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got a gearing question.

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I want to put a smaller sprocket in the rear of my sm but I don't know if the bike will pull it or not. on the high way it gets real buzzy and i would like to lower the over all rpms on high way.ok heres the specs.36 bsr w/dj kit procirut header,white bros e2 pipe.3x3.16thooth counter sprocket.and i do a lot of 2 up riding i weigh 175 and passanger weighs 130.please those who may have simmaler setups please give me some insite wether i should run a 39,38 or gasp37.i have to have sproket made because im running cbr f2 wheels.thankes and please honest insite i still want my bike to get up and move but be anle to cruise the highway and i know theres some:ride: middle ground in there somewhere.

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I want to put a smaller sprocket in the rear of my sm but I don't know if the bike will pull it or not. on the high way it gets real buzzy and i would like to lower the over all rpms on high way.ok heres the specs.36 bsr w/dj kit procirut header,white bros e2 pipe.3x3.16thooth counter sprocket.and i do a lot of 2 up riding i weigh 175 and passanger weighs 130.please those who may have simmaler setups please give me some insite wether i should run a 39,38 or gasp37.i have to have sproket made because im running cbr f2 wheels.thankes and please honest insite i still want my bike to get up and move but be anle to cruise the highway and i know theres some:ride: middle ground in there somewhere.

Wow, you already have a 16t cs sprocket and you want to go higher? I can't imagine going any higher than the 16/41 you have already.

How fast do you cruise on the highway with 2 up?!!

You might need a completely different bike for your purpose of riding 2 up.

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Wow, you already have a 16t cs sprocket and you want to go higher? I can't imagine going any higher than the 16/41 you have already.

How fast do you cruise on the highway with 2 up?!!

You might need a completely different bike for your purpose of riding 2 up.

sorry forgot a variable i'm running a 43 in the rear the was the smallest i could go with a 520 conversion sprocket with out having it special made the cbr was 530 pitch

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oh ya got a another q at 16/43 on a 150/60r17 tire about how many rpms drop per thooth lost in the rear thanks

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sorry forgot a variable i'm running a 43 in the rear the was the smallest i could go with a 520 conversion sprocket with out having it special made the cbr was 530 pitch

If it's me, I wouldn't go any lower than a 41t rear. The 16t front makes a lot of difference. :ride:

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16/43 is VERY close to stock tard gearing of 15/41

You might be able toi pull something higher but I doubt it. You'll be downshifting all the time on hills, and it won't pull redline in top with 300lbs on it...

You're going to need more motor.

IMO you're asking a bit much of the bike. It was never designed to tote that much weight that fast for that long

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+1 to the last to statements :ride:

15/41 is the best all around gearing for the DRZSM IMHO.....I was 15/38....and now went back to 15/41:thumbsup:

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You are probably about as good as it gets. If you go smaller you won't have enough power. 16/41 would be the limit (bought the same as 15/38) but you aren't far off it now.

I think if you dropped it anymore you would be disappointed with the 2 up and the highway. You'd fall off the power and end up slower.

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You are probably about as good as it gets. If you go smaller you won't have enough power. 16/41 would be the limit (bought the same as 15/38) but you aren't far off it now.

I think if you dropped it anymore you would be disappointed with the 2 up and the highway. You'd fall off the power and end up slower.

well if needing more motor is the deal breaker how much to pull 16/38 gearing,will converting to 39 fcr do it,or a athena 434cc kit,or how bout a cvk41 carb and stage 1 hot cams

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will it pull decent with 2up and pull hard solo with 16/39 gearing?

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I was running an S engine, stage 2 HC's (in & ex) Muzzy and a 39 FCR. I would consider it adequate with 15/38 (16/41) with SM rims. I ran 75 ish to and from work. It would have been tough 2 up. Granted they all drive like freaks here, so I liked having some oomph left over.

16/38 is too much. I wouldn't even go there now with the 470.

Try the Sprocket specialists website you may be ably to cross over the sprocket part number you currently have to a 40 - 42. I have the same problem as there is not alot of selection for a GS500. I have been happy with this gearing for SM though so I haven't monkeyed with it too much.

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what was rpm like at 75 when im at 65mph im just under 6500 rpm and that just seems hight to me and hard on th engine and sprocket specialest is the way i was planing on going but it is still 80 bucks a sproket

over all i just want to lower the rpms on the highwayit only has to pull hard solo .

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with SM 17inch wheels the "highest" you can go is 16/38

for MAX speed with a stock or just bolt-ons stick to the stock 15/41 becouse the motor runs out of tork

I run a 16/41 and injoy my 85mph top speed

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what was rpm like at 75 when im at 65mph im just under 6500 rpm and that just seems hight to me and hard on th engine and sprocket specialest is the way i was planing on going but it is still 80 bucks a sproket

over all i just want to lower the rpms on the highwayit only has to pull hard solo .

Right around there (6800?) I think. I haven't ridden much over the last 2 months. These thing run all day at 7K though no need to worry about it at all.

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My 07 Sm has the fcr,3x3,434 CW kit,full yosh,and hot cams.I weigh 205lbs and have 15/38 gearing.The bike pulls real nice and is just about perfect for me on the highway at 75 MPH.I wouldnt go any taller than 15/38 even with these mods.....

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Don't gear it any higher... you'll regret it. :ride:

I have a stock engined SM, weigh 130, and never ride double...

...and 15/39 is plenty high for freeway cruising.

It ain't a Harley, ya know... :ride:

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I run 16-41 on my SM, and run mostly highway to and from work, and am very happy with the gearing of it...Granted I have done bb, porting, fcr, pipe, 3x3 and cams. Here's a useful link to figuring out the effect of gearing changes;

http://www.gearingcommander.com/

Cheers.

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