fork possition?


12 replies to this topic
  • razornpc

Posted July 17, 2007 - 11:54 AM

#1

what will it do if i raise or lower my forks?

  • grayracer513

Posted July 17, 2007 - 01:00 PM

#2

It changes the steering head angle (rake) and can alter the way the bike behaves in corners a little. Raising them generally makes the bike more willing to turn in without pushing the front end as much, but it may have an adverse effect on the bike's stability in a straight line.

  • ben_suhard

Posted July 18, 2007 - 09:08 PM

#3

what will it do if i raise or lower my forks?

I'll explain a bit further. Dropping the forks through the clamps will increase rake and trail, making the steering behave more like a shopping cart wheel, more self steering which is better for high speeds. It also lengthens the wheel base for more stability. Raising the forks through the clamps makes the steering more direct, which will give you more(quicker) steering control, good for lower speeds, but the bike will be more likely to experience head-shake(the bars turn side to side violently) when hitting bumps at speed. The shorter wheelbase also helps with tight cornering.
There's a picture on this page to help you see what happens and explains some more: http://www.cycleimpr..._pages/022.html

  • bjn

Posted July 19, 2007 - 06:51 PM

#4

Will a stabilizer help with the stability and shake, allowing fork adjustments to achieve quicker handling without the instability at higher speeds?

  • ben_suhard

Posted July 19, 2007 - 08:48 PM

#5

Will a stabilizer help with the stability and shake, allowing fork adjustments to achieve quicker handling without the instability at higher speeds?

Yep, a damper helps a lot.

  • razornpc

Posted July 20, 2007 - 09:01 PM

#6

ok that makes sence, so why when im jumping does the back end kick out?? im just starting to feel comfortable hitting bigger jumps and noticed that the harder i hit the jump the more the back wants to kick out.

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • grayracer513

Posted July 20, 2007 - 09:36 PM

#7

One or both of two reasons:

Any hard edged object the back of the bike runs over will kick the rear of a 4-stroke if you hit it with the throttle off. So if you're rolling over jumps with sharp cut lips or kickers, you'll need to learn to lead the throttle a little more as you clear the launch.

The other is that your rear shock is not able to respond correctly to the impact at the lip of the launch. This might happen because of too much compression resistance, or because it came close to "G-out" bottoming on the jump face, and didn't rebound quickly enough. It might also be that it's rebounding too hard, but that's probably the least likely cause.

  • razornpc

Posted July 20, 2007 - 09:41 PM

#8

well i do give it throttle when im going off the lip, is that why, like is the gyro effect making it wanna move forward or off to the side. how would i be able to check if its bottoming on the face, i think its all stock suspension but i dont think ive ever bottomed out, or i have and i just dont know it.

  • ben_suhard

Posted July 20, 2007 - 09:56 PM

#9

ok that makes sence, so why when im jumping does the back end kick out?? im just starting to feel comfortable hitting bigger jumps and noticed that the harder i hit the jump the more the back wants to kick out.

Do you mean "kick out sideways" or "kick upwards"? When you hit a jump hard enough to compress the rear end, it'll do whatever the jump face tells it to do. It can kick sideways if there's ruts or bumps on the jump face or if the jump's on a corner, and you just have to learn to keep the bike straight by moving your body around, by turning the bars, and try to hit the jump at a better angle or whatever. When you hit a jump hard and the rear end bottoms out, it also compresses the tyre and combined with the spring rebound, the rear end is going to bounce off the jump unless you keep it compressed by throttling on. It just takes practice to learn how much you need to throttle on up the jump face to keep the front end up, because when you throttle off in the air, the rear end will lift. Revving the bike while you're in the air will lower the rear end a bit too, it's commonly called a "panic rev" but it's really an "adjusting rev".

  • ben_suhard

Posted July 20, 2007 - 10:09 PM

#10

how would i be able to check if its bottoming on the face, i think its all stock suspension but i dont think ive ever bottomed out, or i have and i just dont know it.

It's likely that the rear end is bottoming and is perfectly normal even with the correct suspension setup. Do you have any Supercross DVD's? If so, watch the Pros doing jumps in slow-mo to see how often they bottom out the suspension, and they use a stiff setup too. If you really want to check if the rear end is bottoming, you can cut and tie a rubber band around the shock shaft to see if the shock body pushes it down to the bumper.

  • grayracer513

Posted July 20, 2007 - 10:09 PM

#11

how would i be able to check if its bottoming on the face,

Have someone video tape the jump, and play it back frame by frame.

  • razornpc

Posted July 23, 2007 - 01:06 PM

#12

well after this weekend i know for sure that i can bottom out. so ill be respringing i guess.

  • Ga426owner

Posted July 23, 2007 - 01:20 PM

#13

well after this weekend i know for sure that i can bottom out. so ill be respringing i guess.



anyone can bottom out...what is your weight?





Related Content

Forums
Photo

Megabomb Fitment by 288yz450


Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • 1 reply
Forums
Photo

Michigan Motocross Tires by 288yz450


Dirt Bike   Dirt Bike Regional Discussion   North
  • 1 reply
Reviews

Yamaha YZ450F 2017 by Chris.GVS


Yamaha YZ450F 2017
  • - - - - -
  • 0 reviews
Forums
Photo

2016 YZ450 by CaptainKnobby


Dirt Bike   Dirt Bike Technical Forums   Suspension
  • Hot  59 replies
Forums
Photo

The "going back to the other darkside" adventure... by Monk


Dirt Bike   Make / Model Specific   KTM   250/350/450/505 SX-F & XC-F (4-Strokes)
  • Hot  94 replies
 
x

Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.