Geometry adjustment: Rear spring perch or slide forks in triple clamp

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accel_is_my_drug

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Bike Geometry question...

I wish my 2006 FZ1 felt a bit more like a full on sport bike. I feel like the front end is a tad vague.. I think because I feel that not enough weight is on the front end.

Whats the difference in geometry changes between raising the adjustment on the rear spring perch ( that i think raises the back of the bike, and therefore steepening the head angle)

And lifting the forks up in the triple clamp by a few mm. also tightening up the front head angle... Seems like up to 8 mm of fork leg showing above the triple clamp is OK.

Anyone have any recommendations? I am going to eventually try to drop the bars, by either a set of low risers or something like the speedymoto tallboy 50mm clip ons to try and put some more weight no the front end..

What else can I do?

Anybody have any recommendations?
 
the traditional method is to raise the forks through the trees a little bit.... but you can also use shorter dogbones on the rear shock to raise the rear... the only thing you have to watch for is that if you lower the front (by raising the forks in the trees) or raise the rear too much, it'll be less stable... you're looking for that magical spot that allows it to be very "flickable" ... but still stable.

I'd start with the front... drop the forks through by 5-7mm ... see how that feels... then, if needed, you can start playing with the rear... the issue with the rear is that the adjustable dogbones tend to not be so great... so, you'd have to buy multiple sets, or make your own dogbones...
 
Upping the preload on the spring is not the proper way to change ride height.

On the rear, you want to change the dogbone length.

Dropping the forks / raising the rear do have the same effect... one is easier than the other... but, if you plan to put on lower handlebar mounts and bars, you may be limited in the amount that you can raise the forks through the trees... so, in that case, you'd hve to make adjustment at the rear.
 
accel_is_my_drug said:
won't dropping the forks and raising the rear spring on its perch ( aka what the manual calls "preload") accomplish the same thing?
Click to expand...

Just drop the fork as va_rider recommended for starters and see how you like the handling at that point. While it's true that increasing preload will raise the rear that's is not the function of the preload adjuster. The preload is meant to compensate for the weight placed on the bike, not to just raise the rear. It should be used to properly set the sag of the rear suspension.
 
You start by having the suspension set up for your weight ie proper sag. A lot of your local motorcycle shops should be able to help you with this process for a fee. If you have a few buddies around you could do it your self. Sag will determine the amount of preload required for your weight on the bike and for street riding only change if you gain or lose a significant amount of weight.

If you do not like the results after that then lower the front a little, just remember you will lose some ground clearance. I have a couple of big suspension Mods on my 09. Penske rear shock and 05 R1 forks up front. The rear of my bike is up 5mm over stock and the front about 7.5 to 10mm lower in the front(r1 forks are shorter). I do not have any stability issues with the geometry change but I do have a steering damper set on a light setting.
 
Sliding the fork up 5mm will help but ultimately if you want better feel from the front end you much loose the stock risers and bars. They are rubber mounted and numb. To get better feel a clip-on is really the only way to go. Apex riser clip ons, or ConvertiBars are great options. The other thing they do is place your body in a more sporting position. Once you do that your upper body will be lower relative to the bike. This will put more weight over the front, lower your center of gravity, give you better feel over the bike, and make it easier to ride the bike fast. Finally get rid of the stock rearsets, they're terrible. They are rubber mounted too and total mush. There are a bunch of rearsets that work well, and once mounted they will complement the lower bar nicely.

With the wheelbase as long as the FZ1 is I wouldn't worry about it being unstable, the thing is like a bus.
 
accel_is_my_drug said:
...I wish my 2006 FZ1 felt a bit more like a full on sport bike. I feel like the front end is a tad vague..
Click to expand...

Lots of good advice given so far but don't forget how much tires affect turn-in feel. If they are worn get new. If they are not worn try ones with different profiles. Tire choice can change "feel" a lot.

Dave
 
yeah..
so far I am unimpressed with the bridgestones on the bike right now... they don't seem as sticky as the last pair of dunlops i had on my VFR.

I'm still looking through handle bar options... I kinda liked the speedymoto clip ons... I'll take a look at these apex ones..
 
DMc said:
Lots of good advice given so far but don't forget how much tires affect turn-in feel. If they are worn get new. If they are not worn try ones with different profiles. Tire choice can change "feel" a lot.

Dave
Click to expand...

Very good point Dave. Thanks for bringing us back the the obvious things that we forget about. It's so easy to go mod crazy when the solution is often just getting bike back to what it is supposed to be.
 
Hellgate said:
you must loose the stock risers and bars. They are rubber mounted and numb. To get better feel a clip-on is really the only way to go. Apex riser clip ons, or ConvertiBars are great options.
With the wheelbase as long as the FZ1 is I wouldn't worry about it being unstable, the thing is like a bus.
Click to expand...

I think new risers, or adjustable clip ons are going to be the way to go...

I like the speedymoto riser clip-ons, but damn they are expensive... can't seem to find any used ones either...

Have had no luck finding the SV650 short risers either...

I'll keep on looking and thanks for all the info..
 
accel_is_my_drug said:
I think new risers, or adjustable clip ons are going to be the way to go...

I like the speedymoto riser clip-ons, but damn they are expensive... can't seem to find any used ones either...

Have had no luck finding the SV650 short risers either...

I'll keep on looking and thanks for all the info..
Click to expand...

Remember that the rubber isolators are in the top of the triple clamp. Different risers will get you lower but you'll still have the flex.

By the time you get riser and buy a nice bar you are almost to the cost of clip ons. I'd go the clip on route and be done with it.

One other option is Woodcraft clip ons. They make a 3" tall one. www.woodcraft-cfm.com - 3InchRiserClipon

A free mod you can do is flip the rearset mounting washers around. That will help kill some of the flex from the rearsets. The footpegs are still marshmellows, but it is better. FZ6 and R6S footpegs will fit in place of the FZ1 pegs. Either of these are better options in terms of getting better feel.
 
Hellgate said:
Sliding the fork up 5mm will help but ultimately if you want better feel from the front end you much loose the stock risers and bars. They are rubber mounted and numb. To get better feel a clip-on is really the only way to go. Apex riser clip ons, or ConvertiBars are great options. The other thing they do is place your body in a more sporting position. Once you do that your upper body will be lower relative to the bike. This will put more weight over the front, lower your center of gravity, give you better feel over the bike, and make it easier to ride the bike fast. Finally get rid of the stock rearsets, they're terrible. They are rubber mounted too and total mush. There are a bunch of rearsets that work well, and once mounted they will complement the lower bar nicely.

With the wheelbase as long as the FZ1 is I wouldn't worry about it being unstable, the thing is like a bus.
Click to expand...

Pete, whats the point of making an SS bike out of the FZ1? Rather buy a liter superbike. Ofcourse this will be expensive insurance wise for those who are young or have a crappy driving record. But I am kinda seeing no point in this slowly over the years after modding both the FZ6 and FZ1 to be a bit sporty ergo and performance wise. Buy a literbike, slap on some convertibars and call it a day. That is why I am looking for a daytona 675 later this year. FZ1 will be reserved for commuting and SPORT touring mostly.
 
Because I don't want the rough ride of a sport bike. I like a larger standard bike; larger saddle, longer wheel base, taller, etc. My FZ1 egos are nowhere near an SS bike. If the mounting points of the FZ1 weren't rubber the bike would give better feedback regardless of ego layout. Besides, Convertis on an SS bike can only go so high, just like on the FZ they can only go so low.
 
i have had the forks up through the clamps about 8mm for about 30 seconds, feels horrible and wont turn in, feels like if you spin a bicycle wheel in your hands and try to move the wheel, nasty, i have the rear preload set high number6 i think with 2.5 turns out from hard on the rebound i think..... front 4.5 lines preload, comp 7 clicks and ten 18 clicks both from hard, feels good now but still not amazing, my advise would be leave the forks were they are and jack up the back and see what ya think....
ps. it works for me maybe not you!!!!!!!
 
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