Engine sprocket teeth and the number thereof

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biker_k
Posts: 74
Joined: Fri Jul 21, 2006 9:41 pm
Bikes: 48 chop, 60 FL, 91 FXSTS
Location: Spokane, WA
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Engine sprocket teeth and the number thereof

#1

Post by biker_k » Mon Jul 31, 2006 8:33 pm

Hi all,

I wonder if someone could explain to me the effects of changing the engine sprocket. Specifically going up in teeth number. The sprocket that I currently have is a 22 tooth sprocket with the compensator unit. I'm going to eliminate the compensator and was looking at JP's prices. The 22 tooth sprocket is 7 bucks more then the 23 or 24 tooth. If I increase my tooth count to 23, what will be the effects on the bike?

I've played this over in my head a few times and just want to see if my thinking is correct. More teeth on engine sprocket, no changes on drive sprockets = higher torque and higher top end speed?

Thanks



King
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#2

Post by King » Tue Aug 01, 2006 12:53 pm

biker_k

In general the smaller the engine sprocket the better the low speed performance. Thus, your 22 tooth is good for around town but you might feel a bit over reved at highway speeds.

The stock set-up for Pans is a 23 tooth engine sprocket, 37 tooth clutch basket sprocket and, a 22 tooth tranny sprocket, and a 51 tooth rear sprocket (mounted on the brake drum). This gives an "overall" ratio of 3.73 and was designed for driving in the fifties i.e. ~55mph cruising.

To get better highway performance I have gone as high as 25 tooth engine sprocket and 25 tooth tranny sprocket (the clutch drum and rear sprocket are not changeable). This gave an over all ratio of 3.02 which was great for the Interstate but had me changing gears a lot and the bike was a dog in town! Currently I am running a 23 tooth engine sprocket and 25 tooth tranny sprocket (for an overall ratio 3.28) which I feel is about right.

So it really a matter of preference and where you ride that should determine your sprocket sizes. But I would go with the 23 tooth non-compensated sprocket and see how you like it. Then, if you want better highway cruising performance you can up the size of your tranny sprocket.

Good Luck

King

biker_k
Posts: 74
Joined: Fri Jul 21, 2006 9:41 pm
Bikes: 48 chop, 60 FL, 91 FXSTS
Location: Spokane, WA
Contact:

#3

Post by biker_k » Tue Aug 01, 2006 3:52 pm

Thanks King.

I'm getting ready to order today and I think I will try a 23 tooth first to see how it rides. Thanks for your help.

VT

#4

Post by VT » Wed Aug 02, 2006 3:51 am

With a chain primary on my '59 stock style Pan, I liked a 24-T motor sprocket, a standard clutch drum sprocket and a 25-T trans, sprocket. This gave me a non-winding-out feeling at 63 mph.
Stett told me going to a 26-T trans. sprocket would stretch the span between 1st and 2nd, so I stuck with the 24-T motor, stock clutch drum sprocket and 25-T trans. and liked it. Now I'm going to enclosed belt and hope my 4th gear ride stays the same low-lope at 63 mph.

biker_k
Posts: 74
Joined: Fri Jul 21, 2006 9:41 pm
Bikes: 48 chop, 60 FL, 91 FXSTS
Location: Spokane, WA
Contact:

#5

Post by biker_k » Wed Aug 02, 2006 7:18 pm

VintageTwin..

Thanks for the response. I decided that I would start out with the 23T sprocket and go from there. If I'm not happy with that, I'll try some different combinations until I get to the one that suits my riding style.

I ordered the sprocket, and the nut and sprocket key combination. Is there anything else that I need?....shims?....washers?.....anything that I have forgotten or is the sprocket and nut/key enough?

Thanks you guys.

VT

#6

Post by VT » Wed Aug 02, 2006 8:30 pm

V-Twin and J&P have a locking tab washer that could go under the nut on 55-up (17-0945). Looks as though you get an new nut with it.
Just jamb a broomstick under the top of the chain at the motor and use a clutch hub locking tool (a clutch drive plate with a handle welded on it) to hold all 10 of the studs on the hub steady, while you pull the sprocket shaft nut to 80-100 ft. lbs with a torque wrench.

biker_k
Posts: 74
Joined: Fri Jul 21, 2006 9:41 pm
Bikes: 48 chop, 60 FL, 91 FXSTS
Location: Spokane, WA
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23 tooth works great!

#7

Post by biker_k » Tue Aug 29, 2006 8:28 pm

Hi you all....just thought that I would give you an update. I changed out the compensator assy with a 23 tooth sprocket and it did confirm that the compensator was either not preloaded properly or the spring was worn out, but the slippage was eliminated. Also, I really like the way the 23 tooth sprocket performs. The bike was running strong and reliably now for 2 weeks. Thanks for all your advice!!!

captainharley
Posts: 52
Joined: Sat Aug 12, 2006 7:54 pm
Bikes: '65 FL
Location: Central FLorida

#8

Post by captainharley » Wed Aug 30, 2006 8:51 am

My scooter is a '65 FL set up as a Superglide with front and rear discs.
On the motor is a solid 24 tooth, stock clutch basket, 22 tranny gear (so
my speedo is correct) and a 48 tooth rear wheel sprocket. Runs smooth
city/highway. Motor only slightly warmed over with andrews 1st gear.
AMF :wink: Ride Safe





You've never lived 'til you've had a quarter ton of hot chrome steel between your legs!

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