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Harley Gearing

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I have no experience with big twins, but I did lower the gearing by 4% on my 883R by going down 1 tooth with an aftermarket front pulley. That small 4% change made a big difference in ride-ability, especially in 1st & 5th gears. My general observation is that most all bikes benefit from lowering the overall gearing by 4% to 8% when mounting a sidecar.

I understand the better way to change gearing on a big twin is to change sprockets on the primary drive -- rather than switching belt pulleys. Take a look here: http://bakerdrivetrain.com/compensating-sprockets where this "sales" example is set forth: ...stock 1999 carbureted Road King. By going from a stock 25 to a BAKER 23 tooth compensating sprocket, the torque at the rear wheel will increase by 9%.... If you have access to a 1/2” impact air gun, a compensating sprocket change is a 1 hour job....

Lee Summer Grove, LA R1100GS/CSM Sidecar, Burgman/Texas Ranger, Zuma 50F, MB5, TW200, CRF250L

I have a 1999 Harley Roadking Twin cam with a champion sidecar. I changed the crankshaft sprocket from a 25 tooth to a 24 tooth which was the smallest sprocket Harley had. It is the easiest and cheapest way to go and works fine for me and I carry up to a 300 pound load in the sidecar but I would get the 23 tooth sprocket if I was to travel in the mountians.

Sidehack05 1999 H-D FLHR with Champion Legend Sidecar

sidehack05 - 7/8/2013 11:11 PM

I have a 1999 Harley Roadking Twin cam with a champion sidecar. I changed the crankshaft sprocket from a 25 tooth to a 24 tooth which was the smallest sprocket Harley had. It is the easiest and cheapest way to go and works fine for me and I carry up to a 300 pound load in the sidecar but I would get the 23 tooth sprocket if I was to travel in the mountians.

Yes, much less expansive that way and it doesn't take as long, I did a chain conversion on my final a while back for a diff. reason , I got the kit from Zippers ,that's why I mentioned the chain part. 🙂

Thanks to everyone for responding. I have looked at both Zippers and the Baker site. It does look like the primary sprocket may be the easier way. But I have to ask, why the conversion to the secondary chain if it wasn't to change ratios?

What I would do is S&S 509 cams with a less restricted air filter and some S&S quite slip ons. The 509 is a good torque cam for a 88 and is not a lot more lift then the stock cam as well as a bolt in cam now head work needed.

I put a Baker DD 6 in mine before putting the hack on and went back to stock motor sprocket. First 3 gears are low which I like pulls well on grass and hills when loaded up taking off. 6th is the same ratio as a 5 speed with the stock motor sprocket.

My plains when money is available is to build a torque monster motor that will pull well in high gear. Being mine has over 93,000 on it I want to freshen it up any how. But I have more going for me then many others as I can do all my own work including machine work.

Markh00 - 7/9/2013 7:14 PM

Thanks to everyone for responding. I have looked at both Zippers and the Baker site. It does look like the primary sprocket may be the easier way. But I have to ask, why the conversion to the secondary chain if it wasn't to change ratios?

For track days ,the belt doesn't like track days when you're putting 94 hp on the ground + a 30 hp nozzle 🙂

When Harley went to a 6 speed they went higher on the wheel pulley which made the over all gearing higher but in six gear it is still 1 to 1 like a five speed. Backer does the same but by putting a larger motor sprocket gear instead of the wheel pulley which is really a better way to do it.

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