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Discussion Starter #1
Put a 21" wheel on my Street Glide. Need to drop'er down 1-2 inches. Anyone tell me how low I should go.
 

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How low do you want to go? I'm thinking 1-2 inches is as low as you can go with a different set of springs. If you want to go lower a new wheel would be in order.
 

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If your stock wheel is a 17" and you went to a 21" that's a 4" height difference but from center of the wheel only 2" difference. I think 2" drop would get you pretty close to stock stance.If stock was 18" that's a 3" difference so 1.5" drop but you May want to search the forum for people who have lowered their bike 2", because 2" lower is going to affect the travel in the front.
 

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Wayward Son
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If you want level do as MVious1 said. Figure out the difference in diameter of the original tire and the new 21".
Divide by half. That will give you as close as you will get to dropping it back to level.
Unless of course you have lowered the back end.
 

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If your stock wheel is a 17" and you went to a 21" that's a 4" height difference but from center of the wheel only 2" difference. I think 2" drop would get you pretty close to stock stance.If stock was 18" that's a 3" difference so 1.5" drop but you May want to search the forum for people who have lowered their bike 2", because 2" lower is going to affect the travel in the front.
But the sidewall on the 21" tire is shorter than the 17", so the tire diameter wont be a 4" difference....


For example, the 21" tire on my bike has the same diameter as the 19" on a Sportster.
 

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Agreed , that was just my simple way to help him to figure it out .I was kinda assuming Z006 would use the actual total height difference that's really the only way regardless of wheel size.
 

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120/70/21 = 27.67 diameter

130/80/17 = 25.2 diameter

Your front end should slightly more than an inch higher than stock.
 

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Wayward Son
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120/70/21 = 27.67 diameter

130/80/17 = 25.2 diameter

Your front end should slightly more than an inch higher than stock.
With that minimal of difference you may want to leave well enough alone.
It looks to be right around 1.25" of rise. I believe 1.5 drop kits are sold. A properly trimmed PVC spacer could do the trick between the 1.5 that is sold and the 1.25 you seem to need.
Look at it. Ride it a while.
You may decide to leave it as is.
If you like to launch hard the slight weight shift may help.
 

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Discussion Starter #9
Thanks people. Great help. I have ridden it & you can sure feel the height difference. It just doesn't look right. Do notice that after rounding a corner it takes more effort to straighten it out. She will be coming down. 1.5 - 1.75 should do it.
 

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Try loosening your triple tree clamps and sliding the forks up as high as they will go without hitting the handlebars. You should get about a 3/4in drop. Its free and you keep full suspension travel.
 

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Wayward Son
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Would not go more then 1.5.
Without exact measurements can not figure out the exact current drop and what is needed to bring it back to level.
But going too low in front will really mess up the geometry of the bike.
You will effectively be placing more weight on the front end. This will increase during braking when the weight is naturally shifted forward anyways.
That will cause an even heavier feeling front end. As well as an greater amount of nose dive.
 

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Discussion Starter #12
Yep. As soon as I get the springs, she's going to drop about 1 1/4. I do have a set of Monotubes with the 2 inch drop option in the for sale section.
 
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