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Old 09-15-2019, 07:12 AM
onionfmr onionfmr is offline
Join Date: Sep 2018
Location: Upstate NY
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Good Morning sid - I posted a picture of the Comet chart that I used to select the garter springs detailing engagement RPMs. I'm using the 146g weights. I circled the appropriate figures. This mini bike does not perform as expected with any modification. None of the gear ratio speed calculation estimators give me anything close to what I get with actual performance based on RPMs (3 different tachs, same RPMs) and actual speed via GPS. Speed on GPS app has been verified by motorcycle and car testing.

In actual testing, the mini bike starts to move at approximately 3100 RPMs with the fluorescent yellow garter springs and 3300 RPMs with the blue/silver garter springs. The white garter springs would start the mini bike moving at around 3000 RPMs. When the TAV was stock, the mini bike would start to move at approximately 2200 RPMs.

There is no hard launch to start moving the mini bike. The blue/silver garter springs gave too much delay to start, windup. The others that I've tested seem to be acceptable. I've posted pictures of the TAV and as you can see the belt isn't getting destroyed.

From my property, I have access to groomed riding trails with many turns. I road the trails yesterday at slow speed without issue. I can easily ride around at 10 to 20 MPH and then accelerate as desired.

I have some kind of mismatched Chinese 30 series TAV that was provided to me by the Tillotson engine supplier. Once I sort this mini bike out, I will be switching to a genuine Comet setup.

I actually believe that I'm getting this mini bike to perform close to what I was looking for. Based on my testing, the engine seems to be happy up to 6500 RPMs. I'm going to test the 9 tooth jackshaft sprocket and see if that gets me some more engine RPMs. Currently topping out at approximately 6000 RPMs with fluorescent yellow garter springs.

I'm at a loss with this mini bike as to how it performs based on modifications to it!
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itsid (09-15-2019)