Driven face spring

Figure out maintenance issues and discuss modifications
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Mikey
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Driven face spring

Post by Mikey » Mon Jul 27, 2015 6:28 pm

Has anyone replaced the driven face spring with an aftermarket and was there any noticable results?

Thought I would ask.

waspmike
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Re: Driven face spring

Post by waspmike » Mon Jul 27, 2015 7:46 pm

A lot depends on what you wish to achieve.

Whilst one can buy different counter springs they are often sold in combination with different weights and or front pulley. This is partly to 'disguise' the value of the weight used. Otherwise people would simply but different weights as quote by that manufacturer.

It is all a balancing act. The springs has to be balanced by the weights.

Generally:
If your weights are giving you good acceleration, and a good top end, but when you approach a small hill the scooter slows drastically, this may be caused by having too light of a contra spring. The contra spring helps push the rear pulley back together when torque is applied to the rear pully.

Also if you are running good at say 50MPH, and you slow down to say 35MPH. If you try to accelerate, and you have hardly any acceleration, this can also be caused by having too light of a contra spring. When you slow down, the spring is supposed to push the rear pulley together into a lower gear ratio. If the spring isn't strong enough, the pulley will remain in a high gear, and then when you try to accelerate, there isn't enough power to push you because you are in too high of a gear.

On the other hand, if your spring is too strong, then the weights may not be heavy enough to force the belt out all the way and into it's highest gear ratio.

If you go with a heavier contra spring, you may need to go to a slightly higher roller weight. Likewise, if you go to a lower spring, you may need to go to a lighter weight.

There is a very fine balance that you must achieve between the contra spring and your weights. This is only accomplished through trial and error.
Most people start playing with weights first or buy a performance variator like J Costa or Autisa.

If is economy you have in mind, then a slightly heaver weight will put you in a higher gear quicker at the expense of acceleration.
Last edited by waspmike on Mon Jul 27, 2015 7:57 pm, edited 2 times in total.

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Mikey
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Location: Las Vegas

Re: Driven face spring

Post by Mikey » Mon Jul 27, 2015 7:56 pm

Ok Thanks. I seem to be doing pretty good with my akropovic exhaust and Dr. Pulley 10 gram sliders.

waspmike
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Re: Driven face spring

Post by waspmike » Mon Jul 27, 2015 7:59 pm

I was going to say lighter weights at 10-15% which you have already done :)

I was browsing with my morning coffee hence the "lightening" response :lol:

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