Bike tends to stand up

[Auspanglish]

Hi, don't believe I've seen this issue dealt with in a thread so...

So like the title says, I've been noticing it for some time now, wasn't really an "issue" before, but it's getting progressively worse.

The bike doesn't want to stay leant over, if I hit a bump it will stand up, not dangerously unless on cold, wet asphalt with cold, wet tyres on the slippery white paint over here in Spain. Sometimes I don't even have to hit a bump.

I have the tubes raised 5 mm in the triples. I have conical steering head bearings installed instead of the OEM ball-type ones. I have stock everything else except the fok oil which is SAE 15W. The bike (2003 VTEC) has 77000 km on it. Original springs and shock. I have tried all sorts of preload settings but to no avail. The more preload I give it, the harsher the ride and the springs just want to extend too quickly and sometimes don't even feel like they're absorbing bumps... don't know whether this is just preload or the heavier weight oil as well...

For those of you who read my latest track-day write up, don't confuse this with the same tendency to stand up due to excessively low pressure in the slicks I had fitted... I have checked my tyre pressure (Pilot Road 2CTs with maybe 4-5000 km on them, maybe half the tread depth left).

Tonight it was even more pronounced than usual. I have the front preload backed off a tad from standard and the rear preload about two and a half (silver lines) from fully cranked. (Silver lines are on remote preload adjuster from ABS models).

The bike isn't very stable in a straight line... really sensitive to any irregularities in the road surface. Wind really moves her about.

It's odd because with the front lowered, I can understand it might be a little less stable than normal in a straight line, but then there's this contradictory tendency to want to stand up straight :warranty: :fing02: :beer:

Goin' bonkers over it...

[Guest]

a little more specificity is required. You need to explain the action in a little more detail. Is it under throttle or not?, are you trail braking into the corner?, is it at the apex or the exit? You seem to have more than one thing that could be causing your problems, just want to make sure I fully understand what/when it is doing, what you don't like. If you are willing to provide explicit detail, something can be worked out.

The things you are explaining are caused by a combination of things and aren't related to any one thing. It would seem that some of the problem is caused by rebound damping, but some of the other things are geometry related.

[HispanicSlammer]

Lets see here, you raised the forks in the triple, then you negated that effect by cranking on preload? Just set the forks back to stock and check the sag so that it is 30-35mm, your counteracting your mods here. Then set the rear shock to 30-35mm of sag and go from there. Get a baseline then work from there.

[spud786]

My tubes are raised about 10mm, actually couldnt be raised any more without dust seals hitting the bottom tripple clamp. Bike rock solid high stability wise.

I have not run 15 weight in this bike, if that oil is thicker than ss8(each brand varies so much) and you didnt adjust the oil height , like 110 mm , you probably have an overly stiff fork with slow rebound.

By removing all your preload, your actually running deeper into the harsher part of the stroke.

If attempting to run the standard preload and is yeilding a super stiff fork , id try reducing your oil height. You can do this in the bike by removing the caps on the fork, have enough room to suction like a straw with some tubing , carefully measure the amount coming out, I'd try 5 cc increments , but sounds like 10cc if its that stiff. (only remove cap of one fork. removing both front end may collasp

Thats what sounds like is happening, your defecting the bump instead of absorbing.

[HispanicSlammer]

15 wieght? what possessed you to use that? 10w is stock and now your ride is harsh? No kidding man its the oil. Stock springs and valves plus heavier oil = harsh ride! I would redo those forks with the proper oil, it is possible you had some worn out oil in there before and then overcompensated with the 15w? In any case as long as you use that stuff you might as well weld the fork tubes together, same effect.

[Guest]

As stated by HS, you need to have a baseline setting that gets your sag numbers into the correct range. This will help to make sure that the spring is correct and that the fork is riding in the correct part of the stroke. After you get the sag set, put a zip tie on the fork tube and take it for a ride, this will give you an idea of how much of the travel you are actually using.

The fork oil can be used for a couple things. The height and the weight of the oil actually works in conjunction with the spring to control the forks action in the last 25% of travel. The oil's primary function is to control the air volume in the fork.

The oil height is critical. It is the airspace above the oil that needs to be scrutinized. The more airspace you have, the softer the fork will be in the last 25% of the stroke, the less airspace you have, the stiffer it will be. So it is possible to fine tune this part of the stroke by using different weights of fluid, coupled with different heights.

This helps to tune things so that you don't have to mess around with the preload, which pays a penalty in changing the chassis geometry. If the oil is too high, you will not be able to get to the very bottom of the suspensions available stroke, sometimes just 10mm in height change will hit the sweet spot. By varying oil weights and heights you can tune the very end of the stroke, this is usually where people feel the harshness and lack of feel.

[Auspanglish]

Hmm, certainly

a little more specificity is required. You need to explain the action in a little more detail. Is it under throttle or not?, are you trail braking into the corner?, is it at the apex or the exit? You seem to have more than one thing that could be causing your problems, just want to make sure I fully understand what/when it is doing, what you don't like. If you are willing to provide explicit detail, something can be worked out.

The things you are explaining are caused by a combination of things and aren't related to any one thing. It would seem that some of the problem is caused by rebound damping, but some of the other things are geometry related.

Not sure at what point it is taking place. I don't usually trail brake. I might hazard to say it's under acceleration, but like I said, not 100% sure... will try to discern when it is exactly and post up.

Lets see here, you raised the forks in the triple, then you negated that effect by cranking on preload? Just set the forks back to stock and check the sag so that it is 30-35mm, your counteracting your mods here. Then set the rear shock to 30-35mm of sag and go from there. Get a baseline then work from there.

No, I don't have the preload cranked up. Like I said I actually have it backed off a tad (maybe a 360º turn) from standard. I have tried using more preload in the past (before raising the tubes in the trees) and besides, tend to use more preload up the back so... I did have the sag set but have since lost the reference, playing around with it all and recently taking pillion and heavy tankbag on trips... to then later use her as my daily commute (the bike that is hehehe) so the setting is porbably out... will try again... although I recall having some difficulty in achieving proper sag and started thinking the springs must not be right for me... although I only weigh 90 kg, got to add on gear and tankbag... anyway, will try getting her back to proper sag...

My tubes are raised about 10mm, actually couldnt be raised any more without dust seals hitting the bottom tripple clamp. Bike rock solid high stability wise.

I have not run 15 weight in this bike, if that oil is thicker than ss8(each brand varies so much) and you didnt adjust the oil height , like 110 mm , you probably have an overly stiff fork with slow rebound.

By removing all your preload, your actually running deeper into the harsher part of the stroke.

If attempting to run the standard preload and is yeilding a super stiff fork , id try reducing your oil height. You can do this in the bike by removing the caps on the fork, have enough room to suction like a straw with some tubing , carefully measure the amount coming out, I'd try 5 cc increments , but sounds like 10cc if its that stiff. (only remove cap of one fork. removing both front end may collasp

Thats what sounds like is happening, your defecting the bump instead of absorbing.

No I did not adjust the height... used the same 100 mm reference from the tube top to the oil as per 10W. I felt the 15W was too stiff straight away. although it FELT like an improvement over the old oil. I haven't removed all the preload, just backed it off a tad of the standard position.

15 wieght? what possessed you to use that? 10w is stock and now your ride is harsh? No kidding man its the oil. Stock springs and valves plus heavier oil = harsh ride! I would redo those forks with the proper oil, it is possible you had some worn out oil in there before and then overcompensated with the 15w? In any case as long as you use that stuff you might as well weld the fork tubes together, same effect.

Well, several folk supposedly in the know encouraged me to do so due to the +40ºC summers over here and swore by the improvements they noted... True, the front was feeling like it had very little rebound damping and I wanted more... but of course the 10W was worn. I have since been known to say I feel it was a mistake, but can this really have the bike standing up so??

Maybe so... I'm thinking it's a combination of two of all your comments, having the weight of the bike transferred forward due to lowering the front... and less preload, has the fork-tubes running towards the end of their run-out and working in what is now a "harsher zone" (due to oil height not modified accordingly on increasing oil density)... and because the thicker oil isn't allowing the forks to extend in time for successive bumps, it loses all capability of absorbing subsequent impacts, and thus, like hitting the brakes too hard, the bike wants to stand up...

Does that compute??

I had already made plans to go back to 10W... would really like to get custom springs but no cash... the wierd thing is that, if fork oil loses its properties over time, and I ride the bike quite hard... this oil should be fairly worn by now... and it didn't do it when I first put the oil in... that's why I wasn't so sure...

Oh, and I forgot to mention, I have conical steering head bearings installed instead of the OEM ball-type ones... sorry, forgot to mention that... could this compound things as well?

I do appreciate all your comments.

[Guest]

ENTERING A CORNER:

Chassis resists leaning while trail braking:

Cause - Insufficient Rake

Possible fix Increase rake by lowering rear ride height, reducing rear preload. Lowering the forks in the triple clamps or adding front preload.

CORNER EXIT

Bike runs wide or is unstable over bumps

Cause - Excessive squat is causing the front tire to lose traction

Possible fix: Reduce squat by adding rear preload, adding rear ride height, raising the fork tubes in the triple clamps or adding front rebound damping

STRAIGHT

Chassis feels loose and loses traction, or is unstable over rough pavement

Cause - Insufficient rebound damping

Possible fix: add rebound damping

BRAKING

Lack of feel from front end

Cause - Not enough weight transferring to the front tire

Possible fix: Remove fork oil or reduce front preload

As you can see, the adjustments can be counter productive without knowing exactly what the issue is.

Preload adjuster does not change the spring rate, the spring rate will not get stiffer by adding preload, it is a ride height adjustment. Adding 10mm of preload to your fork spring, will raise the height of the front of the bike 10mm. As long as the forks aren't topped out or bottomed out, dialing in more preload does not compress the spring more, it raises the bike on it's suspension an equal amount - raising the ride height.

I think you have left the reservation in terms of your setup, the first thing you need to do is get the recommended fork oil weight and height corrected to stock, set the sag and get the rebound adjuster set in the middle of it's adjustment. After you get this done, start making little changes. Make sure you keep accurate notes so that you can get back to an earlier setting if things start to come off the rails like they are now.

[Auspanglish]

Thanks mate... hte more coherent info I have the better... I'll be working on this issue as soon as I can and report back up...

[checksix]

ENTERING A CORNER:

Chassis resists leaning while trail braking:

Cause - Insufficient Rake

Possible fix Increase rake by lowering rear ride height, reducing rear preload. Lowering the forks in the triple clamps or adding front preload.

CORNER EXIT

Bike runs wide or is unstable over bumps

Cause - Excessive squat is causing the front tire to lose traction

Possible fix: Reduce squat by adding rear preload, adding rear ride height, raising the fork tubes in the triple clamps or adding front rebound damping

STRAIGHT

Chassis feels loose and loses traction, or is unstable over rough pavement

Cause - Insufficient rebound damping

Possible fix: add rebound damping

BRAKING

Lack of feel from front end

Cause - Not enough weight transferring to the front tire

Possible fix: Remove fork oil or reduce front preload

As you can see, the adjustments can be counter productive without knowing exactly what the issue is.

Preload adjuster does not change the spring rate, the spring rate will not get stiffer by adding preload, it is a ride height adjustment. Adding 10mm of preload to your fork spring, will raise the height of the front of the bike 10mm. As long as the forks aren't topped out or bottomed out, dialing in more preload does not compress the spring more, it raises the bike on it's suspension an equal amount - raising the ride height.

I think you have left the reservation in terms of your setup, the first thing you need to do is get the recommended fork oil weight and height corrected to stock, set the sag and get the rebound adjuster set in the middle of it's adjustment. After you get this done, start making little changes. Make sure you keep accurate notes so that you can get back to an earlier setting if things start to come off the rails like they are now.

Wow: condition...symptoms...possible cause...possible cure

This is the most informative and succinct post I've seen in one place on suspension behavior. I just saved a copy. Nice job.

[turtlecreek]

The first step is setting proper sag. This simply refers to how much the bike 'sags' when you sit on it. Sag is always measured from the fully extended position. Lever the wheel off the ground, measure, sit on the bike and measure again: That's "Rider Sag." "Static Sag" is how much the bike sags all by itself. Putting a zip-tie around one of the fork legs simplifies measurement and can be left in place so you can see how much suspension you are using.

Since damping can/will effect your readings, you should set sag with the damping dialed to fully soft. Be sure and write down your settings so you can return to them when you are done.

You’ll need 2 people to help you do it accurately, but the mechanics of setting sag are simple: One person levers the back of the bike off the ground on the sidestand and front wheel, while a second person measures the total available travel of the swingarm from the axle to whatever part of the bodywork/frame is convenient. It is important that you pick a spot that’s directly above the axle. I like to write an ‘X’ on a piece of masking tape to be sure I’m measuring the same thing every time. Write that number down, as it is your baseline. Then you sit on your bike in your normal riding position, ideally wearing your gear. One helper steadies the bike, while the other repeats the measurement you just made. Subtract the second number from the first, and you’ll have the amount the bike is actually sagging under your weight. Add or subtract spring tension at the shock until you get the number you are looking for. That accomplished, you would then repeat the process for the front forks. As I mentioned above, a zip tie around the swept area simplifies measurements.

For a streetbike, I've found that 40mm up front and 30mm in the rear is a good place to start. Track mavens would/should start around 30/20~25. Since it's the more important, set rider sag first, and then go back and check static sag - The bike *should* sag a little by itself: 5~10mm is good. If you have proper rider sag but no static sag, then you have to wind your springs too tight, and you should install heavier springs. More than 10mm static sag and you should think about going to a lighter spring.

If you want to be really precise, you'll factor in suspension 'stiction' as well. Stiction refers to the amount the suspension sticks because of internal friction. With the bike roughly dialed in, and you sitting in riding position, have a buddy press down on the triple, and release. Measure. Then have him lift UP on the front and allow the bike to settle again. Take the average and use that as your baseline. A 0~5mm difference is considered very good. More than 5~10mm is OK, but you might check your methodology and look for things that might be misaligned. If you're closing on 15mm of stiction or more, you have a real problem and should take your bike to a pro for a rebuild. (But you probably already knew that 'cause your bike handles like crap!!!) Repeat for the rear.

I've had my best luck setting the rear first and then doing the front.

NEAT SAG TRICK: Put your bike into a long fast sweeper on neutral throttle and relax your grip on the bars as much as you dare. The bike will likely make a movement:

If it falls into the turn: You are setup favoring initial turn in over side to side flickability. Add front preload to move to neutral.

If it stands up: You are setup favoring side to side movements over initial turn-in. Remove front preload to more to neutral.

Where you end up with that is rider preference. Note: The movement I'm describing should be slow. If the bike darts one way or the other, then you should head back to the garage and re-check what you've done.

Since doing the job properly takes a couple buddies, it makes sense to do everyone's bike at the same time.

Damping Settings

Once you have set your springs properly, then you can move on to damping. You *did* write down your settings when you set sag, right!?!?! Normally, your owner's manual will have some baseline settings, but if that's not available, you'll have to come up with your own.

I'll start with Rebound: A ballpark 'Guesstimate' is shove down on the front while holding the brake and allow the bike to spring back on it's own - It should rise back up, but make NO additional movement. If it does, add rebound. If it does not, take rebound away until it does, then add back just enough to stop the excess movement. Rear rebound: Shove down on the back of the bike, no brakes: It should take about 1 second to rise back up.

Compression settings are more open to interpretation. I like JUST enough up front to stop excess diving on the brakes. You'll have to ride to determine that - try 1 turn from full soft and play from there. You'll want to balance the front and rear, though - Bounce lightly and heavily on the bike with both brakes on and have a buddy stand off to the side watching you. Interfere with the bike's movement as little as you possibly can: Your buddy is watching that both ends of the bike rise and fall together.

VERY IMPORTANT - Suspension tuning is an iterative process, meaning that 1) as you make changes, the changes you make may require to tweak a little more, 2) As you progress as a rider, your damping requirements will change (generally stiffer the more aggressively you ride), and 3) Riding in different situations requires different settings: Most obviously one setup for the street and another for trackdays. Even then, as you improve, your trackday settings will likely change as well. What works when you're running 1:55's may not control the bike properly when you up the pace to 1:53’s.

This little fact of life means that it is very important to keep track of your suspension settings and what changes you make over time. That will ensure you can play around with different setups and still be able to return to where the bike was before should you need to. Those who may be REALLY serious would also add columns to their notebook about the specific results the changes they made gave them. That's not necessary for most riders, though. But DEFINITELY keep a little notebook - You won't remember your settings.

GENERAL RULES

1) Once proper spring sag has been set, and you have damping you can live with: Put the bike into a long, fast sweeper on neutral throttle and relax grip on the bars as much as you dare. If the bike stands up, decrease front spring/increase rear spring/height to bring bike to neutral. If the bike falls in, do the reverse

2) SLIGHTLY harder rear compression helps the bike to turn in faster

3) AFTER you have the bike to the point where it does nothing bad, look to balance all the damping so the ends work together. It should only take a click or two

4) If the wheel is bouncing and you cannot really feel it through the bars/bike - That's a lack of rebound. If you *can* feel it through the bars/bike, Too much compression

5) If the problem occurs from steer-in to midpoint, then change the front. Mid-point to exit, start with the rear.

6) If the bike is too high in front, it will take more effort to steer it and you will have to hold it down. Raise your forks in the triples

7) If the bike is too low in front, it will steer dramatically and try and drive off the inside of the track. It will be unstable all the way through the turn. Lower your forks in the triples.

If the swingarm is too flat, the bike will squat too much. The bike will try and run wide as you exit the corner. The front end will feel light and try to dance around. Add ride height in rear/lengthen shock absorber

9) If the swingarm angle is too steep, then the bike will not squat enough, and you will experience poor traction: Wheelspin on corner exits. Lower rear height/shorten shock

10) If the bike isn't acting balanced, adjust it until is does - REGARDLESS of your initial adjustments. Balance should be maintained whether you bounce lightly or with great force.

Front Rebound

TOO MUCH REBOUND (FRONT)

- Front end feels 'Locked Up,' Harsh Ride Quality

- Suspension packs in and fails to return – Typically after the first bump, the bike will skip over following bumps and want to tuck the front

- Bike prone to Headshake and Tankslapping upon hard acceleration

TOO LITTLE REBOUND (FRONT)

- Forks are plush, but increasing speed causes loss of control and traction

- Bike wallows and tends to RUN WIDE EXITING turns

- Front end CHATTER, loss of Traction

- Slow to recover on Aggressive Input

- Wheel KICKS BACK on large bumps

Front Compression

TOO MUCH COMPRESSION (FRONT)

- Front End tends to ride high through corners, causing the bike to steer wide

- Suspension is harsh over small bumps

- Front end Chatter on corner entry

- Bumps and ripples are felt directly

- Suspension is generally harsh, and gets worse on braking and entering turns

- Forks don't use enough suspension to properly absorb bumps

- Forks never seem to bottom out, even on large hits

- General lack of traction can cause overheating tires

TOO LITTLE COMPRESSION (FRONT)

- Front end DIVES SEVERELY

- Front feels Soft or Vague

- Bottoms out on medium-sized bumps

- *Clunk* can be heard upon bottoming

TOO MUCH REBOUND (REAR)

- Wheel tends to hop in turns with small bumps

- Wheel skips too much when braking on rippled pavement. Does not develop good braking power

- Poor rear traction when accelerating over small bumps or rippled pavement

Shock may 'Pack Down' - Too much damping keeps the wheel from extending enough before the next

- Suspension Gets harsh over medium or large rolling-type bumps at speed

- The first few don't feel bad, but after that the suspension gets harsh and starts jumping around

- Rear and can Pack In under acceleration, causing the bike to run wide under power

- Rear "Swims" under hard braking

TOO LITTLE REBOUND (REAR)

- Bike wallows when exiting corners or in long rolling dips in sweepers

- Bike feels soft or vague

- Rear pogo or chatter on corner exits, general loss of traction, and tire overheating

Rear Compression

TOO MUCH COMPRESSION (Rear)

- Suspension seems rigid, instead of absorbing

- Suspension is harsh over small bumps

- Wheel skips when braking hard on rippled surfaces

- Very little squat - Loss of traction/sliding

- Tire overheating

- Suspension is harsh over pavement changes

- Shock stays too rigid and doesn't use enough travel to absorb bumps

- Shock rarely or never seems to bottom out – Even on the biggest bumps

- Bike Kicks on large bumps

TOO LITTLE COMPRESSION (REAR)

- Shock bottoms out on Medium-sized bumps

- Rear squats under acceleration

- Bike doesn't want to turn upon corner entry

- Excessive Squat under power – UNDERSTEER

[Vee-Ef-Ar]

Thought I would come back and see how you got on Auspanol.

77,000kms... not too stable in a straight line, little road irregularities making you not happy... mine is starting to do this. I wouldn't say it's standing up in the corners, but it's unhappy near the apex... at a spirited pace the front feels like the road is dictating the bars {only slightly), sometimes I need to counter her in more, other times it just suddenly dips more than expected... which at this point it feels very vague... like entering a slide, but I know I have pushed the front harder before.

I too did the front forks... 7.5wt, forks raised bout 10mm and installed the taper head bearings.

I was going to suggest you check/change the wheel bearings... that is my next step.

[Auspanglish]

Thought I would come back and see how you got on Auspanol.

77,000kms... not too stable in a straight line, little road irregularities making you not happy... mine is starting to do this. I wouldn't say it's standing up in the corners, but it's unhappy near the apex... at a spirited pace the front feels like the road is dictating the bars {only slightly), sometimes I need to counter her in more, other times it just suddenly dips more than expected... which at this point it feels very vague... like entering a slide, but I know I have pushed the front harder before.

I too did the front forks... 7.5wt, forks raised bout 10mm and installed the taper head bearings.

I was going to suggest you check/change the wheel bearings... that is my next step.

Yeah Mate... sounds real familiar... the wheel bearings were up high on my list of things to check or just swap out anyway... unfortunately I haven't had time or the inclination to hardly even ride her lately (the bike ehhh)... I don't have a car but am on holidays and studying for nursing exams so I haven't had time to get stuck into to changing fork oil and bearings and stuff and then set-up proper sag and then get out and ride to see how it goes...

But I have really been impressed by the input provided by the folk here, lots of interesting reading.. thanks a million... I promise I'll post up when I have something to add regarding mods and improvements made over the coming months... probably get stuck in just after exams in a few weeks time...

A big "G'day" to ya from an Ex-North-Queenslander!!

[PorradaVFR]

My initial reaction was simpler - are your tires squared off? The problem getting worse over time could = miles added to rubber.

[The Phantom]

The tyres/fork oil combo may be the issue here - with some wear on the shoulders and that heavy oil, you may get some undesirable characteristics.

That said, the first thing I'd do is ensure that the steeringhead bearings are correctly adjusted... tapered bearings in particular need some follow-up attention after you've put a few miles on them. At the same time I'd return the forks to their factory-set level in the triples (I'll come back to this).

Then clean, lube and set the chain tension correctly, and return the suspension to stock settings then set sag for your weight.

Take it for a ride and see how it behaves.

A better solution to make it turn in a bit quicker is to leave the front end at the stock height, and slip a shim or two between the top of the rear shock mount and the frame - this has the added benefit of increasing ground clearance rather than reducing it.

[Vee-Ef-Ar]

Yeah Mate... sounds real familiar... the wheel bearings were up high on my list of things to check or just swap out anyway... unfortunately I haven't had time or the inclination to hardly even ride her lately (the bike ehhh)... I don't have a car but am on holidays and studying for nursing exams so I haven't had time to get stuck into to changing fork oil and bearings and stuff and then set-up proper sag and then get out and ride to see how it goes...

But I have really been impressed by the input provided by the folk here, lots of interesting reading.. thanks a million... I promise I'll post up when I have something to add regarding mods and improvements made over the coming months... probably get stuck in just after exams in a few weeks time...

A big "G'day" to ya from an Ex-North-Queenslander!!

A big G'day back to ya from a 10 yr Registered Nurse... good luck with the exams mate and the bike. Just last night I confirmed the noise from the front is actually the bearings. I thought it might have been the tyre coming to its end (commuter Dunlop GPR thing) they seem simple enough the change out and they're probably due anyway... 83,000kms.... the tyre not far off, so a clean change and go from there.

That said, the first thing I'd do is ensure that the steeringhead bearings are correctly adjusted... tapered bearings in particular need some follow-up attention after you've put a few miles on them. At the same time I'd return the forks to their factory-set level in the triples (I'll come back to this).

Phantom I went back and lowered the forks 5mm and reset the bearings. All was nice and snug... but the symptoms were the same.

Then clean, lube and set the chain tension correctly, and return the suspension to stock settings then set sag for your weight.

Front and rear suspension reset to stock, had the misses help me with the sag. Pretty sure we got that right... I went an extra step up on the rear preload, and backed the rebound off slightly less, the rear feels better than ever, all on the same PR2. I've been playing with the front preload for a week or so now, but symptoms persist.

A better solution to make it turn in a bit quicker is to leave the front end at the stock height, and slip a shim or two between the top of the rear shock mount and the frame - this has the added benefit of increasing ground clearance rather than reducing it.

I've been meaning to do this, mainly so I can come back to stock height on the front, and have slightly more leg stretch when stopped. Got any idea on how much?. There's no real consensus, variables with everyones front ride height, and personal preferences. ALOT of threads.

Also, the symptoms are present with both new and old tyres... infact my old tyre chopped out on the right side, hence the headstem bearing change... the new tyre has worn well evenly, but the symptoms persist. The wheel was balanced and came up almost perfect before weights.

I'll add my thoughts after the changes... Some good advice from all here. Thank you.

[Guest]

Great input guys!

One thing I would like to add to the process of measuring sag. Purchase a Baxley wheel chock (these will hold the bike in an upright position by grasping the front tire). If you put the Baxley lock pin in the front most position, it lifts the front end exactly one inch.

Take two pieces of 12" x 12" half inch plywood and make a one inch thick platform for the rear tire. That way you can sit on the bike, assume the correct riding position, and you only need one other person (wife or girl friend) to read the sag measurements.

Note of caution here (and please ladies, don't flame me), make sure your wife/girl friend knows how to read a tape measure. 48 and two hickies is not a measurement. Teach them that means 482 millimeters. Never refer to the zero end of a tape measure as the "stupid end" to their face. :biggrin:

After about 5 times, my wife can read sag with the best of the suspension gurus. I just say "Let's do some sag measurements" and she knows what to do. :fing02:

[VFR Capt.Bob]

If the forks aren't compressing normally under cornering loads that will cause the bike to be difficult to turn in. As the back wheel compresses normally or extra hitting a bump the bike will want to stand up and run wide.

I'm guessing since you only changed the forks set up that your problem lies there. Get that heavy oil out of there and check the level carefully. I had Race Tech set up my front end after I'd suffered my own inept set ups. Well worth the investment.

Lowering the front will only aid intitial turn in. Does nothing for stability. I think your fork oil is forking with your bike.

[The Phantom]

If the forks aren't compressing normally under cornering loads that will cause the bike to be difficult to turn in. As the back wheel compresses normally or extra hitting a bump the bike will want to stand up and run wide.

That makes perfect sense :unsure:

I've been meaning to do this, mainly so I can come back to stock height on the front, and have slightly more leg stretch when stopped. Got any idea on how much?. There's no real consensus, variables with everyones front ride height, and personal preferences. ALOT of threads.

Depends on what you can get as shims. I got mine from a Beaurepairs, three shims at 1.5mm per shim. I used two, 3mm at the shock gave me 12-15mm of lift at the tail light (approx) and it felt pretty good like that.

I meant to try 4.5mm but never got around to it... I think it might have been a bit much for road riding, maybe good at the track.

They look a bit like this, I knocked off the tabs at the top and cleaned them up a bit to install.

[Vee-Ef-Ar]

Thanks for the tip Phantom, I got some, but haven't had time to even look at the backend. Reminds me I should get my (his) preload spanner of vfrr.

Anyway, I've buttoned her all back, forks rebuilt, new stem and wheel bearings, new front conti RA.

There was definate improvement, especially mid corner where I would feel the bike suddenly drop in, or start creeping wide... sometimes I'd have to weight the pegs and really fight her to stay on my choosen line. Maybe the conti needs more of a scrub, but there is very little feedback into the palm of my hand through the bars now. It used to push and pull, but now it's much more balanced, and I'm not having to fight it. Front bearing noise is gone. Tyre wear will be monitored.

Even with our $hithouse roads and streets, the bike is much more balanced when hitting lumps and bumps in straight line. I will need to ease up some preload though as the conti feels much more stiffer than what I've used before. The 021 was stiff, but this feels more. Damn good tyre so far. Turn in was much faster than I've every experienced.

Front braking is probably the most noticeable improvement, much more even just before stop with a little waggle, which I've put down to my tall stature balancing as I take a foot off the peg, otherwise it's plumb.

Now to sort this rear end.

[Auspanglish]

Nice to see that things have improved for you Vee-Ef-Ar... I still haven't had time to do anything with mine (half way through exams: Celular Biology, Histology (including microscopy prac) and Nursing Basics (Nursing Diagnosis, Dressing wounds, Virginia Henderson's 14 Needs, NANDA NIC NOC, Making beds, simple background stuff), all passed so far... History of, Anatomy and Methodological Foundations (head trip) to go.

I did drop in at my trusted Triumph mechanic's and have him go over the bike... he felt there was nothing wrong with the either the steering or wheel nor the swing-arm bearings, felt preload and rebound damping was correct, the front forks compress under extreme braking to a correct degree (zip-tie on front fork tube)... the only thing he felt could contribute to my woes is the denser fork oil... which coincides with several opiions from here... hoefully in two weeks' time will be able to swap that out and test her at a track day in Albacete...

[Guest]

preload and spring rate, just cause you have the right sag doesn't mean your spring is right....

We can use the concept of "Free Sag" to use the geometric attribute of Rider Sag to predict and tune the suspension attribute of spring rate. By examining the change in the bikes sag measurements with and without the rider, we can determine the change in equilibrium positions of the wheels. By using some basic conventions, we are able to tune for the appropriate spring rate. Just to use some imaginary numbers, lets say that the rider and gear weighs 200lbs. and the sprung weight of the bike (with gas) is 350lbs. In this case, the bike alone is 60% of the weight that the spring must hold up. At rest roughly 2/3 of the rider's weight will be upon the rear wheel, so the change in the Free and Rider Sags will be greater at the rear.

The rate of the spring is critical. If desired Rider Sag is 35mm and desired rider contribution to the sag is 15mm, then accordingly Free Sag should be 20mm. Any spring will give you 35mm of Rider Sag, given some preload position, but only one spring (rate) will also give 20mm Free Sag with the same preload position. In other words, given specific goal numbers, only one correct spring rate exists.

But that being said everybody seems to talk about changing worn out fork oil but never has the rear shock serviced. That oil goes bad too...

So where to start...if it where me

1. Pull the rear shock and have it serviced.

2. Pull the forks and check the springs for correct length,

3. New seals and wipers...

4. Check bushing replace as needed

5. New fork oil Honda SP8

that will give you a baseline to work with and the knowledge that the internals are good...Just my to cents

Dan

[u20overboy]

Excellent information in this post. Its one thing to have better after market components but set up is key. I for one plan to do more adjustment this spring to see how much I can improve my ride. Thanks to all who posted.If I told my wife we are going to measure sag at our age she would say I have a headache :goofy:

[Baileyrock]

The rate of the spring is critical. If desired Rider Sag is 35mm and desired rider contribution to the sag is 15mm, then accordingly Free Sag should be 20mm. Any spring will give you 35mm of Rider Sag, given some preload position, but only one spring (rate) will also give 20mm Free Sag with the same preload position. In other words, given specific goal numbers, only one correct spring rate exists.

Dan

:goofy: So true Dan, this is the point Pete & I keep trying to get across to everyone! Most people think if you can get desired Rider Sag then the Spring is correct, but just as you've mentioned rider sag is meaningless for calculating correct spring rates w/o also having the desired Free sag numbers!

The other fact is that just because some Tuner or even Ohlins or Penske says you need "....lb spring" does Not mean it's the correct one unless you get Both the desired numbers for Free & Rider Sag! Elka sent many of our members new shocks with the wrong spring rates on them and now if anyone ever bothered to check the numbers they have found them to be wrong and are needing new springs! Of course a New Aftermarket shock will feel better than a stock VFR shock, even with the wrong spring, but you are paying for the correct spring rate and Most are Not getting it!

I've seen different Pro's suggest for our members VFR's rear spring rates from 800lb to 1400lb springs for the same 190lb rider! :goofy: That's insane! There is only one correct rate for that rider on his VFR and every other spring rate recommendation is WRONG whether it's Ben Speis, Ohlins, Penske, me or the best tuner in your country telling you so.

The ONLY way to know if the spring rate is correct is on the bike and checking both Free & Rider Sag, there is no other way!

I've said this in other threads, I think the problem is that most Pro's have a faulty spring rate calculator for the VFR model only and constantly come up with these bogus numbers. Almost always Too soft. :ph34r:

[Guest]

Thought I throw this out

Rider Sag = Measured sag of bike and rider w/ rider and rider's gear.

Free Sag = Measured sag of just the bike, no rider, no rider gear.

Note - It may help to set all the slow speed damping adjusters to full open when setting sag.

SPRING RATE -

Spring Rate OK - Both free and rider sag within acceptable range.

Spring Rate too soft - Rider Sag OK, but too little or no Free Sag

Spring Rate too firm - Rider Sag OK, but too much Free Sag

SAG -

Front -

Rider Sag - 30-35mm (25-30% of Full Travel)

Free Sag - 15-20mm (60-70% of Rider Sag)

Rear -

Rider Sag - 20-30mm (race), 30-35mm (street) (25-30% of Full Travel)

Free Sag - 5-10mm (extremely light bikes use less) (15-25% of Rider Sag)

Dan