New Sprockets

1981kz550ltd wrote:

haha, my bubble is still intact! a new chain shouldnt be too expensive cuz its not an o-ring chain. like $30.

I wouldn't risk my leg to a $30 chain.

Vter Bob wrote:

I'm not sure there is room to go any larger than 17 tooth on the front sprocket.

Yeah, life would be so much better if an 18T would fit on the front, but they don't.

bountyhunter wrote:

Vter Bob wrote:

I'm not sure there is room to go any larger than 17 tooth on the front sprocket.

Yeah, life would be so much better if an 18T would fit on the front, but they don't.

You've got a lot healthier 550 than I do if you think it would pull an 18

mjg15 wrote:

bountyhunter wrote:

Vter Bob wrote:

I'm not sure there is room to go any larger than 17 tooth on the front sprocket.

Yeah, life would be so much better if an 18T would fit on the front, but they don't.

You've got a lot healthier 550 than I do if you think it would pull an 18

Mine's a 750 twin which could easily pull an 18T front with the stock 38T rear and that would be perfect, but the diameter of an 18T won't fit at the front.

I'm not sure a 550 would be happy at the same ratios my 750 pulls.

My 550 seems to have plenty of power in 6th gear with the stock sprockets. i dont have any problem accelerating from 45mph to 60 in no time. I know i need a new rear sprocket. and a new front. if i am gonna have to get a new chain anyway. id rather take everything apart once and be done. SO what do u recomend? Just going with a 17 front. and 38 rear? or a step further. 17 front and 37 rear?? would the latter be too much??

Stock is 16/40 on the "A" model 550, not sure about the LTD. 17/38 is lot taller than the stock 16/40, I wouldnt go any further than that. I may go to a 17/40. I guess it depends on you intended usage.

the stock LTD is 16/38. the LTD was designed more for the cruiser, so they made it taller. so r u saying i should go with the 17/38 setup? im at the stock 16/38 with brand new bridgestone spitfires. and im about 3800 rpm at 45 mph. im looking to be around 4500 or so at 60. now im around 5100 at 60

1981kz550ltd wrote:

the stock LTD is 16/38. the LTD was designed more for the cruiser, so they made it taller. so r u saying i should go with the 17/38 setup? im at the stock 16/38 with brand new bridgestone spitfires. and im about 3800 rpm at 45 mph. im looking to be around 4500 or so at 60. now im around 5100 at 60

Important point: how much do you weigh and do you ride a passenger? With a bike which weighs maybe 450 pounds, rider(s) weight is a huge factor. I weigh 170 and only ride single, and I went up 15% on stock ratio (it's a 750 twin). Stock was 16/38 and I ran 16/32.

Go by percent: if you change your front from a 16T to a 17T, you will drop cruise RPM by 1/16 which is about 6.3% which is not much. If you are fairly light and don't carry a passenger, I would be surprised if you couldn't change by 10% and still have decent acceleration. However, with a heavy rider or passenger, it might not pull well.

im looking to be around 4500 or so at 60. now im around 5100 at 60

You want a change of about 600/5100 = 12%

I think you could do that with 17/36 ratio.

The LTD has a 16" rear wheel and my A model has an 18. I'm not sure what the actual difference in tire circumference is, but I would guess that the gearing change between the two models is Kawasaki's attempt at equalizing this difference in tire circumference more than it is an attempt at making the bike more of a highway cruiser. The stock A also runs 5100 @ 60, but with 16/40, so I would say that they were successful. Your LTD should be fine with a 17/37 combo, but as you expect, you will lose a considerable amount of acceleration in 6th

The difference in tire diameter between a 130/90/16 and a 120/90/18 is only 1/4" to 3/8" depending on manufacturer and model.

Seems like it would be more, don't it?

Heres some data to consider. this is a dyno chart from an '80 KZ550. Note that there is 15% less power available at 4500 compared to the amount @ 5000. I'm not sure of actual numbers, but lets assume that it takes half of the power available to mainatain 60mph, then that 15% that you remove by changing the gearing is actually more like a 30% reduction of the power available for acceleration or for maintaining speed on a grade.

speed

id rather do my accelerating in 5th. and cruise in 6th at a nice comfortable rpm thats not "buzzy" at 60 mph.