Lowering my 1975 Z900
- 650ed
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Re: Lowering my 1975 Z900
28 Apr 2013 13:17
One more try:
What is the size (such as 120/90-18) of the rear tire currently on the bike? Ed
What is the size (such as 120/90-18) of the rear tire currently on the bike? Ed
1977 KZ650-C1 Original Owner - Stock (with additional invisible FIAMM horn)
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- ed spangler
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Re: Lowering my 1975 Z900
28 Apr 2013 14:47650ed wrote: One more try:
What is the size (such as 120/90-18) of the rear tire currently on the bike? Ed
Sorry Ed, :blush: :ohmy:
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Wish bike was here I would look , unfortunately its at my friends shop and he's gone .
Does "Stock Size" help..??
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Have 1975 Kawasaki Z1-B & 2003 Harley Davidson Heritage Softail Classic
Had Hondas, Harleys and many ,many Z Series Kaws both Std. & LTD's
Had Hondas, Harleys and many ,many Z Series Kaws both Std. & LTD's
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- ed spangler
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Re: Lowering my 1975 Z900
28 Apr 2013 14:56
Nope,
not gonna toss current rear shocks, they are new, only been on the bike since 2011, maybe 5000 miles total on them. Think I got them from the KZ supplier out in California.used to be highway 66 Kawasaki ? or something like that?.?? Or... maybe Z1E, cant recall now.
Ya know , I used to work in the Auto parts business ED, and we always had reference books that showed diameter, compressed length, each end mounting type etc. etc. so if we had a customer come in with a shock off an old vehicle that we had no "Official Listing" for, we would simply measure the shock identify each ends mounting type ( Eye opening size, Stud etc. ) compressed length etc. etc. compare it to our book and "voila", we had a close match that almost always would work. Granted , we could not guarantee no interference but we always told folks to check that. wonder if there's such a thing as a reference book for Motorcycle shock supplier?? Thanks for all your help ed!
TennesseeZ ED
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Ya know , I used to work in the Auto parts business ED, and we always had reference books that showed diameter, compressed length, each end mounting type etc. etc. so if we had a customer come in with a shock off an old vehicle that we had no "Official Listing" for, we would simply measure the shock identify each ends mounting type ( Eye opening size, Stud etc. ) compressed length etc. etc. compare it to our book and "voila", we had a close match that almost always would work. Granted , we could not guarantee no interference but we always told folks to check that. wonder if there's such a thing as a reference book for Motorcycle shock supplier?? Thanks for all your help ed!
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TennesseeZ ED
Have 1975 Kawasaki Z1-B & 2003 Harley Davidson Heritage Softail Classic
Had Hondas, Harleys and many ,many Z Series Kaws both Std. & LTD's
Had Hondas, Harleys and many ,many Z Series Kaws both Std. & LTD's
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- 650ed
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Re: Lowering my 1975 Z900
28 Apr 2013 16:10
Most older, inch-designated tires had sidewall heights approximately equal to their section width, so an original 4.00 inch wide tire would also have a sidewall height of approximately 4.00”.
The aspect ratio on metric tires can be used to calculate their approximate height by multiplying it times their width. The height of a 120 width tire (which I believe is the best metric replacement for a 4.00 inch designated tire) varies depending on the aspect ratio. So a 120 x 90 x 18 tire = approx. 108mm (4.25”) sidewall height and a 120 x 80 x 18 tire = approx. 96mm (3.78”) sidewall height.
Given that, if you switched the 120 x 90 x 18 rear tire for a 120 x 80 x 18 tire the rear of the bike would be approximately ½” lower without moving the tire any closer to the fender. I know ½” is not a lot, but if it was done in addition to the other changes you are contemplating it might help. Maybe consider it for your next tire change.
Regarding the shocks, you may want to contact Dave Quinn at davequinnmotorcycles.com . He sets up and sells Hagon shocks and is extremely knowledgeable about shock lengths, spring weights, etc. I bought shocks from him about 6 years ago and he was very easy to talk to and seemed happy to share information. So even if you don’t plan on buying Hagon shocks it might be worthwhile to call him to pick his brain. BTW, I love my Hagon shocks; they replaced my S&W shocks and they work every bit as well and they are stainless steel. Regards, Ed
The aspect ratio on metric tires can be used to calculate their approximate height by multiplying it times their width. The height of a 120 width tire (which I believe is the best metric replacement for a 4.00 inch designated tire) varies depending on the aspect ratio. So a 120 x 90 x 18 tire = approx. 108mm (4.25”) sidewall height and a 120 x 80 x 18 tire = approx. 96mm (3.78”) sidewall height.
Given that, if you switched the 120 x 90 x 18 rear tire for a 120 x 80 x 18 tire the rear of the bike would be approximately ½” lower without moving the tire any closer to the fender. I know ½” is not a lot, but if it was done in addition to the other changes you are contemplating it might help. Maybe consider it for your next tire change.
Regarding the shocks, you may want to contact Dave Quinn at davequinnmotorcycles.com . He sets up and sells Hagon shocks and is extremely knowledgeable about shock lengths, spring weights, etc. I bought shocks from him about 6 years ago and he was very easy to talk to and seemed happy to share information. So even if you don’t plan on buying Hagon shocks it might be worthwhile to call him to pick his brain. BTW, I love my Hagon shocks; they replaced my S&W shocks and they work every bit as well and they are stainless steel. Regards, Ed
1977 KZ650-C1 Original Owner - Stock (with additional invisible FIAMM horn)
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- ed spangler
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Re: Lowering my 1975 Z900
29 Apr 2013 07:15650ed wrote: Most older, inch-designated tires had sidewall heights approximately equal to their section width, so an original 4.00 inch wide tire would also have a sidewall height of approximately 4.00”.
The aspect ratio on metric tires can be used to calculate their approximate height by multiplying it times their width. The height of a 120 width tire (which I believe is the best metric replacement for a 4.00 inch designated tire) varies depending on the aspect ratio. So a 120 x 90 x 18 tire = approx. 108mm (4.25”) sidewall height and a 120 x 80 x 18 tire = approx. 96mm (3.78”) sidewall height.
Given that, if you switched the 120 x 90 x 18 rear tire for a 120 x 80 x 18 tire the rear of the bike would be approximately ½” lower without moving the tire any closer to the fender. I know ½” is not a lot, but if it was done in addition to the other changes you are contemplating it might help. Maybe consider it for your next tire change.
Regarding the shocks, you may want to contact Dave Quinn at davequinnmotorcycles.com . He sets up and sells Hagon shocks and is extremely knowledgeable about shock lengths, spring weights, etc. I bought shocks from him about 6 years ago and he was very easy to talk to and seemed happy to share information. So even if you don’t plan on buying Hagon shocks it might be worthwhile to call him to pick his brain. BTW, I love my Hagon shocks; they replaced my S&W shocks and they work every bit as well and they are stainless steel. Regards, Ed
Thanks Ed
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Interesting idea about going to an 120x80x18 rear tire :woohoo: ,that combined with a slightly shorter rear shock would be a good inexpensive compromise!! OR , Someone had also suggessted checking JC Whitney for a rear shock lowering kit, I did that ( Original cost just $15.00!!) and it is on their website, however its discontinued.
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Thanks Again
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TennesseeZ aka ED
Have 1975 Kawasaki Z1-B & 2003 Harley Davidson Heritage Softail Classic
Had Hondas, Harleys and many ,many Z Series Kaws both Std. & LTD's
Had Hondas, Harleys and many ,many Z Series Kaws both Std. & LTD's
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- peter1958
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Re: Lowering my 1975 Z900
29 Apr 2013 08:15
They come up on ebay . That would be the way to go.
www.kzzone.com/
cavanaughracing.com/kzdata.html
www.mtceng.com/index.php/us-dealers/44-f...-performance-orlando
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- Mcdroid
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Re: Lowering my 1975 Z900
29 Apr 2013 08:18
Hey ED...I suspect that making any permanent changes to your shock mount position on your Z-1B using a welder is ill-advised.
Michael
Victoria, Texas
1982 GPz750
1977 KZ1000A
1978 KZ1000A
1982 GPz1100
1975 Z2A
Victoria, Texas
1982 GPz750
1977 KZ1000A
1978 KZ1000A
1982 GPz1100
1975 Z2A
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- Roguedog69
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Re: Lowering my 1975 Z900
02 Jun 2013 08:20
Hello All,
Roguedog here, first posting. Great Forum by the looks.
These range of shocks might help in lowering. Good Luck.
www.gazisuspension.com/products.html
Roguedog here, first posting. Great Forum by the looks.
These range of shocks might help in lowering. Good Luck.
www.gazisuspension.com/products.html
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