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Main Area => General GS500 Discussion => Topic started by: 2wheelin on April 29, 2008, 08:03:55 PM

Title: 47T on a gs ?
Post by: 2wheelin on April 29, 2008, 08:03:55 PM
Hey guys just seen a 47t rear sproket on ebay and was wondering how it would afect the accelaration and top end of a gs500. :dunno_white:
Title: Re: 47T on a gs ?
Post by: bucks1605 on April 29, 2008, 08:07:12 PM
This would have the same affect as going down teeth on the front sprocket. It will make you accelerate quicker and allow you to pop wheelies. Of course it will limit you highway cruising ability, essentially removing 6th gear.
Title: Re: 47T on a gs ?
Post by: 2wheelin on April 29, 2008, 08:07:39 PM
I also found a 43t, and a 48t rear sproket also
Title: Re: 47T on a gs ?
Post by: bucks1605 on April 29, 2008, 08:09:28 PM
I know someone has put a 49 tooth on the rear. A 43 would just be a less dramatic change, many people like to put 41's on the rear.
Title: Re: 47T on a gs ?
Post by: frankieG on April 29, 2008, 08:18:25 PM
i have yet to hear of it done...you could be the first
Title: Re: 47T on a gs ?
Post by: mach1 on April 29, 2008, 08:19:22 PM
can I get a link to these sprockets
Title: Re: 47T on a gs ?
Post by: kml.krk on April 29, 2008, 08:55:47 PM
Quote from: 2wheelin on April 29, 2008, 08:03:55 PM
Hey guys just seen a 47t rear sproket on ebay and was wondering how it would afect the accelaration and top end of a gs500. :dunno_white:
I think this is the correct answer to your question:

http://youtube.com/watch?v=mHdBzgmzMJg

I asked him about the sprockets, he said he's running 47 rear...

cheers
Kamel
Title: Re: 47T on a gs ?
Post by: bucks1605 on April 29, 2008, 09:07:29 PM
Quote from: kml.krk on April 29, 2008, 08:55:47 PM
http://youtube.com/watch?v=mHdBzgmzMJg

cheers
Kamel

I wonder if that helmet would do anything in a crash?
Title: Re: 47T on a gs ?
Post by: frankieG on April 29, 2008, 09:40:16 PM
the helmet looks like a skateboard lid....no one can say you can't stunt on a GS...this guy is good and does our little 500 proud
Title: Re: 47T on a gs ?
Post by: bucks1605 on April 29, 2008, 09:41:23 PM
Quote from: frankieG on April 29, 2008, 09:40:16 PM
the helmet looks like a skateboard lid....

it is  :laugh:
Title: Re: 47T on a gs ?
Post by: mach1 on April 29, 2008, 09:47:14 PM
so is that a power wheelie or clutch ups
Title: Re: 47T on a gs ?
Post by: bucks1605 on April 29, 2008, 09:51:12 PM
Quote from: mach1 on April 29, 2008, 09:47:14 PM
so is that a power wheelie or clutch ups

Looked like a little of both. Slow stuff clutch, and the faster stuff was power?  :dunno_white:
Title: Re: 47T on a gs ?
Post by: darb85 on April 29, 2008, 10:33:39 PM
Quote from: 2wheelin on April 29, 2008, 08:03:55 PM
Hey guys just seen a 47t rear sproket on ebay and was wondering how it would afect the accelaration and top end of a gs500. :dunno_white:

you saw? 

sorry, tense bugs me, english major.  but i think these guys pretty much covered it
Title: Re: 47T on a gs ?
Post by: ohgood on April 30, 2008, 06:10:20 AM
Quote from: bucks1605 on April 29, 2008, 09:07:29 PM
Quote from: kml.krk on April 29, 2008, 08:55:47 PM
http://youtube.com/watch?v=mHdBzgmzMJg

cheers
Kamel

I wonder if that helmet would do anything in a crash?

it would do a nice job of carrying the pieces maybe. wouldn't protect much though.

the guy has skill, no doubt. and he's either fabbed a really nice set of case guards or has a source I haven't seen before. I WANT THOSE. they look beefy enough to do the job, and maybe double as hiway pegs ;)


Title: Re: 47T on a gs ?
Post by: pjm204 on April 30, 2008, 06:15:53 AM
He says it is a homemade crash cage, looks really nice.
Title: Re: 47T on a gs ?
Post by: dgyver on April 30, 2008, 09:18:44 AM
Quote from: 2wheelin on April 29, 2008, 08:03:55 PM
Hey guys just seen a 47t rear sproket on ebay and was wondering how it would afect the accelaration and top end of a gs500. :dunno_white:

You would lose about 25 mph from your top speed... 110mph at 10,5k. Highway speeds would be around 6-7k rpms.
Title: Re: 47T on a gs ?
Post by: mach1 on April 30, 2008, 10:14:16 AM
what about a 13t front and stock rear? Im assuming a 106 link chain is neede but can I use my 108 link? dont care much about highway dont ride it that often.
Title: Re: 47T on a gs ?
Post by: gsJack on April 30, 2008, 01:14:51 PM
.851(23/27) x 47/39 = 1.02

Would be about the same as riding down the highway in 4th gear if you want to try it.  GS500 redlines at over 100 mph in 4th gear, makes a nice passing gear.

(http://img.photobucket.com/albums/v443/jcp8832/GS500gearing-rpms.jpg)

With standard 39/16 sprockets engine rpm in 6th is 4730 rpm @ 60 mph.

4730 x 47/39 = 5700 rpm @ 60 mph with 47/16 sprockets.
Title: Re: 47T on a gs ?
Post by: gsJack on April 30, 2008, 01:43:56 PM
Quote from: mach1 on April 30, 2008, 10:14:16 AM
what about a 13t front and stock rear? Im assuming a 106 link chain is neede but can I use my 108 link? dont care much about highway dont ride it that often.

16/39T and 110 link center distance is 25.679"

14/39T and 110 link center distance is 25.975". 

14/39T and 108 link center distance 25.347"

13/39T and 108 link center distance 25.494"

Center distance should be OK with 13/39T and 108 link chain but I'd be more concerned with cutting thru the rubber block and cutting the swingarm in half.  Better to go up some in the back.  Besides, the chain/tooth action gets worse as you get further below 16T, teeth get undercut too much.
Title: Re: 47T on a gs ?
Post by: Ronin on April 30, 2008, 01:49:36 PM
This winter I put a 44tooth on and a 17tooth up front,for a final ratio of 2.59.Basically it's like having a 15 tooth up front.
The reason I did it was mainly for looks.I polished out the rear sprocket and it looks great.I have always thought the GS rear sprocket looked like it belongs on a moped.Plus with the 17t up front means less stress on the chain. :cheers:
Title: Re: 47T on a gs ?
Post by: 2wheelin on April 30, 2008, 08:57:28 PM
mach1 here is a link for the sprokets i foundhttp://motors.shop.ebay.com/items/GS500_W0QQ_nkwZGS500QQ_catZ6028QQ_pcatsZ6000QQ_pgnZ2 (ftp://http://motors.shop.ebay.com/items/GS500_W0QQ_nkwZGS500QQ_catZ6028QQ_pcatsZ6000QQ_pgnZ2)
Title: Re: 47T on a gs ?
Post by: 2wheelin on April 30, 2008, 09:02:32 PM
I also have a 15t front sproket on my bike and wont a little more but dont want to go down in the front any more than I have. I was wondering what size rear sproket would be good to use with the 15t. I dont do much highway rideing so thats not an issue.
Title: Re: 47T on a gs ?
Post by: dgyver on May 01, 2008, 03:46:15 AM
I normally run a 15/41. I was looking last night if I had a 40 to try for a while. I avoid straight roads whenever possible.

I have a gearing/speed spreedsheet that I use for gearing selection at the track. I got it from EvilPumpkinRacing's website but I do not see it on there anymore. Let me know you want me to email it to you.
Title: Re: 47T on a gs ?
Post by: beRto on May 02, 2008, 07:56:24 AM
Quote from: dgyver on May 01, 2008, 03:46:15 AM
I normally run a 15/41. I was looking last night if I had a 40 to try for a while. I avoid straight roads whenever possible.

I have a gearing/speed spreedsheet that I use for gearing selection at the track. I got it from EvilPumpkinRacing's website but I do not see it on there anymore. Let me know you want me to email it to you.

If it's of any use, I made a gearing/speed spreadsheet that is tailored to the GS. Details here:
http://gstwins.com/gsboard/index.php?topic=41123.0 (http://gstwins.com/gsboard/index.php?topic=41123.0)

It's also in the wiki:
http://cgi.stanford.edu/~sanjayd/gs500/Main/GearingCalculator (http://cgi.stanford.edu/~sanjayd/gs500/Main/GearingCalculator)

:)