rear sprocket swapping

will a rear sprocket from a 77 kz1000 fit a 76 kz900? i would like to drop down 2 teeth in the back of my 900 but the only sprocket i have been able to find so far with 33 teeth is for the 1977 kz1000a. my stock sprocket is 35 teeth and is worn out. (and geared too loww for me) thanks. i would do the 530 conversion but i still have 2 new 630 chains left i have to use first...:laugh:

p.s. will this require a shorter chain as well?

Post edited by: arobsum, at: 2007/08/26 10:36

Hi Arobsum,

If your rear sprocket is worn so is your front sprocket. They should always be replaced as a pair.

A set of sprockets from a 76 LTD will fit and lower the ratio as well.

KZCSI

KZCSI wrote:

Hi Arobsum,

If your rear sprocket is worn so is your front sprocket. They should always be replaced as a pair.

A set of sprockets from a 76 LTD will fit and lower the ratio as well.

KZCSI

1976 kz900 LTD. got it. thanks! how about the chain? will i have to shorten it? i added the chain bit in there after you had responded. i just thought of it.:whistle:

well, i just went to denniskirk.com and it shows the LTD rear sprocket the same as the standard. is it the front sprocket that has more/less teeth?

Hi Arobsum,

Sorry my mistake, I knew that the LTD's had lower gearing. I suppose it might be because of the smaller rear wheel. Now I'm not even sure of that, according to KZR the LTD and the standard KZ900 had the same gearing and wheel sizes.

My KZ900 shop manual refers to a 33 tooth sprocket for a European model.

KZCSI

Post edited by: KZCSI, at: 2007/08/26 12:00

FSM for KZ900LTD USA model shows:

Gear ratio:
1st 3.17 (38/12)
2nd 2.19 (35/16)
3rd 1.67 (35/21)
4th 1.38 (29/21)
5th 1.22 (28/23)

Primary reduction ratio: 1.73 (97/56)

Final reduction ratio: 2.33 (35/15)

Overall drive ratio: 4.92 (5th)



If interpreting correctly, the Final reduction ratio figures "(35/15)" refer to a 35 tooth rear sprocket and a 15 tooth front sprocket.

Post edited by: Patton, at: 2007/08/26 12:02

And those are the same numbers from the FSM for the KZ900. I had thought that the LTD's had lower gearing.

KZCSI

Patton wrote:

FSM for KZ900LTD USA model shows:

Gear ratio:
1st 3.17 (38/12)
2nd 2.19 (35/16)
3rd 1.67 (35/21)
4th 1.38 (29/21)
5th 1.22 (28/23)

Primary reduction ratio: 1.73 (97/56)

Final reduction ratio: 2.33 (35/15)

Overall drive ratio: 4.92 (5th)



If interpreting correctly, the Final reduction ratio figures "(35/15)" refer to a 35 tooth rear sprocket and a 15 tooth front sprocket. <br><br>Post edited by: Patton, at: 2007/08/26 12:02

The FSM KZ900 also shows these differences between the US and European models


Final reduction ratio:
US 2.33 (35/15)
European 2.20 (33/15)

Overall drive ratio:
US 4.92 (5th)
European 4.64 (5th)

Thought there might be a difference in the overall rear tire diameter between the 18 inch KZ900 and 16 inch LTD models, as the possibility of a smaller overall rear tire diameter on the LTD could explain slightly lower final gearing on the LTD.


Well this theory failed, as rough measure with steel tape shows both rear tires at approx 26 inches overall diameter. :ohmy:


73Z1 with Bridgestone 110/90H18 (Bridgestone's replacement for 73Z1's OEM 4.00H-18)

76KZ900LTD with Dunlop 491 Elite II MT90B16 (Dunlop's replacement for KZ900LTD's OEM Goodyear Eagle MT90-16).

From File Base (Exhaustive Development History of Z1)

1976 KZ900

CHAIN AND SPROCKETS:

FOR THE FIRST TIME AN ALTERNATIVE REAR SPROCKET WAS OFFERED FOR THE 900 RANGE. THE A4 WAS FITTED WITH A 33 TOOTH ITEM AS STANDARD IN THE UK AND MANY OTHER MARKETS WITH ONLY ITALY KEEPING THE PREVIOUS 35 TOOTH SPROCKET.

NEW PART NUMBER:
SPROCKET: 42041-161 33 TEETH

Patton wrote:

From File Base (Exhaustive Development History of Z1)

1976 KZ900

CHAIN AND SPROCKETS:

FOR THE FIRST TIME AN ALTERNATIVE REAR SPROCKET WAS OFFERED FOR THE 900 RANGE. THE A4 WAS FITTED WITH A 33 TOOTH ITEM AS STANDARD IN THE UK AND MANY OTHER MARKETS WITH ONLY ITALY KEEPING THE PREVIOUS 35 TOOTH SPROCKET.

NEW PART NUMBER:
SPROCKET: 42041-161 33 TEETH

cool. just what i am looking for. i wonder if kawasaki.com shows it? i will find out!