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Discussion Starter · #1 ·
Looking to lower the gearing on my 2015 Chief Classic, as in lower road speed per engine rpm. This is for sidecar duty, where first gear is too tall. Anyone know a source for smaller front pulleys (preferred) or larger rear pulleys
 

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You're looking for a larger rear pulley or a smaller front pulley. It might be easier to convert over to a chain drive where you have a wider variety of sprockets to choose from and can change the chain length easily by adding or removing links. The newer O-ring chains are quieter and less troublesome than the old chains were years ago.
 

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Discussion Starter · #3 ·
That’s all true but unless someone makes a bolt-in conversion kit...I’m not interested in paying someone to machine this from billet. I have found aftermarket rear pulleys up to 72 tooth but the search engines were so bad it was unclear if these were for an Indian.
I realize a smaller front pulley will wear out the belt quicker but that is acceptable. By simple math a tooth or two change on the front will make a bigger difference than several teeth on the back, and that is what is required here, not to mention that a smaller front pulley will be cheaper than a larger rear.
 

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Discussion Starter · #4 ·
I should say that I have heard of changing the primary gear ratio too - not interested in delving into the crankcase.
 

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I think there might already be a chain drive conversion kit. The belt drive parts to change the ratios would be from non Polaris parts that would require machine shop work.
 

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Discussion Starter · #6 ·
Yeah, I didn’t see any other sizes available on the parts fiche, but made an assumption that someone should be making aftermarket bolt-on replacements just as there are for Harleys. Of course we are talking a huge difference in the size of the market, so maybe that “assume” word has let me down again.
 

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So far the chain drive is for the scout,from zippers,none for the chief yet as they have that screwey cush drive sprokett
 

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If a Chief will pull a trailer, why would it not do ok with a side car?
 

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Discussion Starter · #9 · (Edited)
it pulls the sidecar ok, as you would expect from a motorcycle fitted with a motor that would work well in a D9 Cat, but first gear is way too tall for the kind of slow maneuvering I would like to have (without abusing the clutch as much as I am now). I’ve been on two or three wheels for over 30 years and this is my 5th or 6th sidecar outfit.
I don’t (and would never) tow a trailer with a bike but I don’t think the comparison covers the extra wind drag a sidecar presents, which is huge. The benefits of lower gearing are usually better gas mileage, cooler running and a longer clutch life.
I have been researching this for many hours and have sent out a few email enquiries but I don’t like the chances of solving this without some serious engineering unfortunately.
Another option is to lace a smaller rim on the rear and/or install a lower profile car-type tire, the latter having the added benefits of more traction and much longer life. I would probably go this route before paying for one-off machine-work. I just thought that someone would have done this already...
 

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Yeah the smaller outside diameter car tire is probably your cheapest and safest bet. Considering your rig won't be leaning the darkside tire is more than likely a better tire for that application.
 

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it pulls the sidecar ok, as you would expect from a motorcycle fitted with a motor that would work well in a D9 Cat, but first gear is way too tall for the kind of slow maneuvering I would like to have (without abusing the clutch as much as I am now). I’ve been on two or three wheels for over 30 years and this is my 5th or 6th sidecar outfit.
I don’t (and would never) tow a trailer with a bike but I don’t think the comparison covers the extra wind drag a sidecar presents, which is huge. The benefits of lower gearing are usually better gas mileage, cooler running and a longer clutch life.
I have been researching this for many hours and have sent out a few email enquiries but I don’t like the chances of solving this without some serious engineering unfortunately.
Another option is to lace a smaller rim on the rear and/or install a lower profile car-type tire, the latter having the added benefits of more traction and much longer life. I would probably go this route before paying for one-off machine-work. I just thought that someone would have done this already...
That makes sense, I didn't think of the added drag of a side car compared to that of a trailer.
 

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Discussion Starter · #13 ·
Yes, you have to experience it to believe it. I once installed a 1.5 person chair on a Suzuki GSX1100 G without changing much about the suspension or steering. Above 50 mph it was all I could do to keep it from pulling me off the road. On my first long trip I ended up with both hands bracing one grip to counteract the wind drag after my muscles and tendons gave out! Front end geometry makes all the difference and thankfully the Indian has had the rake/trail modified.
 

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For highway use, wanting more power, a tune using a PV 3 from Dynojet should help. I've seen dyno charts showing a 10% increase in torque across the board with a new tune. Also stage 2 cams increase torque across the board to help with highway speeds. No experience with a side car so no help with gearing or clutch.

before and after dyno charts for a 111 Indian with various upgrades, keep scrolling down.

Dyno Charts - Fuel Moto University
 

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I put a low profile tire on the front of my vintage.i bottomed out a couple of times on stuff im not sure of.i wonder how a low profile tire would do on speed bumps.hope you let us know how that turns out
 
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