compensator gear change

Transmission, clutch, chains and belts
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socalrider
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compensator gear change

#1

Post by socalrider »

so thanks to bosheffs help now i got the right compensator gear,24 tooth, everything fits as it should in regards to the primary chain. what changes in performance can i expect assuming all else is per factory build. higher or lower rpm's at highway speeds? easier kick start ? the bike is a 1965 flh
gracias,
arnulfo
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Re: compensator gear change

#2

Post by Sir_Rat »

I'm gonna take a wild guess at this one and say you're probably not gonna see/feel any noticable difference on this, but your primary drive should last longer and be less prone to leaks and might even be easier to shift. Like I said I'm only guessing here......Aloha...Mike
Bosheff
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Re: compensator gear change

#3

Post by Bosheff »

Theoretically speaking, the taller the engine sprocket (Higher number numerically), the slower it will be out of the gate, and the less RPM's you'll be turnin at the same road speed you did with the 23. This sprocket will hypothetically give you a higher top end and better fuel mileage because of less engine RPM. You will probably not even notice the difference in the seat of the pants, but a tachometer and fuel mileage will tell the story. I wouldn't count on any difference when trying to kick her to life. If you don't think it's rollin over fast enough when kickin it, check clutch adjustment for slipage, and make sure yer runnin the correct mainshaft starter gear....bosheff
kitabel
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Re: compensator gear change

#4

Post by kitabel »

If you had a 23, the ratio of decreased torque is exactly the ratio of the sprockets: 23/24 = 95.8%, or 4.2% less.
The speed change is, again, exactly the ratio of the sprockets: 24/23, or 104.3%.
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Re: compensator gear change

#5

Post by Cotten »

kitabel wrote:If you had a 23, the ratio of decreased torque is exactly the ratio of the sprockets: 23/24 = 95.8%, or 4.2% less.
The speed change is, again, exactly the ratio of the sprockets: 24/23, or 104.3%.
Yes I agree,
It's pretty subjective.

....Cotten
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Re: compensator gear change

#6

Post by kitabel »

The unfortunate part of this type of swap (taller) is that the negative aspect (sluggish 1st gear off the line) is much more noticeable than the very minor change in engine speed at cruising MPH.
Example: a 74" engine feels like 71", or there's a passenger behind you.

However, using 23/22 gearing (3.73:1), the engine was turning 2,893 RPM @ 60 MPH. Going up to 24 (3.574:1) only drops it to 2,771. For many people, losing 122 RPM isn't worth it. Even at 100 MPH, the reduction is only 202 RPM.
socalrider
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Re: compensator gear change

#7

Post by socalrider »

Thank you for all the great info. To everyone. This bike will never be riden hard so. I'm not too concerned about how quick it is off the line. 60-65 mph is about the fastest I go, so for me. The lower rpms at the higher speeds is preferable, along with the fact that it will be back to factory build.
Gracias
Arnulfo
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Re: compensator gear change

#8

Post by RUBONE »

This bike will never be riden hard so. I'm not too concerned about how quick it is off the line. 60-65 mph is about the fastest I go, so for me. The lower rpms at the higher speeds is preferable, along with the fact that it will be back to factory build.
Pity!
Robbie
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