I have a question for people who have changed their transmission sprockets for larger ones to reduce RPM's at higher speeds. I want to replace my tanny sprocket for a larger one to reduce the high RPM's in 4th gear going 60-70. At those speeds with the stock sprocket the bike sounds like it really needs that 5th gear.

By larger I assume you are talking about more teeth correct? I have searched around and on J&P Cycles I can get a 24 tooth sprocket for our sportsters. I'm extremely tired right now and my brain just isn't working like it should but obviously the more teeth the larger the sprocket would have to be to compensate them. It should also mean less RPM's.

The only concern I have is even though there are more teeth that shouldn't mean that the stock 530x106 chain won't fit right? I might have to add another link back in the chain but other than that the chain should still work correct?

 

Running a 24T presents a couple of problems.
First, the thing just barely fits. I have run one off and on over the years, but I always go back to the 23T.
You can get it to fit, but this will require you to grind some aluminum off the main shaft sprocket cover where it surrounds the bolt at the bottom. The chain will hit otherwise. Then you need to add a link to the chain as you say.

The main problem is this: A 24T is just too much gear for most Sportsters to pull. Install it and the first thing you will find is that you have to slip the clutch to get going. The bike will have no zip around town because it is geared too high. Out on the highway, after you have it running 60 mph or more you will like the 24T, but that is the only place you will like it. The trade off is just not worth it to me.
The only way I might put a 24T on is if I am headed out for a thousand mile ride on Interstate highways.
Keep with a 23T as your max. It will rev up a little, but you will have the needed torque down low around town, and I bet most of your riding is done there. Mine is......pg

 

Most of my riding is around town, but it's a "bypass." I say that because it's burden with too much traffic and an average of about 4 to 5 lights per mile. So it's a lot of stop and go, but seeing how it's supposed to be a "bypass" the speed limit is 55. As you know on the stock 21T the low end torque is spectacular, but when you get up to about 65 and the motor is just begging (and I do mean begging!) for a 5th gear. In my opinion it just sounds awful.

This is a really tough decision on what to buy. Too many teeth and you have no power at all. Too few of teeth and you don't really do too much at all, there really needs to be a 22 1/2 for that right in the middle sweet spot! I suppose since the sprockets are only around $16 a piece I will just pick up a 22 and a 23 and try them both out to see where I want it.

Thanks for the tips piniongear.

 

Good decision. My money is sitting on you liking the 23T over the 22T, but you need to try both as the cost is small, Let us know what suits your riding best. I can tell you that a 24T is certainly not what you want.
The 23T will give you good low end and ride comfortably at 55 to 60 mph. At 65 mph it will make you want that 5th gear, but everything is a trade off.........pg.

 

Don't know what your rear sprocket is, but I replaced my 21 front with a 23 and the bike was borderline geared-too-high with the 48 rear and tall rear tire I was running. A switch to a 49 tooth rear sprocket and 90 profile rear tire is what's working for me now. BTW, the 23 required a little grinding on the sprocket cover bosses for clearance, and I'm running a 108 link chain. Rpm at 70 mph is about 3400 with this setup.

 

The old brake drum Sportsters have a 52T rear sprocket. If you had a rear 48T matched up to a 23T on the front I think you were overgeared, and in fact that is what you say.
Your change to a 49T rear is still on the high side for gearing, but it sounds like it suits you. He will have a 23T and a 52T (cannot change rear sprockets on a brake drum Sporty) and will most likely be happy with that.
Again, on a newer Sportster you may need to remove some aluminum to fit a 23T but the old Sportys will take a 23T without any grinding. A 24T will need some grinding done though.
In the end he will have to decide what suits him best, and the only way to find out is hang the sprocket on there and take it for a run..........pg

 

Hey PG, you mentioned that the older bikes had a 52T sprocket on the rear drum. Mine has a 51T and a search on J&P and V-Twin only yield resultsfor a 51T. Any idea where I might find a 52T ? I have the 23T on the trans and would like that extra little bit of reduced RPM.

Rich

 

I think it was a typo. Mine is a 51T as well. And I saw another thread on here from PG that said 51 as well. I think 51 is all we can get for our years.

 

Dang it! I was hoping it wasn't a typo and that it was one more thing in his book of knowledge that I didn't know. Oh well.

Rich

 

My error Rich. I meant to say a 51T. I told you guys I am getting old.
The 51T has been on the Sportster since 1957 to as long as they still had the rear brake drum. Disc brake models allow you a choice of sprockets. Sorry for the mistake........pg