530 conversion w/GS1100E swing arm, 17T or 18t, Vortex sprockets??

[Chuck78]

I'm swapping on a GS1100E swing arm onto my 77 GS750B soon, and have a 120 link RK gold 530 O-ring chain. Stock 630 gearing was 15-41, which in a 530 at least ratio-wise equates to an 18-49 almost exactly. I wouldn't mind a little better acceleration, so bumping it up slightly with my 140/70-18 tire into the equation,
*stock 630 with 110/90-18 and
15-41 @ 70mph = 5145rpm
*530 chain with 140/70/18 and
18-50 @ 70mph = 5259rpm
*530 chain with 140/70/18 and
17-48 @ 70mph = 5346rpm


I am pondering the extra clearance of an 18T front sprocket from banging into my nice alloy swinger if the chain gets slightly loose and goes unnoticed, vs the slight rotational weight savings of a 17-48 setup with a slight bit less clearance.

Can anyone advise me on if a 17T 530 has enough clearance to a GS1100E box aluminium swing arm, or if I need to be shopping for an 18-50 setup?

Also any opinions on an extra 100rpm's at 70mph vs an extra 200 rpm's. The inline 4's seem balanced really well, and the GS550 with a much more aggressive gearing seems fine to me cruising at 5500rpm all day long (although the wide valve duration angle combined with Emgo "Dunstall style" glasspacks really does a number on the ears after an hour or three), but wondered what anyone else thought. It is closer to the peak torque output of the engine!

[Chuck78]

Also, I am looking at getting a Vortex 3521-17 or -18 front sprocket - as I have seen them listed for our bikes, but mostly GSXR's and Bandit's. I assume they will work fine, but that I will still probably need the 6mm spacer that aftermarket sprockets need to run in place of oem??? Anyone have an ebay link handy to guide me towards this spacer? I think the OEM sprockets have some vibration dampening washer/spacer setup on both sides of them that the aftermarket units don't, so you need this spacer apparently. Any input???


Also looking at JT's JTR816.48 sprockets vs Sunstar 48's. It is hard to find a real photo of the JT's, most say "stock photo, actual item may vary in color etc" and obviously aren't at all the right bolt pattern or anything. Most say in the JT "may come in black or silver, we have no control over the color that is shipped to us."

[Chuck78]

This is the JT I would hope for, looks totally different than any of the "stock photos:"


or a rare SunStar in black, most show silver in the ebay auctions:

[Jedz123]

You know whats funny is if you want to save $$$ that Bandit (GSF) Sprockets mount on GS rims... I mounted a 14 tooth front and 44 tooth rear on a couple GS 750 and 1100 bikes... Food for thought

Also I almost always gear -1 tooth down in the front. Might sacrifice some Mileage but you gain so many more smiles

[Chuck78]

Aha... Supersprox! looks like aluminium center and steel outer with forged rivets, not bad for $90, and it's Black and Gold!!! I wonder the weight savings vs a standard SunStar or JT steel? Is it worth an extra $40-50? The black and gold really is on the brink of swaying me. Application for 95-05 GSF1200 Bandit is the same front and rear for our GS series apparently. Thanks for the tips guys.

[Chuck78]

Well it's between $40 for that black steel SunStar, or $95 shipped for the black and gold aluminium/steel SuperSprox... Leaning towards the SuperSprox. I skipped on some $300-$400 rear shocks because they are an easy bolt on. With no center stand and a borrowed motorcycle lift to do the wheels/brakes/forks/swingarm, I think I may opt to do the better sprocket now with the rest of the drivetrain and just put in a few more hours of overtime than usual

EDIT: Just ordered a Vortex 17T front and the 48T SuperSprox rear, might as well since my lovely wife got me the top top of the line RK 530 O-ring chain for my birthday, and I already have gold brake rotor centers, might as well complement the gold RK chain and gold rotors with a black and gold sprocket! Motivation to ditch the stock green painted 4.8 gallon tank and go with the later L model teardrop shaped tank which I prefer the look of, and PAINT IT BLACK!

[Chuck78]

Am I going to need this 6mm spacer still then? I assume so. I'll check at the local VJMC junkyard first but may have to place a $3 order from Z1 just for that.

http://www.z1enterprises.com/ItemDetails.aspx?itemDescription=Front+Sprocket+Spacer+Washer+-+6mm&item=EM95-49014-1

To clarify for anyone stumbling upon this, doing a 530 conversion or running non-OEM sprockets, Z1/Emgo says: "This washer goes on the OUTSIDE of the sprocket! Not between the case and the sprocket. The early GS series bikes came equipped with a countershaft sprocket that was sandwiched in rubber. Use this in place of that rubber."