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Discussion Starter · #1 · (Edited)
I ordered some ebay aluminum dogbones that are marketed as "lowering links" for the ninja 400. They have two holes in the dog bones, so I thought maybe they could raise or lower the rear.

I tried them out today and found that by using the shorter of the two holes, the swingarm is dropped (rear of bike raised) by about an inch and an 8th (1.125" or about 28.5 mm).

My first attempt at determining swingarm angle may be incorrect, but I got 11.67 degrees. I am not altogether clear on what "unloaded" means for measuring the swingarm angle.

The weight of the two stock dogbones totals 300 grams. The weight of the alloy ones totals 170 grams, so a saving of about 130 grams.

Attached is a picture of the units I purchased. Cost was under $35.00 including shipping. I haven't had a chance to test ride yet but will report back once I do.


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Unloaded means the rear wheel is up in the air, not touching the ground. I've never got a clear answer in the past on what the correct way is to measure the swing arm angle, but I believe you can do it with the bike upright and on the ground. No extra load on it, just it's own weight. However when making modifications like this, the important thing is that you take the measurements the same way to remove all variables. With these dogbone links being advertised as lowering links, I have a bit of a hard time believing you were able to raise the rear. Usually the ones I've seen that look like this have 2 holes because you can choose 2 levels of lowering, but both are lower than stock. Or one is stock and the other one is lower. And if it did raise it, then 28.5mm is HUGE!!
 

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Discussion Starter · #4 ·
@sbk1198 - My notebook with traced images of stock and replacement dogbone. Sizes noted on drawing...

Apologies for the crude drawing and notes. Wasn't expecting to share!

Rough measurements, center of hole to center of hole:
Stock: 167mm
Alloy hole 1: 177 mm
Alloy hole 2: 159 mm

These do indeed provide both lowering and raising options.

So to raise the rear, use hole 2. Difference between stock and hole 2 is 8 mm. Which resulted in approximately 1.125" (28.5mm) higher in the rear.

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@sbk1198 - My notebook with traced images of stock and replacement dogbone. Sizes noted on drawing...

Apologies for the crude drawing and notes. Wasn't expecting to share!

Rough measurements, center of hole to center of hole:
Stock: 167mm
Alloy hole 1: 177 mm
Alloy hole 2: 159 mm

These do indeed provide both lowering and raising options.

So to raise the rear, use hole 2. Difference between stock and hole 2 is 8 mm. Which resulted in approximately 1.125" (28.5mm) higher in the rear.
Ahh I see. Nice that they did it like that and one hole is used for lowering while the other for raising. Thanks for posting the measurements. You got a link for where you got them from? I may get myself a set too now! :)
 

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Discussion Starter · #8 ·
I got them from ebay, being sold by a seller called bijiaauto2. They shipped from China. They appear well made, but I will definitely be keeping an eye on them for the first few times I ride.

Here is a link to a current auction for a set. He also has them in green and perhaps other colors. Company name for the vendor that makes them appears to be bjmoto.

keyword search on ebay: ninja 400 bjmoto lowering links

Here is a link to a current auction for a set on ebay:

bjmoto Lowering Links Ebay Ninja 400
 

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...And if it did raise it, then 28.5mm is HUGE!!
Interesting. On the SVs 28mm would have been too little, especially on the first gens. On those we typically went from the stock 338mm to 352mm on shock length, which given the linkage ratio resulted in 35mm or so of rear ride height increase. And we also lowered the front. :)
I guess the 400 isn't as far off as the SVs were.
 
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Interesting. On the SVs 28mm would have been too little, especially on the first gens. On those we typically went from the stock 338mm to 352mm on shock length, which given the linkage ratio resulted in 35mm or so of rear ride height increase. And we also lowered the front. :)
I guess the 400 isn't as far off as the SVs were.
Where is that 35mm rear ride height measured from though? I was waiting @kpier883 to answer the above question also. On the 400 most people seem to increase the shock length by 5-10 mm...not sure what that results in as far as rear ride height change.
 

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On the 400 it’s about a 2:1 ratio. 5mm at the shock equals 10mm ride height.
I want to get myself some dog bone linkages now but I don't want such a drastic difference. kpier says 28 mm ride height difference from a 8 mm difference in linkage length. I think I'll make myself a set with something less than that and see how it goes.
 

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Where is that 35mm rear ride height measured from though? I was waiting @kpier883 to answer the above question also. On the 400 most people seem to increase the shock length by 5-10 mm...not sure what that results in as far as rear ride height change.
I always measure from the rear axle to a fixed point on the bodywork, directly on a vertical line.

The 28.5mm may or may not be correct. When I owned Sonic Springs customer-supplied sag measurements were the bane of my existence. 90% of them were obviously wrong.
 
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Discussion Starter · #15 · (Edited)
@Topaz, @sbk1198

Sorry for the delay guys. I am most appreciative of all you weighing in on this mod!

I wanted to get a picture to avoid any confusion, so I decided to wait to get home from work before answering up on the measurement questions.

It is kind of arbitrary, but this is the distance I measured - center of axle to a fairing bolt head. It might be difficult to see the little bolt head on the bodywork, but it is a consistent point. We can round to 1 inch higher on this measurement. This picture was taken with the bike on the sidestand. I think the time before when I measured, I was doing my best to hold the bike upright.



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@Topaz, @sbk1198...This picture was taken with the bike on the sidestand. I think the time before when I measured, I was doing my best to hold the bike upright...
That's were you went wrong, you can't compare a sidestand measurement (where some of the bike's weight is supported by the stand) to a measurement with all the bike's weight on the wheels.

Any kind of sag or ride height measurement needs to be done consistently, and with a helper. Solo measurements give inaccurate results.
 

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Discussion Starter · #17 ·
I tried measuring swingarm angle tonight as follows.

Font Circle Parallel Number Symmetry

My basement floor is pretty level, so the assumption is fine. Apologies for the drawing. Best I could do with MS Paint and Paint 3d.

I think my swingarm angle is right at 12 degrees. Seems like an okay value based on the "ballpark figures" I have seen of 11 to 12.5 degrees (Dave Moss) or this video from the Traxxion Dynamics People stating 12 to 13 degrees.

As always, I welcome your comments!
 
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