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Now ... Measure rider-aboard "sag". There are lots of videos on the internet concerning how to do this. It requires three people ... you, to sit on your own bike, and assistant #1, to hold the bike vertical (while not adding any force up/down) while you have your feet on the pegs and hands on the bars so that your weight is fully carried by the suspension, and assistant #2, to make measurements.

In my case, which is a race bike, the rider-aboard sag is 25mm front, 25mm rear. A street set-up may want slightly more at both ends, for better ride quality.

If you have a rear shock that is too long, to some extent you can back off preload (thus leading to more rider-aboard sag) to compensate. The math for "how much" gets a little tricky, because the swingarm pivot height is dependent on both front and rear.

Make the measurements in the post above, and see where you are.
 

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Discussion Starter #22 (Edited)
To bring an update to the front ride height: 18.5mm is far too low.
I'm 6'1" (185cm) and 18.5mm makes me feel like I'm going to fall off the front of the bike; compared to stock where the front/rear was balanced.

As GoFaster mentioned, he adjusts in increments of 2mm at a time; I am actually going to double that to start and adjust front fork height (top cap above triple, since it's easier to measure this way) to 12mm (I can't maths; it would actually be 14mm). I am hoping this allows me to feel that I'm planted in the seat and not hung over the handlebars (I don't race and prefer the relaxed posture of the R3).
 

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That doesn't sound right. Do you have your handlebars above or below the triple clamp? At 18.5mm above the top of the triple clamp (not the handlebar!), if your handlebars are above the triple clamp, the top of the forks will be several millimeters BELOW the top of the handlebar, resulting in the front of the bike sitting HIGHER than stock.

Bear in mind that my forks have the Ohlins NIX22 internals and fork springs. Far from stock ...
 

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Discussion Starter #24 (Edited)
Do you have your handlebars above or below the triple clamp?
The clip-ons are above the triple clamp, setup by 75mm Woodcraft Clip-On Risers.



At 18.5mm above the top of the triple clamp (not the handlebar!), if your handlebars are above the triple clamp, the top of the forks will be several millimeters BELOW the top of the handlebar, resulting in the front of the bike sitting HIGHER than stock.
:unsure:

I've already set the Woodcraft rolling angle mechanism to favor a more horizontal alignment for the handlebars. The clip-ons now point more outward rather than downward (refer to "outward" as more in line with the "horizontal" line.



Yet it still feels like I'm tipping forward. It is possible the stock clip-ons (though they might've been lower, were actually more in line with the "horizontal" line.

Perhaps that feeling are the handlebars engineered further in (toward the tank), though I cannot position them in such a way as to clear the fairings while turning (street application; no steering stops are being used).

Also to note: it seems like the handling is much more sensitive with the way it's currently set up.



What you're saying, @GoFaster, is that the bike might actually be on rearward rake rather than a forward rake? It just feels strange - as if in fact the rear still has greater height than the front of the bike.

I am going to adjust the fork height to 14mm above the triple tomorrow and go for a test ride to see how different it is.
 

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What's the situation with the rear shock? Stock - or something aftermarket that's meant for this bike - or a longer aftermarket shock (e.g. the Ninja 650 shock that is in the title of this thread)?
 

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Discussion Starter #26 (Edited)
What's the situation with the rear shock? Stock - or something aftermarket that's meant for this bike - or a longer aftermarket shock (e.g. the Ninja 650 shock that is in the title of this thread)?
I do have the Ninja 650 rear shock installed; it raised the rear by close to 1-inch and it's on preload 1 of 7.
I'm focused on balancing that increased rear height with the front end.

I set fork height to 14mm (including top cap above triple) today; sitting on the bike feels more balanced.
It feels like I have a dashboard instead of feeling like I'm hanging over the front wheel.

I'm not so sure why such minute changes feel substantially different.
After I ride it, I will report back on how 14mm feels as far as handling (mainly turn-in sensitivity) & posture.

It's possible the last setting was actually 18mm instead of 18.5mm, as measuring to top of fork tube (as I was advised to do) is generally more difficult than measuring to fork cap top. So if you're measuring by excluding the fork tube cap, subtract 0.5mm and set torque your bolts.
 

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The longer shock is why you need to raise the front end more than I do. You need to do that in order to preserve the geometry of the front end (rake, trail). You've already got the shock set on minimum preload to try to compensate (the geometry that matters most, is the geometry that is in effect with you sitting on the bike).

You are finding out why racers make adjustments a very small amount at a time to anything that affects the geometry of the bike - ride heights, rider-aboard sag. At a certain point you do indeed to switch from what ought to be good in theory, to what feels best when you are riding it.

Your "overall higher" configuration (front and rear), once you have the front raised to match the rear, will have the following knock-on effects:
  • The swing-arm pivot will be higher leading to the swing-arm down-angle being greater because the whole bike is sitting higher. This leads to more anti-squat when accelerating and notably upon corner exit. But, given that the stock geometry has the swing-arm pivot rather low, raising it up within reason is probably a good thing rather than a bad thing. I have my Ohlins shock at the maximum ride height that Ohlins allows, and if I could get 5mm more, I would.
  • The center-of-gravity location will be higher. This will make wheelies and stoppies easier. It will limit maximum forward acceleration because it will reach the limit imposed by the front wheel coming off the ground sooner. But ... this is a 40 hp bike. It's hardly of concern and won't be a problem. It will also to some extent limit maximum available braking before the rear wheel comes off the ground. Because the forks have a rake angle, the front wheel actually goes forward a little as you raise the bike on its suspension, so this actually doesn't have a one-for-one effect. Not a big problem.
  • Your seat will be higher. If you're short, you might be on tippy-toes. This is actually the first "potentially bad" side effect ... and whether it actually is a bad thing or not ... depends on how long your legs are. If you can still reach the ground? It's not a problem!
  • Your side-stand might let the bike tilt over more ... and it's probably enough to make a quite noticeable difference. This is the second "potentially bad" side effect if you park the bike on soft surfaces or on hot asphalt. I've seen people make up a bigger foot for the side stand to spread out the load more ...
 

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Discussion Starter #28
Thank you for putting in the time to write clear & cohesive thoughts, @GoFaster.
It sounds like what you're saying is real - I feel the information is good.

I think the community would agree; you deserve this: 🏆.
 

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Discussion Starter #29 (Edited)
Rider comfort, skill, and experience
...You are finding out why racers make adjustments a very small amount at a time to anything that affects the geometry of the bike - ride heights, rider-aboard sag. At a certain point you do indeed to switch from what ought to be good in theory, to what feels best when you are riding it...
This. After all the things I've learned about ride height; it's going to work when I find what I'm comfortable with. I do remember that stock was nimble, but it wasn't eager to turn-in. Also, finding that level of comfort is highly dependent on the fact that I'm about 185lbs fully geared (83kg) and I'm 6'1" (185cm). This means my CoG (Center of Gravity) is further forward and puts more downward-force on the suspension (and affects a plethora of other forces.

What I'm comfortable with is also dependent on my skill & experience with this motorcycle (which is also not a constant - skill comes with practice and experience; consistency).

config.ini
Before I rode with the changes my 2016 YZF-R3 had:
  • 0.65kg/mm fork springs (stock)
    • with old fork fluid (12,000mi, never changed)
  • stock rear shock
  • stock clip-ons (above triple clamp)
The next thing that was done was:
  • Installed 75mm Woodcraft Clip-On Risers
    • with the clip-ons attached below the triple clamp
  • Fork ride height set to ~18mm (above triple clamp)
  • 0.80kg/mm fork springs
    • with 15W Maxima High Performance Fork Oil, and
    • fork oil set to 110mm below top of fork tube
  • A 2016 Ninja 650 rear shock at preload 1 of 7
    • came from a Ninja 650 bike that had 1,805mi
And now I've set:
  • Front fork height to 14mm
    • the measurement starts from the top of the triple clamp,
    • to the top side of the fork cap (excluding the hex bolt head)
    • this could be the sweet spot (been too busy to ride, so I can't say for sure)

Anti-squat
Your "overall higher" configuration (front and rear), once you have the front raised to match the rear, will have the following knock-on effects:
  • The swing-arm pivot will be higher leading to the swing-arm down-angle being greater because the whole bike is sitting higher. This leads to more anti-squat when accelerating and notably upon corner exit. But, given that the stock geometry has the swing-arm pivot rather low, raising it up within reason is probably a good thing rather than a bad thing. I have my Ohlins shock at the maximum ride height that Ohlins allows, and if I could get 5mm more, I would.
I will have to re-check my chain tension, as well. Because (correct me if I'm wrong) by raising the swing-arm pivot will cause the chain to loosen.
I love the fact that you brought up the term "anti-squat"; I've never learnt about it 'til now and found a 20-minute read on the subject (regarding mountain biking).

Pushing limits
  • The center-of-gravity location will be higher. This will make wheelies and stoppies easier. It will limit maximum forward acceleration because it will reach the limit imposed by the front wheel coming off the ground sooner...It will also to some extent limit maximum available braking before the rear wheel comes off the ground. Because the forks have a rake angle, the front wheel actually goes forward a little as you raise the bike on its suspension, so this actually doesn't have a one-for-one effect. Not a big problem.
Not a big problem indeed, in particular for street riders (me), who won't be testing the geometries for maximums of anything! It makes sense though: raise a bike and it decreases the wheelbase; lower it and it increases the wheelbase. Of course, there are always more factors to consider when getting into the science of suspension changes (as I learned by reading about anti-squat in the 20-minute read on the subject.

Seat height
  • Your seat will be higher. If you're short, you might be on tippy-toes. This is actually the first "potentially bad" side effect ... and whether it actually is a bad thing or not ... depends on how long your legs are. If you can still reach the ground? It's not a problem!
This; again. This is the most major downside to replacing the stock rear shock with a Ninja 650 one; it will force you to raise the whole motorcycle to make up for the increased rear ride height. This is a major downside to shorter riders. However, there are other ways shorter riders can get over the fear of being tippy-toed:
  • Safety courses
  • Slow-speed manuever practice (on a regular, bi-weekly basis)
  • Proper riding boots (will add some sole to your step)
  • Low-cut seat (like the GP-V1 low-cut)
  • Just buy a rear shock with a similar height to stock
Get tilt, son!
  • Your side-stand might let the bike tilt over more ... and it's probably enough to make a quite noticeable difference. This is the second "potentially bad" side effect if you park the bike on soft surfaces or on hot asphalt. I've seen people make up a bigger foot for the side stand to spread out the load more ...
This is an important note; I already noticed how much farther the bike leans. At first it's legitimately concerning (especially for people of less strength), because the farther it leans, means the more work it will take to get set it upright.
 

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Discussion Starter #30 (Edited)
None of this stuff really makes sense to me, but hopefully this will aid someone else who is attacking a similar problem.

Oddly enough, 14mm feels too high; that "I have a dashboard" feels more like "I'm on a chopper" (whereas 18.5mm felt like "I'm hanging over my front wheel"). I am going to lower the front end by 2mm for a total (above triple) to 16mm.

It feels as though my arms are extended farther than they should be for cruising & handling. This goes along with the sensation I've had (but haven't mentioned) in regard to my clip-ons resembling the grip of a dirtbike (straight bars outward).

Rotating them toward the tank may limit my ability to perform a full-lock U-turn, but that's how it was with stock setup. And as @GoFaster mentioned, currently my clip-ons are (supposedly) higher than stock, I should have enough clearance to make these adjustments without any negative side effects.
 

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If your clip-ons are below the upper triple clamp, they're lower than stock.

Go sit on an R1 and then come back and tell us about riding position. And ... there's a reason the R1 has them like that ... The clip-ons on my race R3 are as low as I can get them and that's with steering stops installed ...

The important thing with chassis geometry isn't what your gut-feel tells you about the riding position. It's the way the steering responds to inputs - on initial turn-in, mid-corner when feeling for grip, in response to bumps and dips, etc ...
 

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Discussion Starter #32
So instead of adjusting based on how I feel about it, I should put it through a real test; mountain roads!

I suppose I'm trying to make it feel less like a sportbike and more like a hypernaked! Maybe I should stop modding it and just ride...
 

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I ran across this today:

Visually, I'd say the distance he has the forks projecting above the top triple clamp is in the same ballpark as what I have, and we're using the same rear shock. Our forks have different internals - I'm using the Ohlins cartridges, he's using massaged stock parts - but the geometry (in terms of ride height etc) ought to be similar. Proper set-up should have the rider-aboard sag and ride height in the same range regardless of whose name is on the parts.
 

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Discussion Starter #34
I ran across this today:

Visually, I'd say the distance he has the forks projecting above the top triple clamp is in the same ballpark as what I have, and we're using the same rear shock. Our forks have different internals - I'm using the Ohlins cartridges, he's using massaged stock parts - but the geometry (in terms of ride height etc) ought to be similar. Proper set-up should have the rider-aboard sag and ride height in the same range regardless of whose name is on the parts.
I've since ridden the R3 enough to feel comfortable with the 75mm risers and ~14mm above the triple. It retains a sensitive turn-in feel, but is still nimble left to right. Overall, I think I done well enough for the cheapest suspension upgrade known to the R3 using the Woodcraft 75mm Riser Clip-ons with angle adjustments, 0.80kg/mm fork springs, stock valve bodies, and a Ninja 650 rear shock + Norton-Motorsports adapter kit.

I don't have any kind of adjustments aside from the rear shock preload (which is set to 1 of 7), but because I've only got what it is compared to stock, I'd say it's a much nicer ride for a heavier rider.

I'm not racing the R3; I just needed it not to dive so much whilst braking and I didn't realize how soft the stock rear shock was until I rode with the Ninja 650 on the street; it's a little rough, accidentally running over pot holes, but in the end is all-around the best, cheapest upgrade.

Because I ride on the street, I will never reach the limitations of the suspension; it's operational and works well for the necessary expenses.
 
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