fastpakr

Shadow Shack's experience with raising gearing on a larger bike actually mirrors my own on a Suzuki GS750 several years ago. It was unnecessary and reduced the torque available at any given speed.

However, my experience on the Rebel was vastly different. There is a reason for this, and it is apparent if you look at a dyno chart of the Rebel engine. Peak output has actually been passed by the time you hit 70mph. With the stock gearing, anywhere from 70mph and upward you're actually getting reduced power from the engine. By using the 15 tooth front (or 30 tooth rear) you're just raising that peak point a few miles per hour. For those cruising around on back roads, it just isn't a big deal. Use whatever you like. If you're using it to commute on the highway, a moderate reduction in RPM can smooth out the buzz and actually give you a tiny bit more power on tap at those speeds.

This is an extremely rare case. For almost any other production motorcycle, top gear doesn't hit peak power until far beyond legal speeds. The CMX250 is one of the few I've run into where raising the gearing would actually increase the power available.

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Blueberry

I have stock gearing. We don't ride over 55 mph and at that speed the Rebel makes the most torque.

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Ride Safe, Blueberry
1985 Honda 250 Rebel
1970 Honda SL 90
2008 Royal Enfield Electra 500

JunkyardDog

To me, 1 or 2 mpg just doesn't make a difference. Both my Rebel and my XT225 get ridiculously good gas mileage compared to my car and truck. IMO, the Rebel already doesn't have enough power in 5th gear, and slows down considerably on level roads when you encounter a headwind. The AZ desert is a fairly windy place most of the year. Even with stock gearing, I have to downshift into 4th more often than I would like, both because of wind, and climbing hills. Jerry.

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fastpakr

If you're running 55mph, that's true. If you're running 70mph, your available power is LOWER in 4th than it would be in 5th, because you're already above peak hp in the power curve in 5th with stock gearing at that speed. Going to 4th just makes it worse (and puts you above redline). 15 front or 30 rear gives you a little more breathing room.

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JunkyardDog

I run a max of indicated 65 mph, which according to GPS is an actual 60.something. I never run any 4 stroke engine at wide open throttle for any length of time. An indicated 65 mph keeps the engine RPM at a safe speed. Jerry.

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fastpakr

If that makes you happy, then go for it. Many others have run their own bikes for north of 50k miles at whatever speed they needed to. I personally took mine on several multi-hour interstate trips. Was it the ideal bike for it? No, that's why I have the Vulcan 500 now. It certainly handled it just fine. No oil was burned, nothing overheated, etc. It didn't harm it a bit.

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