Front End Choices ?

[jo1000]

I changed the rear shock ( Penske 8983) I had built for me at Traxxion, it works great, the bike feels nice and planted. Now I was wondering about the front end , it does have a stiff feel to it. Dare I say cheap feel to it. I would love to hear about some front end mods here ,I'm not sure I want to go the AK20 Route.. Maybe some members here have some options I don't know about ...

[bobdog]

joyrider, get in touch with pattonme! 

[timg]

joyrider, get in touch with pattonme! 

http://fj-09.org/thread/2576/product-offering has some info 

[bruceintucson]

I changed the rear shock ( Penske 8983) I had built for me at Traxxion, it works great, the bike feels nice and planted. Now I was wondering about the front end , it does have a stiff feel to it. Dare I say cheap feel to it. I would love to hear about some front end mods here ,I'm not sure I want to go the AK20 Route.. Maybe some members here have some options I don't know about ...

Discussed this several times and if you weigh under 180 or so this mod costs about $10. Take the right fork leg off (loosen the top nut first...careful of the ABS sensor & ABS disc on the wheel). Unscrew cap and pour out somewhere between 220-250 cc's of the 5 wt fork oil (a Ratio-rite works perfect for this). Replace with the exact amount you removed with 2.5 wt oil. Snug the cap, slide the right fork back into the triples and snug it with the lower triple pinch bolt. This is a great time to raise the forks to put more weight on the front end. 5-6mm is a good compromise; use a business card with a marking on it so you can get both forks the exact height. Loosen the left top triple pinch bolt & spin the cap out til it's free. Add 15cc of fork oil to each fork leg (you can get a small graduated medicine device used for giving medicine to children for free at Walgreens/CVS, etc.)Tighten each fork cap, tighten the upper & lower pinch bolts (19 ft/lb upper, 17 ft/lb lower), slide fender into place but don't tighten bolts yet, install front wheel & torque axle but not pinch bolt, install brake calipers & torque to spec; install ABS sensor & cover. Put weight back on front wheel & bounce the front end up & down a few times using handlebars but DON'T apply the front brake. Tighten axle pinch bolt 17 ft/lb, tighten fender mounting bolts. Add 1-3 clicks of rebound and go ride. The lighter oil reduces the cheap/overly aggressive compression valving and the 15cc of oil added per for leg greatly reduces dive under braking without affecting overall ride quality. There is plenty of rebound, you don't have to worry. You could probably replace all 450+cc's of 5 wt in the right fork with 2.5 wt and still have plenty of rebound.Check your steering head bearing preload while the front wheel's off the ground. It should fall easily to either side with no drag or binding felt. Most appear to be coming from Yamaha over-tightened which drastically effects handling in a negative way! 

[xlxr]

If you are a big guy like me, start with heavier spring. Then I went with Ohlins, with compression fork revalved by Norwest Suspension.

[jo1000]

I changed the rear shock ( Penske 8983) I had built for me at Traxxion, it works great, the bike feels nice and planted. Now I was wondering about the front end , it does have a stiff feel to it. Dare I say cheap feel to it. I would love to hear about some front end mods here ,I'm not sure I want to go the AK20 Route.. Maybe some members here have some options I don't know about ...

Discussed this several times and if you weigh under 180 or so this mod costs about $10. Take the right fork leg off (loosen the top nut first...careful of the ABS sensor & ABS disc on the wheel). Unscrew cap and pour out somewhere between 220-250 cc's of the 5 wt fork oil (a Ratio-rite works perfect for this). Replace with the exact amount you removed with 2.5 wt oil. Snug the cap, slide the right fork back into the triples and snug it with the lower triple pinch bolt. This is a great time to raise the forks to put more weight on the front end. 5-6mm is a good compromise; use a business card with a marking on it so you can get both forks the exact height. Loosen the left top triple pinch bolt & spin the cap out til it's free. Add 15cc of fork oil to each fork leg (you can get a small graduated medicine device used for giving medicine to children for free at Walgreens/CVS, etc.)Tighten each fork cap, tighten the upper & lower pinch bolts (19 ft/lb upper, 17 ft/lb lower), slide fender into place but don't tighten bolts yet, install front wheel & torque axle but not pinch bolt, install brake calipers & torque to spec; install ABS sensor & cover. Put weight back on front wheel & bounce the front end up & down a few times using handlebars but DON'T apply the front brake. Tighten axle pinch bolt 17 ft/lb, tighten fender mounting bolts. Add 1-3 clicks of rebound and go ride. The lighter oil reduces the cheap/overly aggressive compression valving and the 15cc of oil added per for leg greatly reduces dive under braking without affecting overall ride quality. There is plenty of rebound, you don't have to worry. You could probably replace all 450+cc's of 5 wt in the right fork with 2.5 wt and still have plenty of rebound.Check your steering head bearing preload while the front wheel's off the ground. It should fall easily to either side with no drag or binding felt. Most appear to be coming from Yamaha over-tightened which drastically effects handling in a negative way!

Thanks Bruce but I weighted 180 in high school , those days are over. 

[clint]

I changed the rear shock ( Penske 8983) I had built for me at Traxxion, it works great, the bike feels nice and planted. Now I was wondering about the front end , it does have a stiff feel to it. Dare I say cheap feel to it. I would love to hear about some front end mods here ,I'm not sure I want to go the AK20 Route.. Maybe some members here have some options I don't know about ...

Discussed this several times and if you weigh under 180 or so this mod costs about $10. Take the right fork leg off (loosen the top nut first...careful of the ABS sensor & ABS disc on the wheel). Unscrew cap and pour out somewhere between 220-250 cc's of the 5 wt fork oil (a Ratio-rite works perfect for this). Replace with the exact amount you removed with 2.5 wt oil. Snug the cap, slide the right fork back into the triples and snug it with the lower triple pinch bolt. This is a great time to raise the forks to put more weight on the front end. 5-6mm is a good compromise; use a business card with a marking on it so you can get both forks the exact height. Loosen the left top triple pinch bolt & spin the cap out til it's free. Add 15cc of fork oil to each fork leg (you can get a small graduated medicine device used for giving medicine to children for free at Walgreens/CVS, etc.)Tighten each fork cap, tighten the upper & lower pinch bolts (19 ft/lb upper, 17 ft/lb lower), slide fender into place but don't tighten bolts yet, install front wheel & torque axle but not pinch bolt, install brake calipers & torque to spec; install ABS sensor & cover. Put weight back on front wheel & bounce the front end up & down a few times using handlebars but DON'T apply the front brake. Tighten axle pinch bolt 17 ft/lb, tighten fender mounting bolts. Add 1-3 clicks of rebound and go ride. The lighter oil reduces the cheap/overly aggressive compression valving and the 15cc of oil added per for leg greatly reduces dive under braking without affecting overall ride quality. There is plenty of rebound, you don't have to worry. You could probably replace all 450+cc's of 5 wt in the right fork with 2.5 wt and still have plenty of rebound.Check your steering head bearing preload while the front wheel's off the ground. It should fall easily to either side with no drag or binding felt. Most appear to be coming from Yamaha over-tightened which drastically effects handling in a negative way!

Bruce, do you think it would be possible to extract the 5wt fork oil out of the right leg using a syringe with plastic tubing extending down into the fork leg? At 175lb, this might be an inexpensive solution for me. 
Also, is the additional 15cc of oil added to both forks 2.5wt?

[bruceintucson]

Good possibility but you'll have to compress the fork so you can get access to the oil (which means the front wheel/fender will have to be removed and it will be a tight fit fir the tubing with the spacer & spring in place; might as well just remove the fork). You'll have all that stock 5wt left over removed from the right fork leg so you can use it, though at only 15 cc's per leg don't think it really matters. Really makes a noticeable difference on ride compliance and brake dive.

Bruce, do you think it would be possible to extract the 5wt fork oil out of the right leg using a syringe with plastic tubing extending down into the fork leg? At 175lb, this might be an inexpensive solution for me. 
Also, is the additional 15cc of oil added to both forks 2.5wt?

 

[clint]

Bruce, do you think it would be possible to extract the 5wt fork oil out of the right leg using a syringe with plastic tubing extending down into the fork leg? At 175lb, this might be an inexpensive solution for me. 
Also, is the additional 15cc of oil added to both forks 2.5wt?

 
Thanks for taking the time to respond and write this up Bruce!

[pattonme]

> between 220-250 cc's of the 5 wt fork oil ... Replace with the exact amount you removed with 2.5 wt oil.
 
Here's a handy chart of oil viscosity options. I would pick from the 8-11cSt@40 range. Yes the 3W shock oil works fine.
Playing with oil is only a band-aid though so don't expect miracles. But if it's good enough for your needs...
 
https://dl.dropboxusercontent.com/u/180639/Forks-by-Matt/Fork%20oil%20weights.html
 
The left leg does absolutely nothing so unless you're changing out the spring I'd leave it alone and not worry about adding more fluid either. And yes you can fish a hose down the fork and use something like a MightyVac brake bleeder to suck fluid out of the fork and then pour the balance back in.

[bruceintucson]

 
 

> between 220-250 cc's of the 5 wt fork oil ... Replace with the exact amount you removed with 2.5 wt oil. The left leg does absolutely nothing so unless you're changing out the spring I'd leave it alone and not worry about adding more fluid either. And yes you can fish a hose down the fork and use something like a MightyVac brake bleeder to suck fluid out of the fork and then pour the balance back in.

 

[bruceintucson]

 

> between 220-250 cc's of the 5 wt fork oil ... Replace with the exact amount you removed with 2.5 wt oil. The left leg does absolutely nothing so unless you're changing out the spring I'd leave it alone and not worry about adding more fluid either. And yes you can fish a hose down the fork and use something like a MightyVac brake bleeder to suck fluid out of the fork and then pour the balance back in.

 

[bruceintucson]

Sorry for all the "nothing new" fork posts, don't know what I'm doing wrong. Yes swapping fork oil viscosity is a band aid, but actually works quite well. And the reason for adding 15cc of oil to the left leg (as well as the right leg) is to keep the air gap the same in both forks. Generally a good idea. 

[clint]

Discussed this several times and if you weigh under 180 or so this mod costs about $10. Take the right fork leg off (loosen the top nut first...careful of the ABS sensor & ABS disc on the wheel). Unscrew cap and pour out somewhere between 220-250 cc's of the 5 wt fork oil (a Ratio-rite works perfect for this). Replace with the exact amount you removed with 2.5 wt oil. Snug the cap, slide the right fork back into the triples and snug it with the lower triple pinch bolt. This is a great time to raise the forks to put more weight on the front end. 5-6mm is a good compromise; use a business card with a marking on it so you can get both forks the exact height. Loosen the left top triple pinch bolt & spin the cap out til it's free. Add 15cc of fork oil to each fork leg (you can get a small graduated medicine device used for giving medicine to children for free at Walgreens/CVS, etc.)Tighten each fork cap, tighten the upper & lower pinch bolts (19 ft/lb upper, 17 ft/lb lower), slide fender into place but don't tighten bolts yet, install front wheel & torque axle but not pinch bolt, install brake calipers & torque to spec; install ABS sensor & cover. Put weight back on front wheel & bounce the front end up & down a few times using handlebars but DON'T apply the front brake. Tighten axle pinch bolt 17 ft/lb, tighten fender mounting bolts. Add 1-3 clicks of rebound and go ride. The lighter oil reduces the cheap/overly aggressive compression valving and the 15cc of oil added per for leg greatly reduces dive under braking without affecting overall ride quality. There is plenty of rebound, you don't have to worry. You could probably replace all 450+cc's of 5 wt in the right fork with 2.5 wt and still have plenty of rebound.Check your steering head bearing preload while the front wheel's off the ground. It should fall easily to either side with no drag or binding felt. Most appear to be coming from Yamaha over-tightened which drastically effects handling in a negative way!

I got around to making this change yesterday and went riding today. MUCH BETTER! The compression is much more compliant now! No more harshness! There is still significant dive on braking, so I don't see much change there, but for the 2 hrs of work and $10, this is a significant improvment. Thanks Bruce!

[xlxr]

It may be possible to do this without removing forks from bike, but it is easier to take the forks off, and you may save scratching your bike or spilling oil all over it. Taking the forks off and pumping them, and turning them upside down and back and forth is needed to get all the oil out. I assume 220 -250 cc's is all the oil. In addition, after adding oil, the next thing to do is pump the forks a lot to get out all the air and measure oil height to verify it is correct, which means the forks need to be held vertically. Turning the forks upside down and letting them drain will help get out a lot of the sludge at the bottom. If I am not taking the forks apart, I will pour a little oil in the bottom and re-drain it just to clean the sludge out of the bottom.