83GS550E Sprocket Size For Increased Speed/Lower RPM?

[Old Colt]

My 83 originally got about 55 MPG, with a larger sprocket up front I got 63 if I recall.
That bike will pull to about 120 and if you reverse the speed/ rpm from there I expect something is amiss with your tach or speedo. Been to long since I rode mine to recall and details and it is so far from stock now that I may never remember.
Either that or there is a 14 tooth on the front of it.

[C.V.]

consider the noise could come from any loose parts on the bike (when riding) and not necessarily the engine

i chased a hight pitch rattle for months before discovering it was the rectangular suzuki logo plate on the lower tripple tree cover - the plate was glued and in place and all LOOKED good yet it rattled anoyingly loud at cca 5krpm.
i took the plate off, cleaned off the glue and used silicone instead.
no more rattles


a good carb sync helps as well

Ha, mine is worse. I had an intermittent high piched shimmery, kind of chimey noise that i obsessed on for a coupla weeks. It finally went away when I took 3 of the four keys off my keyring! DOH!

[GQROD]

My 83 originally got about 55 MPG, with a larger sprocket up front I got 63 if I recall.
That bike will pull to about 120 and if you reverse the speed/ rpm from there I expect something is amiss with your tach or speedo. Been to long since I rode mine to recall and details and it is so far from stock now that I may never remember.
Either that or there is a 14 tooth on the front of it.

Thanks for your advice

I counted the rear sprocket teeth and it has 112 on it.

Seems like a lot to me but this being my first bike i would not know what is stock.

I will have to pull the front cover off to see how many teeth are on the front sprocket.

The noise is what is killing me since it went away when i put the first starter in ( new oem )

Then i got a starter back (since the replacement blew from an electrical problem...since fixed.) and installed it then the noise came back.

The noise sounds like knocking but i don't think it's a bent rod since it does not happen unless it's in gear while riding and between 3000 to 4000 RPM so this either something i will have to live with or trap the gremlin that is messing with my head.

Pulled the stator cover off and nothing seems abnormal, nothing broken nothing rubbing odd.

[GQROD]

Ha, mine is worse. I had an intermittent high piched shimmery, kind of chimey noise that i obsessed on for a coupla weeks. It finally went away when I took 3 of the four keys off my keyring! DOH!

I wish it were this easy i don't mind feeling silly over a simple problem but knocks and rattle would scare anyone while riding!

[MelodicMetalGod]

Thanks for your advice

I counted the rear sprocket teeth and it has 112 on it.

Seems like a lot to me but this being my first bike i would not know what is stock.

I think 112 is probably incorrect. Stock is around 48 for these bikes.

A little reference:

http://www.bikebandit.com/suzuki-motorcycle-gs550esf-1985/o/m6075

Best of luck!

PS: Of course, if you do actually somehow have a 112 on the rear, that sure would explain the gas mileage and the low speed.

[GQROD]

I think 112 is probably incorrect. Stock is around 48 for these bikes.

A little reference:

http://www.bikebandit.com/suzuki-motorcycle-gs550esf-1985/o/m6075

Best of luck!

PS: Of course, if you do actually somehow have a 112 on the rear, that sure would explain the gas mileage and the low speed.

YES i counted the sprocket teeth TWICE! i knew something was up because i thought it should have been no higher than 50t if that.

Now just so i'm not crazy you do have to count EACH tooth correct? The sprocket measures 10 inches wide.

Why would anyone want to put a 112 tooth sprocket on a bike??? ok i think the PO used this bike as a STUNT bike, which explains the sprocket being so big and all the road rash on both sides of the bike, and cracked plastic.

The PO must have been racing against mini bikes and thought he needed an edge.

WOW this is getting weirder and weirder!

[MelodicMetalGod]

112? Really? Holy Toledo!!!

I'm by no means a major gear head compared to many folks here, but I've read a LOT over the last few years about sprocket sizes and projects and I've NEVER seen a number that massive for a rear sprocket.

Wow. Guess it's a good thing you looked into that.

Hey, would you mind posting a pic here? I'm curious how that looks on the bike.

[Old Colt]

A 112 tooth sprocket would be 22.28" diameter.

112X.625/3.14159

[MelodicMetalGod]

Is it possible that there's a non-standard chain and sprockets on the bike that would include more but smaller teeth on the sprocket?

[Old Colt]

The original 48 tooth sprocket would have a PCD of about 9.5", that would be an OD a bit over 10".
If he double counted the teeth he might have a 56 tooth on the back. That would rev a bunch more than we are used to on these bikes.

[MelodicMetalGod]

Well, looking at the pic in GQRod's sig, it looks like a normal sized rear sprocket. Something doesn't add up here. That's why I was wondering if there might be a sprocket chain combo that would have a rear sprocket with 112 much smaller teeth...?

[GQROD]

I counted each tooth ( now three times. ) HOWEVER i looked on the sprocket and saw 48-530 ! stamped on it.

It must be a front sprocket that is too small. I will take the cover off tomorrow and see.

Measured the widest points and got 10 inches wide

I'll post pics tomorrow

The math in the prior post has me thinking maybe i'm counting it wrong. But that's what i counted.( ok now i'm weird ! )

[Old Colt]

Use a paint marker or a sharpie to mark one tooth on the sprocket.
I could see the chain having 112 teeth but the sprocket will not be far away from the original 48. A quick look at the picture of your bike shows it to not be something radical.

[GQROD]

Thanks everyone i edited my prior post to show i saw 48-530 stamped on the sprocket.

Must be the front one is smaller.

Can the front sprocket being smaller by only one tooth really make that big a difference?

Should i go with a smaller rear sprocket and front combo?? for better mileage and top end ? Any recomendations on which brand and vendor ?

Thanks all

[p_s]

112 is the stock number of links on the chain. Maybe that's what you were counting?