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I know this issue has been beaten to death, but curiosity got the cat. We love our 900s handling and performance on the back roads, but we want lower RPMs at highway cruise. Using gearingcommander.com, I mapped out some speeds of at different RPMs for the stock 900, Vstar 950, Harley Davidson Sportster, Suzuki C50, and the 900 with three modifcations: the front pulley, both pulleys, and the front pulley plus the 200/70 tire. See the table below. The numbers are in miles per hour.


RPM Stock Vstar HD Suzuki 900 w/ 900 w/ 900 w/
900 950 Sportster C50 Front Fr & Rr Front
Pulley Pulleys + 200/70

2500 42.7 46.4 45.6 41.2 45.4 48.3 47.4
3000 51.3 55.6 54.7 49.4 54.5 58 56.9
3500 59.8 64.9 63.8 57.7 63.6 67.7 66.4
4000 68.4 72.4 72.9 65.9 72.6 77.3 75.9
4500 76.9 83.5 82 74.1 81.7 87 85.3


Here are my takeaways.

1. I've read/heard the Vstar 950 was aimed at the Vulcan 900. I can only believe that Yamaha tried to address what it perceived as the 900s deficiencies. Let's imagine that 3500 RPMs is a nice cruising level on the highway. The bigger bikes go much lower, but this is about where my 900 feels pretty good. At that RPM level, the 900 goes about 60 (the second column), while the Vstar goes about 65 (third column). For comparison, I've included the Sportster and the Boulevard. The Sportster speed at each RPM level is closer to the Vstar. The Boulevard is slower than than the 900 at a given RPM.

2. If you read the C50 forums, you'll see that they also complain about high revs at highway cruise. There is no right or wrong answer here: There is some tradeoff between low end torque and low cruise RPMs. However, I think the large number of complaints, the Vstar 950 response, and the fact that the Sportster is also geared with lower RPM/mph all tell us something. For whatever reason, Kawasaki geared the bike with higher RPMs, and Suzuki went even higher (though the C50 is significantly smaller at 800 ccs). There seem to be two views going on about how to gear these bikes.

3. Suppose you add just the front pulley to the 900. You've now got essentially the same RPM/mph ratio as the Sportster, which is just below that of the 950. (Compare the fourth and the sixth columns in the table.)

4. Suppose you add both pulleys. You've now got the lowest RPM/mph ratio of the group, by a significant amount.

5. Suppose you add the front pulley and a 200/70 rear tire. The RPM/mph ratio is a bit higher than it is with both pulleys, but it is still the lowest of this group of bikes.

6. I can't speak to the low end torque v. low RPM/mph ratio tradeoff. I suspect its partly personal preference, though at some point going too low with the cruise RPM/mph ratio mucks up the initial start in 1st gear too much. Recognizing that the Vstar is a slightly bigger bike, some might think doing two of the mods (both pulleys or the front pulley and rear tire) would tax the low end torque too much. However, several who have done these mods seem to like them.

I'm pretty sure I'm doing the front pulley, getting used to it, then deciding whether to add a bigger tire when the time comes.

Cheers,
Dan
 

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I owned a C50 and I agree, it needed a 6th gear badly BUT that bike was terribly buzzy at all revs. My hands were numb after 15min on that bike. I have never ever gotten numb on my 900. IMO the smoothness of the 900 blows away the 800cc in the suzuki. just my 2 cents.
 

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