Quick Help...preferred Fork Height & Mechanic Working On It Now

[Cmac]

Hi all. I have my 6th gen bike in the shop being getting new Race Tech springs and valves in the forks as write this. Also, getting Leo Vince exhaust.

I just got a call from the mechanic, to let me know the forks were lowered 17.5mm from stock. He was checking with me to see if I had that adjusted down like that on purpose, and he thought it was way too much. I let him know that was new to me, and it must have been the 1st owner. The only thing I did was have different shop install heli bars after I bought it last year, but there was never a discussion about adjusting fork height. By the way, I am not much of a suspension guy, and the only thing I know about suspension is the from reading this forum (which is great!). So, the mechanic said he would put the front forks at 5mm below stock. Oh, and I'm having a Penske 8983 +5mm installed too.

My riding is aggressive street riding, and a few track days. I scrape the peg feelers now and then, and want to do what I can to mitigate the risk the best I can from bottom out from scraping the pipes that could lead to crash.

I have heard from other postings that a +5mm in rear shock is a preferred setting quicker turn in and aggressive riding. What about the forks? Is there a preferred setting? The shop is working on it right now, and are going to do 5mm below stock. I though I would see if I could get a few quick experienced response from the forum in the next hour. If 5mm down on the forks is not preferred, I'll call the shop back and have it changed.

I am so looking forward to my suspension and exhaust upgrade!

Thanks.

[Duc2V4]

According to my service manual (2002+), the height above the triple tree is 41mm. Rasing the rear or lowering the front (i.e. raising the height above the triple tree) will quicken the steering. Doing them both at the same time might make it too quick and/or your high speed stability may suffer a little. I would start at stock and see since the rear is coming up a little anyway. YMMV

[Cmac]

Thanks. Since I'm having the front actually raised from the current 17.5mm lowered to 5mm lowered. I was wondering if my turn would actually be a little more sluggish from what I'm used to, even with the new Penske rear shock that will be 5mm up from stock.

Thanks again.

[zRoYz]

Some help, the reason to lower the front or raise the rear manually is to help with ease of turn in or how quick the bike will shift to the edge of the tyre with applied force to the bars. The more you lower front or raise rear the less force needed to transfer to tyre edge.

Now on saying that there are many more factors involved like spring rates, valving settings & your dynamic/static sag settings which also have the same effect, for example front braking drops the front & will raise rear which also has the same effect on corner entry. It is a rider preferred setup no one can give you a setting that just works because we all like different things & credit to your mechanic for pointing out the extreme setting you have because if forks still stock & your increasing spring rate for your weight then the front would have been sagging extremely anyway on braking & corner entry.

The best way to do the manual setting before preload etc adjustments is raise the rear only, it is always best to raise rear than lower front on the VFR due to ground clearance issues if your a corner monkey. Then set sag settings & go for a ride & gauge the turn in effort, if you feel it is to sluggish then raise the rear a little more but you are limited on the VFR due to dog bone & remember 5mm extra shock length is about 20mm extra height rear. I wouldn't raise the rear higher than the available gap you have with rear on centre stand so max is tyre just touching ground when on centre stand mainly because you want your centre stand to work. Note any height adjustment you make you need to redo your sag settings as the front rear loading changes.

If your still not happy with turn in feel when you max out rear height setting then lower front but I suggest 5mm only to start then 3mm after that but with rear raised to max I wouldn't think you will need much more than 5mm & I wouldn't go more than 10mm from stock height with rear max. You tend to know if you go to far as your bike will feel like it wants to flop over on it's side to easy like you need to add input to correct it & the rear can feel lose but not so much on the VFR because of weight & the geometry is so neutral to start with.

So nut shell raise rear if needed to max before wheel hits ground on centre stand & only lower front as little as possible if required but only go as little as needed for feel & remember you are meant to use bar input to steer. On a side note it is always best to first setup a bike with new or slightly worn tyres so you know the feel, doing so with worn or cupped tyres will mean when you replace your bike will feels way to responsive & you may have to start again. Your meant to feel sluggishness from worn tyres it is the alarm bell there getting past there use by date. Also there is any other side effect going to far your bike will tram track on lines on road surface.

[HighSideNZ]

One thing to remember is with the stock front springs the amount of sag is extreme so the front end is alway low.

What I found when I installed my AK-20 internals and .95kg single rate springs, if I set the fork height by the manual at 41mm above the top clamp, the bike would not sit on the centre stand. EG: the front sat much higher than stock.

To overcome this I dropped the forks further thru the clamps.

What I eventually did, once I had a Ohlins in the rear and my static and rider sag set correctly, I added 5mm to the feet of the centre stand and then lengthened the rear shock by 1mm (4mm at the wheel) to quicken the steering to what I like.

The change in front springs will alter the geometry dramatically so keep that in mind.

[Cmac]

Thanks for the input! I left the front forks at 5mm down for now. Now i'm just waiting for the Penske +5mm to be delived in a couple weeks. Then I can see how it all comes together. Also, I've got some new Michelin Power Pilot 3s.

[CornerCarver]

Cmac after you have it sprung for your weight and set the sag (again for your weight) get in a few rides. If you don't immediately think the steering is much slower than when set at 17.5mm below stock then the rear being raised and properly sprung has helped you immensely.

After a few spirited rides, check the chicken strips front vs rear (not yours vs a friends) and see if your bike is "balanced".

If, for example you find that the rear tire is worn within 1/8" of the edge but the front is still 1/2" from the edge then you can see that by dropping the bike on teh forks a liitle you can quicken the steering a bit and utilize more of the front tire.

The VFR is so stable that it is very difficult to drop it so much that the handling becomes hyper sensitive. I found that my front wheel came in contact with the head before the handling felt squirrely.