at the same MPH, so in theory, yes. In the real world, no.

No harder on your bike than riding 10mph faster is, and we all do that................... :roll:

Blackhawk is right, it's a little more rpm, a little less radius the chain has to turn around, but very minimal. If you slapped a 14 tooth on there, then there's a substantial increase in RPM and wear on the chain, but 16 won't change much, except for your grin factor.

:shock:

Does that mean I can do more wheelies sir?

I dunno Obby, mine won't do wheelies. I think I got a bad one :lol:

Boy Joe, a little bored there or new abacus to play with? :razz:

Now imagine, there are a couple of bikes out there with 13 factory teeth, you might as well R@R the front sprocket every 2k miles.

Has anyone gone 1 tooth over?

What is it like? Does the speedo read accurate?

I don`t want to sound like a smartass but calculation made by rockmeupto125 is ahhh,well there is an error or two.
Lets say XX makes 85 pounds of torque at peak,with 1.57 primary ratio and 1st gear ratio of 2.77 total torque of 85x1.57x2.77= 369.7 is applied to a counter shaft in the first gear.
In the 6th it would be 85x1.57x1.04=138.8 foot pounds of torque to the small sprocket.
You can`t really talk about torque in relation to the tooth,force-yes.
To calculate force apllied to the tooth you need to divide torque by number of teeth in the contact with chain and divide again by the radius of the sprocket ( from the center to where chein meets tooth).
I don`t have the radius of the sprocket in the top of my head and my girlfriend cleaned my desk,so there is no parts laying aroud,lets say it is 1/8 of the feet.
Here is how much force is on the tooth in the first gear-
370:8:1/8th=370 pounds.
What about the chain? 370 times number of teeth in contact-8,370x8=2960 pounds pounds of force on the chain.
As you can tale I`m a geek :lol:

DAMN...I started my calculations last WEDNESDAY.......and I just finished...... it all checks out. He is right :razz:

Geez, knock it off with the math already!

What do you guys do for a living, figure out decaying orbits for satelites so they don't crash on us?

I'm happy I can figure out gearing ratios if I change my gearing. :roll:

Someone once told me to Never do math in public and I don't.
But, we still love you Joe.

Wouldn't the smaller countershaft spockets increase radial loading on the countershaft bearing? Anyone care to calculate increase?

Hmmmmm.... math aside my 520 counter shaft sprocket -1 (on the 929) was waaay worked---but I think in this case it had more to do with the thickness---at 8K track miles it was waaaay "hooked"_ I am very happy I inspected it prior to re-install

All right, tomek, you did the calculations. :shock:

What can you conclude, besides you need a girlfriend, or at least Pay-per-view? :lol:

Was Joe "in the ballpark" with his estimate of increased load on the sprocket/chain?

When you replace the chain with a 16 tooth sprocket, do you need to get a 108 link chain rather than the 110 link chain that is stock??

If tooth loading concerns you, you can always keep the stock size front spocket, and add 2 or 3 teeth to the rear. (You'll probably also need a slightly longer chain)