lowering stock suspension

is there any way to lower the rear? i dont see any adjustments on the stock monoshock, am i missing something? how far can you lower the front without it messing with the steering dynamics?

a question to you is why do you want to lower the rear?

answer to your question is - there is no way to lower the rear the way the bike stands now. stock settings are preload and damping.

the front can be lowered but that depends mainly on how slap happy you want the front to get. this model bike has very neutral steering. if you lower the front by even 5 mm, the steering (turn in) will quicken up but your high speed stability will start to suffer. i am under the assumption that bearings and whatnot for the front and rear are okay, no slop or wear. if not, then these parts will aid in even worse steering feel.

if the bike sags in either the front or the rear, lowering the front will make things bad as well. mainly when you hit a bump and the fork starts to compress or if you are on the brakes the forks start to compress, but your springs are saggy and it gets to the point where you do not have enough front end suspension travel. lowering the forks within the tree (by some max amount) will eventually cause you to bottom out the travel of the fork and quite possibly hit the bottom of the front fairing.

things to think about?

1. how much height do you want to lengthen/shorten to the front and/or rear?

2. what are conditions of my forks? if i am at a standstill with the front brake engaged pushing down hard on the front, does the front pogo, sag quickly but return slowly, or are the forks stiff or hard?

3. what is condition of shock? same as #2.

4. shock can be replaced with some other shock of various length or replace dogbone(s). is this an option for you? do you have time and/or money for either option?

5. is the height that you want to lengthen/shorten worth it?

Here is a lowering "dogbone" that works for the Hurricane:

http://www.jcwhitney.com/autoparts/Product/tf-VehicleBrowse/s-10101/Pr-p_Product.CATENTRY_ID:2009753/showCustom-1/p-2009753/N-111+1990+200730430/c-10111

i was going to lower both the front and the rear by about 3/4 inch, to and inch, the bearings are good. the forks are good, with the brakes on and pushing down hard it goes down then comes back up a couple inches and stops till i let off of it. (im also a pretty big guy 260lbs, i should get a bigger bike but i got this one for a deal) as far as the travel goes i want to put it at a safe hight that wont bottom out the fairings if i ever get them back on, but leave enough clearance to get over speedbumps and shit like that. the rear shock is good stiff but good.

quite honestly, if i were you i would not lower the bike unless you have a short inseam.

at 260lbs, you probably have the bike squatting quite a few millimeters. if you lower it an inch at the front, when you go to brake, you'll be transferring a lot of the weight onto the front suspension. my take on it is you are going to lose some much needed suspension travel if you knock out an inch. i give up a 100lbs to you and if i knock out an inch, i come very close to the bottom of the front fairing if i brake hard. i'm gonna go out on a limb and say if you do the same thing, your front fender is going to touch your front fairing.

have you tried preloading the shock?

another question to you - why do you think that it is not at a safe height now?

you can experiment with getting a new dogbone, but i don't think it is worth $140. i do not know what increments the rear will be lowered if you get a new dogbone.

usually if the fronts are lowered, preload would be adjusted accordingly to stiffen up the forks to compensate for the lose of travel. but these forks have no adjustment. only way to stiffen up the front is to change to heavier springs.

inseam?

i dont have any plasics on exept for the tail section and the upper fairing and im pretty sure thats all im gonna run with.

preloading the back shock? how do you do that?

the height isnt unsafe but i have ridden lower bikes and i like the way they feel. i was asking for a safe height that wont bottom out, and catch my pipes.

i have been riding for years but not with my own bike this is my first "crotch rocket" style bike that i own. im kinda pressed for cash right now so i dont think im gonna be trying out the dogbone any time soon.

what psi do you run in your front shocks? mine is at 4 now i cant feel the diffrence between 4-6 so i dont bother putting in the extra.

inseam... as in pants.. that other number along with waist size. are you a tall guy or short guy or do you have long or short legs. if you are short then i can see your wanting to lower the bike some.

preloading the shock is merely adding in more spring compression by turning the adjustment ring under the spring. you'll see it in the picture. you will need a preload adjustment tool, basically a hook to pull the collar. it can be bought at any motorcycle shop for around $10 if your bike didn't come with the factory tool kit.

adjust the collar as necessary until when you sit on the bike, the back does not sag but a few mm.

i don't really think that there is a "safe height" for a bike. i would assume that it is safe the way it is designed and made.

i run 0 psi up front. as you ride, the fork action will cause the air that is in the fork to expand. also heat from the air and engine will be absorbed some by the forks. i've never really found that air at any psi in the forks made any difference. i run stiff fork springs.




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im 6ft but i have short legs all i really want to do is be able to put both my feet completly on the ground at the same time.

i have to go to a shop and pick up one of them tools, how hard is it to change fork springs? how much do they run?

i wouldn't worry about putting both feet completely on the ground as on most sportbikes most people can't. most of the time you'll have one foot completely on the ground and the other one you'll have the toes and the ball of your foot on the ground.
don't worry about not having both feet on the ground, you'll get used to it.

i'm not sure how hard it is to change the springs as i have never done it myself. you may want to ask you local motorcycle mechanic or accessory shop that question and what tools you will need. i don't think it is that hard, but like i said before.

take alook at this link:
http://www.ronayers.com/fiche/200_0287/front_fork/front_fork.cfm?man=ho&groupid=5100&parent=5070

it has a fork schematic. doesn't look to difficult.

as for springs. a pair will run around $120 give or take a few dollars. if you decide to change your springs, get a set in the range your weight is in.

ok i wasnt sure if i was the only one

thanks for the help man

im only 5'5" with short legs. i can bounce my back left to right and right to left with nothing more than my toes on the ground. onc eyou find your balance it is cake. i typically have my right foot on the peg and brake, while my left foot sits flat footed as i lean the bike over. depends on if im on a hill, crap road, or whatever.

Can you raise the rear by adjusting the spring with the preload adjustment tool?

no.

the rear suspension is fixed. that means it is bolted at 2 points and that distance when the shock is unloaded will always remain the same unless the shock is compressed.

the adjustment of the spring is only related to making the suspension loose or stiff. there is no height adjustment relative to this change. height adjustment can only be made through overall length of the shock or changing certain rear suspension items such as the dogbone or relocating the top shock mount.

87-90 cbr's do not have a clevis mount. so overall height adjustment cannot be made using shims or washers. another way would be to get an aftermarket shock with height adjustment. most aftermarket dogbones i've seen usually lower the rear, not raise it.

i have an idea of how i could make the rear height adjustable but i still need to test out this theory. this is more or less an outstanding issue i've been trying to resolve for the last several months for the use of a f3 swingarm conversion.