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Junkie

Ride height

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I just picked up an FJ09 with AK20s and a Penske 8983. 

Where's the right place to run ride height? I usually run things pretty tall (I'm 6'2"), but could use some fork height and shock length suggestions. 

 

The AK20s have extended caps that allow something like an inch of extra height, and the 8983 is length adjustable, so I'm talking about ride height rather than simply preload.

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1 hour ago, Junkie said:

I just picked up an FJ09 with AK20s and a Penske 8983. 

Where's the right place to run ride height? I usually run things pretty tall (I'm 6'2"), but could use some fork height and shock length suggestions. 

 

The AK20s have extended caps that allow something like an inch of extra height, and the 8983 is length adjustable, so I'm talking about ride height rather than simply preload.

Congratulations on the new bike, especially with Traxxion Dynamics goodies.  👍

Ride height adjustments are to change the bikes steering geometry NOT to adjust for a short or tall rider, a 5' and 6' tall rider could potentially use the same ride height settings, I believe the shocks ride height adjustment is only 12mm fully extended.  My suggestion would be to go to a suspension tuner and have them do a baseline setup for you.

Slide4.jpg

Ride height adjustment is a feature you can find on high range & top line...

 


***2015 Candy Red FJ-09***

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I'm aware that it's to get the bike geometry correct, but in many cases a shorter rider will make compromises so that they can easily ride the bike. I was stating height just to make it clear that I don't need to make any of those compromises. 

 

I have an appointment with a suspension tuner tomorrow, but that doesn't mean that he knows all of the right geometry tweaks on an FJ09. 

 

12mm is the shock length adjustment, ride height change is almost certainly a few times that. I measured fork cap extension length and it's around .85"/22mm and I imagine rear ride height would change significantly more than that from a 12mm shock length change - hell, if my shock is set dead center (don't know if it is), I imagine I could probably raise it that much.

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I wouldn't mess with the geometry on my bike. If I could, I guess I would be a suspension guy or work for Yamaha. I think at least a few minutes goes into the development of the suspension of our bikes by the Yamaha people.

Don't mean to sound snarky, but I would imagine a lot of math is involved. I'm not smart enough to design my own bike.

I had my suspension adjusted by Dave Moss one day at Cycle Gear. He said he moved his forks up or down a few mm, I'm not sure, but I think it's a feel thing. Said it turned in quicker.

I've seen lowering links, and not sure if that changes the stock geometry for better, worse or no change?

For tall guys? Maybe seat height, lower pegs?

 

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I'd be surprised if Dave Moss was moving the forks in the clamps in a Cycle Gear suspension adjustment but I suppose it's possible. 

In general, raising the rear or lowering the front will make the bike turn in quicker and put more weight on the front wheel, at the expense of stability. Raising or lowering the entire bike a fixed amount mostly impacts anti-squat geometry, a higher bike will squat less on the gas and therefore be less inclined to run wide, but at the expense of some rear tire traction. 

 

I'm not new to riding or suspension (I race supermoto, obviously different bikes), but different bikes want different changes and I figured asking is easier than making the adjustments and testing myself.

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17 hours ago, Junkie said:

I'd be surprised if Dave Moss was moving the forks in the clamps in a Cycle Gear suspension adjustment but I suppose it's possible. 

In general, raising the rear or lowering the front will make the bike turn in quicker and put more weight on the front wheel, at the expense of stability. Raising or lowering the entire bike a fixed amount mostly impacts anti-squat geometry, a higher bike will squat less on the gas and therefore be less inclined to run wide, but at the expense of some rear tire traction. 

 

I'm not new to riding or suspension (I race supermoto, obviously different bikes), but different bikes want different changes and I figured asking is easier than making the adjustments and testing myself.

I wasn't too clear. Dave said he owns a Tracer (maybe he said MT or FZ, not sure) and moved the forks in the clamps. Said he wanted the bike to turn in quicker.

At Cycle Gear I received the the normal adjustment you receive for $40.00 which included questions on style of riding, sag adjustment then test ride and adjust again if necessary.. He was pretty thorough. Adjustment/Test Ride three times. He had a steady flow of bikes to adjust all day. 

I watched him adjust three Ducatis. Not sure what was up (I didn't ask), but he took a hammer to the shock on all three. Shock adjustment on those were intense. 

The forum is very informative. Someone will probably respond with a more helpful response than I gave you. 

 

 

Edited by fr8dog
add info

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On 2/6/2021 at 10:12 AM, fr8dog said:

I wasn't too clear. Dave said he owns a Tracer (maybe he said MT or FZ, not sure) and moved the forks in the clamps. Said he wanted the bike to turn in quicker.

At Cycle Gear I received the the normal adjustment you receive for $40.00 which included questions on style of riding, sag adjustment then test ride and adjust again if necessary.. He was pretty thorough. Adjustment/Test Ride three times. He had a steady flow of bikes to adjust all day. 

I watched him adjust three Ducatis. Not sure what was up (I didn't ask), but he took a hammer to the shock on all three. Shock adjustment on those were intense. 

The forum is very informative. Someone will probably respond with a more helpful response than I gave you. 

 

 

sometimes the only way to get the preload ring to turn is with a hammer and punch. 

since I have a length adjustable shock, I'm more inclined to raise the rear than lower the front

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I agree though the FJ/Tracer has enough travel to raise the tubes up to 6 mm on my fastest red 15. I tried it and then went back down but only after getting spring rate set (.95 straight rate Sonics as I'm 240 in full gear and 6' - 1), a 155 mm air gap with 16 cSt @ 40C fork fluid dialed-in in conjunction with massaged OEM rebound and compression damping in BOTH legs balanced to my custom set K-Tech Razor-R with length set  at + 4 mm OEM, which equates to about +12 mm in ride height.  That is a lot given the linkage ratio and more of an effect than - 6 mm up front.  I have not felt any instability as a result even with the 2 inch shorter swing arm than what came online with what, the 18s?  BTW, going up much more in the rear and it gets tippy on the side stand.  Tires and tire pressure come into play here along with back-torque control (I installed a 16 XSR slip/assist clutch), ECU flash, brake upgrades, saddle and foot peg heights, riding style, what you had for breakfast and side of the bed you sleep on, etc...

But as a SM racer, you know all this... 😎

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I know the basics of how it works, but different bikes are set up differently from the factory and it's nice to have input from someone about how this specific bike is configured. 

 

Having taken it on a decent ride Saturday, I'd certainly like to make the geometry a little more aggressive. I need to talk to Traxxion and confirm that the shock is set up to have a range from -6mm to +6mm, if that's the case I believe mine might be set just a little bit under stock length. 

 

I'm considering raising the front of the bike about 10mm (pushing the forks down in the triples), and raising the rear of the bike about 15mm (based on your number, shock approximately +5mm) to see how it does. 

 

I have a decent welding setup and am not awful at it, so I can make and attach an end plate for the sidestand and center stand if needed.

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I would just temporarily as a starting point RAISE the tubes about 6 mm, no more than 8, add a bit of preload, increase rebound and compression 4 clicks, and add a bit of shock preload but soften compression but increase rebound slightly.  Then give it a door go in the fast and tight stuff but consider hiway and in-town comfort.  Lengthening the shock entails removing at least the linkage, so if you have over 24k miles, it'd be a good time to clean and lube the swing arm and linkage bearings and shock bearing & bushing...

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6 minutes ago, 2and3cylinders said:

I would just temporarily as a starting point RAISE the tubes about 6 mm, no more than 8, add a bit of preload, increase rebound and compression 4 clicks, and add a bit of shock preload but soften compression but increase rebound slightly.  Then give it a door go in the fast and tight stuff but consider hiway and in-town comfort.  Lengthening the shock entails removing at least the linkage, so if you have over 24k miles, it'd be a good time to clean and lube the swing arm and linkage bearings and shock bearing & bushing...

Lengthening a length adjustable Penske or Ohlins is very easy: you loosen the jam nut (silver in my picture) and thread the length adjustment nut (black) away from the clevis, which lengthens the shock. Then, tighten the jam nut. I'd say it's easier than adjusting fork height as long as you have the right size wrench (on a Penske I believe it's 1"). Adjusting fork height requires touching 6 fasteners at least 2 times each, rather than touching one fastener once and another twice. 

eDNPyLhb5ACTAroGXPUvCay9cchIMU48YXg3vf4MUirHgv2Es2jZ6zhSB7yZQFJ4S8Zjw1fO1X-YCirJLt5m-2OiuIYAJehKAp2CJBeA54gI0ObNzcCfqDPGG0o0YnjrzvwcOivde-RfKsEeIWorPzqr5npgjz6VijT-1a9spIMSOnT_u4svUyQzG4brJvPlCpq0y7SSg5pRHGRuWYEz7zsBrIv16ycSNRL3LhBUxye-0cDXpbg9ak9He5qoIn9W2oH2sgBNrCuRUNOWbn2HMV_wtVRE33FLdaocTe1_uj1wU_ux161eI9AGQvhYF_2GM9ll56cQpr6LLt8ABlHhkEYQh_MUmdoGf0-lIaqTdx0LohVLhtcFvKGwRn_OIBh6o48PXK9TF-9aBuXt2C-Ti1xkgutvpYr-U4pBOaF7HytfAyi5wI5tTz_bfIr2-uks8v5Ha18ppcNZxVBG0n64gou4-JoD_zcb5Y6BLhx6plLOf6PglXJ3xTaSaeYYMAhkPy0f_3gntaR2w6r76Qe8vhN-P48mDf5AOCG8iT0mn2BJGwpfzvYDiw4PKbVXT9ziTtDl5vIiCWf23_JyikF3z34Nv9QV8v9_JUzaRDWj75uRuCYplS6M6GmDam4GG8nJw98XIPUZmUuMq3-GErn-cLDH5Sgs3fonaL66IlHkTkFiXFovizMX7q9qCMDVfA=w469-h625-no?authuser=0

I had my suspension dialed in for me on Saturday before I rode it. Rear sag was spot on, front sag was low (so he removed some preload), damping on both ends was a little stiff (I suspect it was set up during summer, fork and shock oil are thicker when it's cold). 

 

Bike has 14k on it, so while it could probably use some chassis lubrication it isn't in dire need of it. I'll do it at some point anyway.

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On my old Penske you have to break loose the lock nut and remove the bottom clevis Bolt, turn the Clevis while holding the body Bolt as seen in the picture

Same on my newer K-Tech on my FJ

20210208_152236.jpg

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2 minutes ago, 2and3cylinders said:

On my old Penske to weigh you have to break the lock nut and remove the bottom clevis Bolt, turn the Clevis while holding the body Bolt as seen in the picture

20210208_152236.jpg

I did that on a previous bike and was then told that you can do what I'm saying. Maybe it isn't universal. 

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