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Discussion Starter · #1 ·
Well i got my 45t rear sprocket for my 03 speedy today and it doesn't fit with the stock chain (it was a mixed review if it would fit, so i knew it was a 50 50 shot) :(. So my question is do i buy a new chain or buy a 17t front sprocket (stock is 18t), My chain is showing no signs of being wore out and it would be a pitty to spend all that money for a chain then ended wanting the 17t any ways. I have done a ton of reading on this it seems that the 17/45 combo gives a 14% increase in over all torque and makes for a hell of alot of fun. The down side would be it puts you in high rpms when cruising down the highway and lose top speed but i dont care about that (no need for 160mph). From what i understand 18/45 is a good middle ground. But how big of a difference am i going to feel from going from 18/42? For $50 it was worth gambling trying out 18/45 but im not wiling to gamble another $150 for a chain to find out.
 

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Get the 17 up front, seems like your only option really. From what i've been researching the difference in feel of either a 2.47 (17 up front 42 on the back) or 2.50 (18 up front with a 45 up back) would be minimal.

stock = 2.33
17-42 =2.47
18-45 = 2.50
17-43 = 2.52

(someone who has been doing more than reading about ratio's please chime in here)

Can you return the 45T and get maybe a 43T and run that with a 17 up front?
 

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That sucks , I just did the same thing on my 06 speedy and the stock length chain worked great with the stock front sprocket and the 45T rear .
Are you sure you got as much slack as you can get ?
Did you try fitting the sprocket into the chain then mounting it to the wheel ?
That is what I had to do and I ended up with a fair bit of room to adjust the slack properly.
 

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Well i got my 45t rear sprocket for my 03 speedy today and it doesn't fit with the stock chain (it was a mixed review if it would fit, so i knew it was a 50 50 shot) :...
It won't go over the sprocket after it has been installed
Try this:
Adjust the chain for max slack;
remove old sprocket;
slip chain around sprocket and THEN slip the sprocket onto the carrier & bolt it up
That worked for an 07 I helped one of the local guys install a 45 on - there was no way chain would go over sprocket once already installed on the carrier. But with this method it went on & was able to still adjust out slack to the correct tension.

edit - ah I see that is same method dieselg33k has suggested above - beat me to it!
 

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Discussion Starter · #5 ·
ill give it another try. Ill try to put the chain on the rear, then the front and see if that makes a difference. I turned the adjustment as much as it could go or atleast as much as i think it can go, it doesnt seem to want to move any closer.

hmm some times having a ton of decisions sucks, as much as having none lol
 

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Discussion Starter · #7 ·
i tried everything and its about a 1/4 or less from fitting :(. I was putting the chain on the sprocket first then, putting the sprocket on the wheel. What you guys think adding a link or 2? Can you even buy single links from a motorcycle shop? What do they do with all the links they have left from cutting chains to size?
 

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You should replace your chain and sprockets at the same time anyway. Just get the new chain.
 

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Discussion Starter · #9 ·
i know i should but i just dont like wasting money, my chain has no sign of wear and nether do my stock sprockets. The only reason for the gear change was bcs i wanted more bottom end. I guess my question should be is 17/45 really to low? Sorry for my ignorance with gearing, my previous bikes were belt driven (buells). Im learning as i go.
 

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Discussion Starter · #10 · (Edited)
Well im going with the 17 and if i dont like it, that means ill be buying a new chain for 18/45 setup. That seems like my smarts option. thanks for your help guys. By chances do you know what your stock chain length was? I know mine is 106
 

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Have you tried the gearing commander web site ? From what I have heard you will not like the 17/45 . Too low for highway use , your mpg will tank right out .
I know you have tried but have you tried moving everything ? One tooth this way or that ? Moving the wheel ? Can you post a pic of how close you are to getting it to fit. ?
 

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Discussion Starter · #12 ·
i see what i can do about a pic, my garage is kinda dark but i think i can figure somthing out. Ill have a pic up in a few mins
 

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Well I guess that does it .
If I were in your situation I would go to the 17 F
Use up the chain and rear sprocket and when they are finished get a new chain and put your old 18 f and 45 r with the new chain.
Just keep an eye on the wear strip.
Sorry about your luck.
It is too dark out for me to count my links tonight
If no one else gets you the answer by the morrow I will post up my numbers
 

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Looks like your doing it as suggested If you want a extra link I'm sure I have some I saved. I can also get you a new chain for around 110.00 or so. I would personally get a 17 front. 1 tooth on front is like 3 on the rear which would be a riot.
 

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Discussion Starter · #16 ·
about how bad you think my mpg would go down? I havnt done enough riding to even to know what im getting know, only been through one tank and most of that tank was used up letting the bike warm up bcs it was so dam cold outside. During the one week of nice weather we got here i was waiting on stupid brake caliper bolts bcs of the shop who put my tires on!! :mad:
 

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13.5% difference overall with the 17/45 combo
with 17/42 you are looking at 7.6 %

so at 110kph in 6th 17/45 = 4670rpm
@ 110kph in 6 17/42 =4300rpm
stock 18/42 = 4100 rpm
I am now running the 18/45 combo = 17/42 the milage drop and rpm range will not be too big a deal . From what I have heard those who like to spend all day on one wheel and dont spend any time on a highway like the 17/45 . Most others dont like it .

How did that brake thing turn out for you ?
I got these numbers from here http://www.gearingcommander.com/

play around in there m see what you can figure out .
 

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do it

i swear your mileage wont be much of an issue. my sprint seems to get better mileage with the lower gearing. runs about 5k at 70mph. depends on the day but i get 50 mpg some times and normally run 70-90 mph. the smile you will have from low gears will kill the poor mileage if it happens.
 

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I wouldn't worry about mileage ride the thing 17/45 and have some fun for a while at least get your monies worth then change it to 18/45 with a new chain next year and claim back some MPG.

Russ
 

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Discussion Starter · #20 ·
well i made up my mind. I went on a 50mile ride today out in the country and in town. I figured out a few things man do i love the sound this thing makes! :), i defiantly felt like the power was way to high up and i think the stock bars ether have to much back sweep or just a little to tall bcs my right shoulder(i broke my collar bone a few yrs ago and it wasn't set completely straight) felt like it was being pushed on. Back to the gearing, im going to buy the 17 front and try 17/42 which is pretty close to 18/45 and if i feel like i want even more low in power i all was got the 45 for 17/45 :motorbike2

Thanks again for all the help
 
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