Trans. Sprocket

[exeric]

I am replacing the sprocket driver gear, and drive sprocket at the transmission on my '40 Chief. I have been running a 23 tooth sprocket and not very happy with it. It felt like the engine was winding out and that I was leaving a lot of potential top end on the table. My question is; would a 24 tooth sprocket be an improvement, or is the 23 the best all around sprocket. Changing out sprockets is not my idea of fun, so I'm looking for some real world insight.

[fillibuster]

I am replacing the sprocket driver gear, and drive sprocket at the transmission on my '40 Chief. I have been running a 23 tooth sprocket and not very happy with it. It felt like the engine was winding out and that I was leaving a lot of potential top end on the table. My question is; would a 24 tooth sprocket be an improvement, or is the 23 the best all around sprocket. Changing out sprockets is not my idea of fun, so I'm looking for some real world insight.

I started with a 24 in 1990, moved up to 26 (a friend had it). I loved the fast highways, hadn't ridden for about 10 years. In 91, on the way home from the Winnipeg Road Run (Buffalo Hunt Road Run, excuse me Ross), my riding partners and I detoured to Shakopee Mn, then Henderson to visit Diane Trimbo whose husband Kenny had died recently. I bought a 27 and 28 tooth from her. Had to open up the chain guard a bit for them to clear. Have run them all, and prefer the 27 tooth for solo riding. .. The 28 tooth, by my math, yields the same ratio as an overdrive transmission with 23 tooth, which I believe is "standard". .. I rode to Davenport (450 mi) in 1992 with the 27t, took me 8hr, 15 min. Sweet spot at around 70+ (balance of 63% on flywheels).

Nowadays I do the long hauls on a "duct-taper" (2003 anniversary HD), the Chief runs a side-car sprocket (23t), and I don't drag race and spank the knuckleheads anymore, although I brag about it once in a while.

I would recommend a 26tooth, even with stock 74" motor, if you want to know the difference. Good for the highways. Do a fresh clutch, though.

[indianut]

i like a 23. I tried a 24 on my '47 once and it felt like I was lugging it at normal Pinellas County speeds. On the road it was OK. That being said I ran a 23 on my 37 80" when I went to Mass. and Out West. 8500 miles and the 23 felt good at my Comfort Zone of around 60 MPH. but then I prefer 23/51 on a Panhead. I feel like it keeps the engine in the Power Band. 3300 or so RPM is fine for me! PS Eric I forgot to talk to you about the Intake Seals the other day. If you come up and bring your Manifold we can set it up.

[redfred84]

Eric,
Good to see you, altough only briefly, at Eustis. The gearing will depend on your engine, and your riding, multiplied by your terrain. If your '40 is a stock 74" with no real performance mods, then breaking it in with a 23t is fine. If you have any performance mods; carb Bonnized, or cams, etc... then 25t should be just fine, especially if you are just riding in flat Florida. Me thinks you will find a 25t to be more user friendly, perhap even a 26. If you decide to go road racing in the Rockys, you can always fit a 24t!
Merry Motoring, RF.

[Bill Huth]

Eric, I started with the 24 on a new engine break in for my '48, and went to a 25. Mine is a 74" w/bonn cams/followers. I'm running an o-ring chain which looks like it would have some clearance issues with the chain guard if I went bigger, since the o-ring chain also adds a little width. It feels like it would have some more oompf on the highway if I went larger, but it will do 85 as is. Runs smooth in the 60-65 range. Bill

[elt]

Eric
a 23 tooth sproket is the best in third gear but shifting into 4th and over is the only way to ride in the 21st century.It sure fixed my 48 Cheif.No one will know unless they count your shifts as the case looks the same as stock.it is money well spent if you are actually going to ride with the trafic.
Elton
AMCA 5738

[exeric]

Eric
a 23 tooth sproket is the best in third gear but shifting into 4th and over is the only way to ride in the 21st century.It sure fixed my 48 Cheif.No one will know unless they count your shifts as the case looks the same as stock.it is money well spent if you are actually going to ride with the trafic.
Elton
AMCA 5738

Elton, I'm sure you're right because you can feel the un-tapped potential of an Indian motor, and I can only imagine what that extra gear would deliver. However, I also know what it would do to my bank account.

[redfred84]

The way I look at it Eric, is like this; Just think of how much you will save by relieving your engine of all that un-due stress, and rpm from utilizing the OD! Your engine should lase twice as long because of the lumbering, low rpms it will enjoy from the 4spd trans. At least that's how I justified buying 5 of them for my own fleet! I haven't been sorry. They more than double the enjoyment of the machine.
You deserve it; go for it!
RF.

[redfred84]

The way I look at it Eric, is like this; Just think of how much you will save by relieving your engine of all that un-due stress, and rpm from utilizing the OD! Your engine should lase twice as long because of the lumbering, low rpms it will enjoy from the 4spd trans. At least that's how I justified buying 5 of them for my own fleet! I haven't been sorry. They more than double the enjoyment of the machine.
You deserve it; go for it!
RF.

[exeric]

I trust first hand experience so you and Elton have given me a lot to think about.