if i only change the 25 tooth motor gear to the 24 tooth will i have to change the chain?

 

would like to know the same question, I plan to swap out the sprockets between now and spring ,see how the tensioner pulls the chain in place

 

I was going to install the SE 1.7:1 gear change and if memory serves me there is a 24 tooth sprocket that comes in that kit... and yes they say the chain is shorter in the SE Catolouge... I would check it out very closely if I where to do this...
Check out the baker drive train web site for the gear calculator , it will give you mega information on the rpms' you will be turning.
Rob

 

I went from a 25 tooth compensator sprocket to a 24 tooth on my '00 FLHT and they did not need to change the chain.

I paid to have it done at a HD Dealership (sprocket, gasket, oil, & labor about $150) and am pleased with the results. I was told that contrary to logic, it would notchange the mileage and that is what I have observed.

5th gear RPM's at 70 mph went from about 2,850 to about 3050.

I could really feel the difference in passing power and it did not screw up the speedometer.

This is one mod that I would do again as you get a good increase in passing power at low cost --- without screwing up engine reliablility.

 

The SE kit mentioned earlier is a 21 tooth sprocket that comes with a shorter chain. Compared to a stock 3.15:1 final drive, the SE kit yields 3.75:1 and adds about 800 rpm at 70-80 mph.

Going from 25 to 24 tooth sprockets doesn't require a shorter chain according to several posts I have read previously. It yields about 3.25:1 final drive. EFI touring models had 3.37:1 for several years, ending in '01 IIRC: the 24 tooth compensating sprocket and 37 tooth clutch sprocket.

I will probably do the 24 tooth only or both it and the 37 tooth sprocket this winter. Either will make the bike quicker to accelerate and add only about 200 rpm at 70-80 mph.

 

I would rather go the other direction, how about a 26, 27, or 28 tooth compensating sprocket. I rarely jack rabbit start and would like lower RPM at cruise.

BUT, I have not found such a beasty.
Any ideas?
...gene

 

No, been there done that.

 

Thanks for the correction Harelypingman, I didnt ahve the info in fron of me to correctly identify teh tooth count.
With that being said though, the baker web site has a gear calculator that you can add variables to figure out the increase/decrease in RMP's
Not really ment as a plug for Baker, but the info there is interesting/infomative.
Thanks Again .
Rob

 

you may need to change your transmissionsprocket for that

 

You will have to change the chain. However Diamond who used to make that chain doesn't make that count any more. Out of the hundreds we have installed only a few didn't require any chain mod's. The adjuster was however maxed out. You can turn the chain adjuster over. It makes adjusting the chain more complicated. I would recommend a M-6. Shim it up and forget it.