Replacing Front and Rear Sprockets Question

I believe this is what you need. Please double check the hole pattern before ordering though... www.z1enterprises.com/product/BAJTR488-43

Edit:

Did some figuring and I think you would be better off with an 18/45 combination if available. A 530 chain 18 tooth sprocket is about the same diameter than your original 15 tooth 630 sprocket. A 17 tooth 530 front is smaller.

Nessism wrote: I believe this is what you need. Please double check the hole pattern before ordering though... www.z1enterprises.com/product/BAJTR488-43

Edit:

Did some figuring and I think you would be better off with an 18/45 combination if available. A 530 chain 18 tooth sprocket is about the same diameter than your original 15 tooth 630 sprocket. A 17 tooth 530 front is smaller.

Oh man thanks Ness that is killer! Will certainly look into options for the 18/45 but the big deal breaker will be $$, whichever is cheaper will be the route I will need to take. Single income family makes this a bit more challenging hahaha

Brett

Irish-Kawi wrote: Well bit of an update here to clarify a few things now that I have been able to get back on the bike and ride her again.

So with the current stock 630 chain setup and 15T front and 38T rear sprocket I end up cruising at 60mph at 4000-4100 rpm's which is just awesome and so easy on the rider and bike. At 70mph I am hitting about 5000rpms dead. It still has a ton of zip off the line but I really don't want to give up the ease of cruising and how nice the lower RPM range is. I think going to a 17T 530 pitch front sprocket with a matching 43T 530 pitch rear sprocket will alter it very nominally and stay MOSTLY in the same range that I currently have. I suspect it might raise it 100-300 or so rpm's with the slightly "Taller" front gearing which will have a noticeable seat of the pants affect on acceleration off the line, but will maintain a mostly stock gearing with all the benefits of the 530 chain making it quicker and a bit snappier due to the lighter reciprocating mass and slightly taller front gear.

So that being said, unless some new information comes to light I likely will end up with a 17T 1/4" offset 530 pitch front sprocket from PBI, a 111 link 530 gold X-ring chain, and now just need to source a 43T 530 pitch rear sprocket that will fit correct on my NA 85 GPz750. If anyone is able to help locate the rear sprocket that meets these specs truly would appreciate it!

Thanks,
Brett

Ok, the bad news is the most Kawasaki speedos read about +10mph fast at 100mph and at an indicated 60mph, you might really only be going 55-57mph.

If you drop your gearing to the point that 1st becomes like a "Granny Gear" is that really giving you faster acceleration than you get with a more stock gear and just giving it more revs and slipping the clutch a bit to get going? It seems that extra gear change with low gearing that you'd have in some circumstances might be working against you? I know some do seem to run lower gearing for the drag strip etc. but even so there seems a point where it could start to do the opposite of what you are trying to do and also we rarely launch our bikes in the same manner as we would at the drag strip on the road. The higher performance bikes also have higher lift cams and features that require more rpm than a stockish machine.

I know it's each to their own, but if you have a 5th gear that's reasonably relaxing for cruising, there are plenty of other gears you can change down to when at 60 or less to give you reasonably "neck snapping" acceleration.

So I think staying close to stock is advisable, particularly until you get to ride it some more, on my KZ1000 the chain was pretty worn when I got it and I was pretty cautious about riding it far, or fast. So I needed the new chain etc, asap, but at the same time didn't have enough experience to really know what ratio to go with, So far it seems great,but I still need to ride more and high up in the mountains to be certain, one thing about going with the 18/40 combo was I figured I could drop to a 17T front easily enough, with out having too small a diameter sprocket for the good of the chain, if 2 up and higher altitude ever made it necessary. Front sprockets are also pretty easy to swap in and out as circumstances dictate, if you do end up needing the best of both worlds to fit your needs.

good luck in finding 18 tooth 1/4 " offset coutershaft sprocket thats off the shelf.they can make them for you .more money and time.

if you want to compare sprocket diameters . also chain length.
here is the calculator..................................... www.rbracing-rsr.com/calcsprocketdiam.html

Thanks everyone really do appreciate all the help. I am talking to a "company" (its a hobbyist who has CNC machine and does some work on the side) called 7th Gear Designs with the owner named Jim. Really nice guy and very smart too, was referred to him on another of the Kawi boards that I am on. He makes both front and rear sprockets and can do anything I want basically. Currently have a request out to quote what it would cost to do a 18T 6mm offset front sprocket and 45 tooth rear sprocket and seeing what he can do with that. Wondering if maybe a "packaged" deal would lower cost or what. In a perfect world I would rather support small business/hobbyists like this especially since he is also a Kawi GPz rider himself, albeit a turbo GPz750 hahaha. Time will tell and cash will be the big decider here but will see what I can find out. Once I find the right info will share here to help anyone else wanting to do what I did.

Brett

kawi810 wrote: if you want to compare sprocket diameters . also chain length.
here is the calculator..................................... www.rbracing-rsr.com/calcsprocketdiam.html

Awesome thanks Kawi, one question though... what is the center to center measurement for our 85 GPz750's? I know the pitch, and tooth count front and rear, but not sure where to locate info on center to center, and not wanting to crawl under the bike outside in the snow can measure myself at time of posting.

Brett

about 25.5" depends on adjustment .

kawi810 wrote: about 25.5" depends on adjustment .

Thanks man appreciate it

Brett