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Smaller front sprocket


CBRXXRAGE

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Guest rockmeupto125
my 98 just has frt 1 dwn. the 97 has 1 frt dwn & timing advance & barrett  

clutch & jet kit.   the 98 gets twice as much mpg than the 97. the 97 will  

wheelie like a mother :bigshock:

I presume you mean Barnett. What plates did you use, and how would you compare the clutch to the stocker?

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12/60 here.

:lol:  

Just kidding.  Actually 16/45, but I have an 18/43 available in the garage for speed runs and a 47 waiting on my 15 front to get here so I can try to lower my ET's at the local track.

What do you turn in the quarter mile? I am also installing N2o on my bike in the spring.

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Guest rockmeupto125

Presumably, the tighter radius of the smaller sprocket will dictate greater flexion of the chain as it passes over the teeth, resulting in greater wear.

I question this in comparison to the overall scheme of things. There's no stop, or change in clearance as the chain flexes, and in actuality, you are dividing forces over time over a great area and arc of the chain link pins AND rollers.

I don't think a properly maintained chain and sprocket will wear significantly faster on a 15 tooth front sprocket than on a 17 tooth. It might in a laboratory, or an engineering thesis.......but not in the real world with its myriad of variables.

But to examine the situation.......

As that 15 tooth sprocket turns, it has 12 percent less teeth...and therefore the sprocket wear will occur 12 percent faster. Sprocket wear is the biggest contributor to chain wear...as the sprocket teeth become scalloped and the chain links ride higher and higher on the sprocket teeth, the chain pins are forced to their max tolerances, increasing the wear.

Chain wears the sprocket, the sprocket wears the chain. At a certain point in the service life, the chain has increased its clearances enough to that it no longer fits the sprocket. At that point wear of both components, which has been essentially linear, becomes exponential.

And I have an idea that if you eliminated one side of the wear "pair," you'd significantly extend chain life. The next opportunity I have, I'm going to change front sprockets at an arbitrary halfway point, and see if chainlife is extended. By eliminating the wear of the sprocket, and allowing the chain to once again ride the teeth properly, my hypothesis is that chain life will be close to doubled. The trick is to choose the point at which the chain sprocket pair changes from linear wear to exponential wear. This might be fun.

And to use a 15 tooth you would need to drop to 108 links. Stock can extend only enough to use a 16.

Superblkbrdxx..........how's the engagement point with the clutch? Is it really touchy, so as not to be such a good idea if you were to be in a parking lot, crowded slow traffic, or with a passenger/gear? Thanks!

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CBRXXRAGE, the fastest I've run in the 1/4 so far is 10.50. That was a long time ago though, all motor, and I weigh 240#'s. I have nitrous on my bike now but have never made a good pass on the juice. It either flies up on me without the bars or I bog off the line with the bars, hence the reason for the gear change. My goal is high 9's with a 15/47 sprocket combo on the bars and bottle. I figure I can turn around 10.30 or so with my current setup on motor and enough passes at the 1/4 to get consistent.

I run 6.40 in the 1/8 on motor, but that's because I run at that track all the time and am used to it. The 1/4 track is 100 miles away and I only go about once a year, so I never get used to that track and it's different conditions.

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