Chain size

Im looking to go down on my rear sprocket and up on my front sprocket on my kz750 twin . Dumb question but whats the width difference in the 530 and 630 chain . Im running Harley shocks so my current chain is extremely close to the bottom of the shock . Most sprockets ive seen use the 630 chain which I fear might be too wide and cause contact with the shock . thanks

They are both 3/8" wide.
chain dimensions

whats the difference then between the two? Some sprockets use the 630 and some are listed 530 . This questions me .

650ed did a great job of describing the chain numbering system just the other day. look at
www.kzrider.com/forum/5-chassis/591732-5...-520-sprocket-advise

Schmeck wrote: whats the difference then between the two? Some sprockets use the 630 and some are listed 530 . This questions me .

If you look at the chart I linked to, the pitch (distance between rollers) is smaller, and the rollers are correspondingly smaller for the 530 chain
.........pitch.......roller diameter.....width
530... 5/8"...........0.400"...............3/8"
630... 3/4"..........15/32"................3/8"

Okay After searching around Im begining to understand . Only question I really need to know now though is if Im running a 630 chain and 32 tooh rear sprocket , whats the most teeth I can put on the front ? I see alot of discussion on 530 and 520 chain but not much on 630 , unless Im reading forums wrong . My intentions are more top speed and less acceleration . I like to cruise more than take off . Also From what I see the 630 is stock chain size so I should probably see a good difference just changing the rear to 32.

Schmeck wrote: Okay After searching around Im begining to understand . Only question I really need to know now though is if Im running a 630 chain and 32 tooh rear sprocket , whats the most teeth I can put on the front ? I see alot of discussion on 530 and 520 chain but not much on 630 , unless Im reading forums wrong . My intentions are more top speed and less acceleration . I like to cruise more than take off . Also From what I see the 630 is stock chain size so I should probably see a good difference just changing the rear to 32.

These engines were born to spin at their designed road speeds, and they happily do so.

Ideally, there's a sweet spot where the engine is performing at maximum efficiency, where the rpm is "just right" for the load and road speed. And neither over-revving (such as constant cruising in a lower gear), nor under-revving (such as more lugging effort resulting from too tall gearing).

Stock gearing usually produces the better compromise between acceleration and cruising.

Consider that the maximum road speed of a stock Z1 is about the same in either 4th or 5th gear.

Imo, ideal highest gearing produces top speed just as engine rpm meets red-line.
In other words, where a properly performing engine will barely pull red-line in top gear.

As known, taller overall gearing may require less rpm for a more relaxed feeling at cruising speeds, but at the expense of reduced acceleration. And usually doesn't increase attainable top speed.

Conversely, lower overall gearing may afford quicker acceleration, but at the expense of a more frenetic unnecessarily higher rpm at cruising speeds.

However, taller gearing doesn't necessarily result in higher mpg. And may result in lower mpg.

Where the engine is running in its sweet spot at a given cruising speed, changing to taller gearing that moves it out of its sweet spot -- although at a lower rpm -- requires the engine to work harder at the lower rpm, and actually perform less efficiently.

Just my 2¢.

Good Fortune!

Schmeck wrote: Okay After searching around Im begining to understand . Only question I really need to know now though is if Im running a 630 chain and 32 tooh rear sprocket , whats the most teeth I can put on the front ? I see alot of discussion on 530 and 520 chain but not much on 630 , unless Im reading forums wrong . My intentions are more top speed and less acceleration . I like to cruise more than take off . Also From what I see the 630 is stock chain size so I should probably see a good difference just changing the rear to 32.

I have a 1979 KZ 750 twin. The stock gear ratio is 16/38. You can go up to a 17T front and still have barely enough room to clear the chain guard in the front. 18T will not fit with guard in place. Most people run the 17T/38 ratio (I am right now) and it's OK for city but IMHO, the engine just screams on the freeway which I no longer ride on anyway.

back when I commuted on the expressway, I ran a 16/32 ratio for about 20 years. It had enough acceleration for me but I only weighed 160 and never carried anything else. It lowered the RPM to about 3600 at 60 mph. IMHO, a best "all around" ratio might be about 17/36 but anything other than a 38T rear means you have to buy a custom rear sprocket and they are PRICEY. Close to $100 delivered last time I priced one. The stock steel 38T rears can be had for about $25.

NOTE:

I should probably see a good difference just changing the rear to 32.

When I ran a 32 rear, the chain clacked against the swing arm sometimes, the diameter is too small. Also, I had to shave metal off the rear wheel hub to allow clearance for the heads of the chain rivets. Using a 17T front and a larger rear will save the hassles.

Patton wrote:

Schmeck wrote: Okay After searching around Im begining to understand . Only question I really need to know now though is if Im running a 630 chain and 32 tooh rear sprocket , whats the most teeth I can put on the front ? I see alot of discussion on 530 and 520 chain but not much on 630 , unless Im reading forums wrong . My intentions are more top speed and less acceleration . I like to cruise more than take off . Also From what I see the 630 is stock chain size so I should probably see a good difference just changing the rear to 32.

These engines were born to spin at their designed road speeds, and they happily do so.

Ideally, there's a sweet spot where the engine is performing at maximum efficiency, where the rpm is "just right" for the load and road speed. And neither over-revving (such as constant cruising in a lower gear), nor under-revving (such as more lugging effort resulting from too tall gearing).

Stock gearing usually produces the better compromise between acceleration and cruising.

Consider that the maximum road speed of a stock Z1 is about the same in either 4th or 5th gear.

Imo, ideal highest gearing produces top speed just as engine rpm meets red-line.
In other words, where a properly performing engine will barely pull red-line in top gear.

As known, taller overall gearing may require less rpm for a more relaxed feeling at cruising speeds, but at the expense of reduced acceleration. And usually doesn't increase attainable top speed.

Conversely, lower overall gearing may afford quicker acceleration, but at the expense of a more frenetic unnecessarily higher rpm at cruising speeds.

However, taller gearing doesn't necessarily result in higher mpg. And may result in lower mpg.

Where the engine is running in its sweet spot at a given cruising speed, changing to taller gearing that moves it out of its sweet spot -- although at a lower rpm -- requires the engine to work harder at the lower rpm, and actually perform less efficiently.

Just my 2¢.

Good Fortune!

Problem is the stock gearing spins 5K RPM at 70 MPH and that is NOT a happy place to cruise. The twins have internal balancers but they are far from perfect. You will get tired really quickly hanging on to that thing screaming down the highway. The wide torque band on the twin makes it very happy at lower RPMs, even when mine was pulling a large windshield (AIR BRAKE) that increases drag. Gas mileage was about the same running the 16/32 on mine, but comfort level was tremendously improved. Still had plenty of hit when I yanked on the throttle. but above 75 mph the drag started to take away acceleration (and gas mileage). I did a freeway trip where I cruised between 60 - 65 mph and averaged close to 60 mpg. Coming home late at night, I averaged about 70 - 75 mph and the mileage dropped to about 48 mpg. Wind drag really eats mileage.

Schmeck wrote: Okay After searching around Im begining to understand . Only question I really need to know now though is if Im running a 630 chain and 32 tooh rear sprocket , whats the most teeth I can put on the front ?

I recall somebody did put an 18T on the front with the 38 rear, but had to remove the front chain guard which I would think is dangerous. Could not swear to it, but I recall seeing it on the other KZ twin forum. It's really too bad that they didn't leave a bit more room for a bigger front sprocket, because I think 18/38 would be close to perfect for what I would want. But with stock guard in place, 17T is max front.

The other trick to use to get ratio down is run a larger rear tire. Mine came stock with 4.00-18 and I had run as big as about 4.65-18. In metrics, the closest to 4.00 is about 110-90-18 (?) which I run now, next time I think I will go up to a 120. Of course running a fatter tire than th rim was designed for means you burn off the center strip faster and get less miles from the tire.

I will be riding mostly highway and some back roads here and there . Im just trying to push the acceleration down alittle bit as well as the rpms' . Im running a custom exhaust with Harley mufflers ( no baffles) so there is this perfect sound right towards the bottom to mid of each gear . Im running alittle bit higher than I want at 60-65mph so Im hoping the 32 tooth will bring it down . My rear sprocket was not too expensive maybe 30 bucks . Im going to take the front guard off and see if I cant extend it to accomodate the 18 tooth . Also if there is too much slack even after pulling wheel back , I have chain rollers leftover from a suzuki rm250 that I can weld into place . Rollers look about same size as chain . I would imagine going any higher than 18 on front would cause chain problems right ? Btw I already have a 130 rear tire . Its actually smaller than what came with the bike . Only reason for changing is because the center was completely flat to hexagon . It made turns very weird . I like what im running now , extremely smooth.

Schmeck wrote: I will be riding mostly highway and some back roads here and there . Im just trying to push the acceleration down alittle bit as well as the rpms' . Im running a custom exhaust with Harley mufflers ( no baffles) so there is this perfect sound right towards the bottom to mid of each gear . Im running alittle bit higher than I want at 60-65mph so Im hoping the 32 tooth will bring it down . My rear sprocket was not too expensive maybe 30 bucks . Im going to take the front guard off and see if I cant extend it to accomodate the 18 tooth . Also if there is too much slack even after pulling wheel back , I have chain rollers leftover from a suzuki rm250 that I can weld into place . Rollers look about same size as chain . I would imagine going any higher than 18 on front would cause chain problems right ? Btw I already have a 130 rear tire . Its actually smaller than what came with the bike . Only reason for changing is because the center was completely flat to hexagon . It made turns very weird . I like what im running now , extremely smooth.

If my brain is right, I recall the stock chain was 102 links with the 16/38 set. Going down to 32 rear means you have to remove six links to fit the length. The max front gear is 18 even with the guard removed. There is a neutral indicator (?) or something else there in the vicinity.

Btw I already have a 130 rear tire . Its actually smaller than what came with the bike .

Then somebody put one giant tire on because the stock rear tire is 4.00 -18 and nowhere near that 130 size. That's about the max that will fit the swing arm?