696 fork swap help

[Link]

Good point Raux, the 848's would be a poor choice when lowering the bike. When I was doing the swap I was told by a suspension guy that there are a lot of Japanese bikes that have the same size lower & top tube OD as stock, his thought was there would be no boring/shimming of the triple. I never checked it out as I already had the new forks in hand. So maybe you can get a decent set off a Japanese bike that are closer to the 696 length. I ended up raising the ride height now theres about 44mm of tube above the top triple which puts the adj. nut about 12mm below the bars. I'm using a 60mm bar riser. I could have gone with a lighter spring & more preload but I figured I'll back off on pre load for the GF & a heavier person could ride the bike & not have to re-spring it. I had no clue the 848 forks were longer until I mounted them up !   

[tiger_one]

Welp, jumped into the deep end, so now will have to swim, dog paddle or something.

848 forks on the way, service manual downloaded.  270mm springs, that lets my ex tiger out with 295mm springs 6.0 sigh.  848 travel is 5", 696 is 4.7.  Might could limit the travel to 4" and cut the preload tube/shim for keep the preload adjustment down flush, give me some more room.

I keep thinking there is some dead space in there maybe, cut 2" weld back in a zone that doesn't matter, but the damper rod and weld.  Just thinking outside the tube a bit.

[Link]

So much for taking it slow ! I was thinking the same thing about some dead space in the 848 since the travel is only .3 more & the tubes are over 2 inches longer. But IMO I would try & keep as much travel as possible. I know getting the bike lowered is your main concern so thats a whole another chalange. For what it's worth I think the main reason the GF is more confident on the bike is that She is now using 3/4-7/8 of the 848 5" which is keeping the front wheel planted on the pavement where as the stock forks She would only use about 1/3 of the travel. Good luck with the project & don't forget some pics & results when your done

[Raux]

I have some gold nitride lower tubes from an s4r that are in decent shape i think. everything is already disassembled. springs dampers, etc.
they are definitely shorter than the 696 tubes.

[tiger_one]

A little taller at the front than the rear (in lowering) may not be a bad thing, slow the handling some maybe.

If there is 2" dead space, best would be to cut at top and rethread the end, then shorten the damper rod.  Might need to lower the oil level to give more air gap.

Recut the seat (3rd time) and fits better now for her.  Ordered 66nm spring for shock.

[Link]

Just some info FYI, I was also thinking to have the front a bit taller to accommodate the longer forks but IMO the stock geometry on the 696 works very well & even with the the wide handle bars the bike is not a real quick turner so I wasn't real found of raising the front. From the seating position it appears that the weight bias would favor the front. But I don't think thats the case, I used 2 scales to weigh the bike one under each wheel, with no rider & about 3/4 full tank it weighed 380lbs. 190lbs on the front & 190lbs. on the rear. With a 170 lbs rider the front weight was 260lbs & the rear 290lbs. I'm not sure exactly what those numbers mean when talking weight bias. At best the bias would be 50% front 50% rear which would seem in line with advertised weight bias of other bikes (I'm not even sure thats the correct way to figure out weight bias). I searched & could not find any weight bias numbers for the 696. Anyway with my goal to get more compliance & feel at the front wheel I thought raising the front was a bad idea.     

[Raux]

was the rider in riding position with feet on pegs, etc?

[Link]

 I had 3 guy's, 1 holding the front, 1 holding the rear & the rider in riding position feet on pegs, I had rider pretty much in a neutral position. I was surprised too see so much weight on the rear & I was going to switch scales around, have rider change positions ect.  & try a few more weigh ins but my "help" were 2 20 year kids in a big hurry so the weight check was cut short maybe the numbers will change next time, even a little down pressure from the holders would cause the scales to go up. Anyway do you know how weight bias is done ? Rider on bike or no rider ? It seems with rider on the numbers will change with riding position & a guy carrying a lot of upper body weight could really add to the front by getting over the tank in a tuck as opposed to a some one that carries more weight in lower body. The rider I used was a skinny 6' 1" kid with no real upper body weight no helmet jacket.

[tiger_one]

I used one scale, one wheel at a time, no rider.  Front = 204, Back= 208.  Nearly full tank, stock 696.

I fitted up 48T rear sprocket and new 110 link D.I.D. chain.  Take off a little easier now in 1st, idle is 5 mph.

We made a ride this morning 2up on my Multi.  First of all, after riding the 696 for the last few days, my bike felt like a HEAVY GS PIG, and it only weighs like 480 with the topcase.

[tiger_one]

Proabably should start a new thread, but this being about the forks on the 696 seems good.

I pulled my forks apart yesterday to have a look see.  I have found that the OEM springs are like .56kg/mm - .88kg/mm progressive and uneven in length between the forks.

I found that the left spring is 485mm and the right is 402mm.  The reason I went in was to try an idea.  I have some OEM Tiger 1050 springs, 270mm .6kg/mm.  I cut the 696 springs and ground a flat put a washer (from racetech mod I did on the Tiger) at the bottom of forks and put the cut on that washer, then a washer between the two springs.

Same thing with the right side only different length to make the difference.  I used the straight rate part of the OEM 696 spring and tossed the progressive end.

Ride was really good, I ran over bumps that I had been trying to avoid to keep from getting ejected.  Forks do not bottom or even come close.  I might have some 848 forks for sale in the future!  

My plan, get 30% - 35% sag with the wife on board.  That would be about 38mm.  Raise the forks about 12mm.  These springs are very close to that.  Just waiting on rear spring to test this week.

Pic.  This is left fork, 696 OEM spring on top, Tiger 1050 on bottom.  I cut the spring about 3/8" longer than needed to make the original length.


update:  Static sag = 20mm (probably could use some preload, cut the spring longer by 1/4")
             Rider sag = 35mm  (me @ 185 lbs)  30mm (wife at 135 lbs)  Almost perfect and since I am trying to lower the bike, will not worry about the static sag being on the low side.

[Link]

That's great if you can the stockers to work. So with the frankinsprings how much of the travel are you using & do you still have the same travel length as stock ? The reason I ask is the major problem I had with the stockers was that last 1.5" - 2" of travel even with my 190lbs the forks never bottomed out but it felt like it, the bottom part of the stroke was so harsh the front wheel was all over the place. I thought part springs & part valving problem but it sounds like it's more spring related.   

[tiger_one]

I have slammed on the brakes trying to catch bumps, no bottoming, but handles really good.  I think the original spring has way too much progressive part and if it does not bottom with my frankinsprings (like that name) it never would with the original.

I put a ziptie on last night and rode over an hour all over the hardest/bumpest roads I have around here.  It is 3/4" from bottom, so total of 4" travel from top to that tie.

Got 52mpg by the way, wish my Multi would do that. LOL

P.S.  I got my 848 forks (they are beautiful!), and ordered .85kg/mm springs from RT.  By my measurements they will just fit under my bars (on risers) but not room for anymore preload backing off, thus the lighter springs for her weight should allow me to keep them down more flush.

[Link]

Well it sounds like frankinspring fork works for you but riding that hard & your weight & still having 3/4" left of travel would probably mean a very stiff ride for a 130lb rider. FYI the suspension guy told me is that the stock 848 rebound valving is crap & He always changes that when working on the 848 fork He says the compression valving is fine no need to mess with it. Now for your next mod toss in some Galfer or Braking rotors to really get the front end right ! They make the correct off set so you'll shave 2lbs un sprung weight, save $50.00 in shims & spend $550.00 on the rotors it's a great deal I call it Monster math.

[tiger_one]

I didn't like the way the forks felt/sag.  Pulled them and weighed at 50lbs (+10 for weight of fork leg) and 100lbs, measuring with ziptie the sag.  Left fork was way less than the right.  Pulled the springs and installed 10mm PVC spacer with washer in left leg.  

Much closer to same weights and distance on both fork legs now.

Progress on 848 forks.
Ordered m8 x 25mm buttonhead torx 40 bolts (OEM are 20mm) and finished the spacers and axle bushing.  I messed up one spacer and marginal on another one, so may make another one.


P.S.  You will not find these parts in the catalog. 

[tiger_one]

Update on the frankenspring.  I changed out the oil for 5 wt.  Put 500ml, book calls for 538ml (I only had one liter).  Tried to balance the sag with weight for each fork.  Set left to 65mm sag at 140 lbs (about right for rider and bike). On filling the right, it felt like a hydralic lock and stopped at 35mm.  Drained 125ml, sag now goes to 68mm, figured that is close enough.

Test ride to follow, if this does not get them closer to compliant, 848 forks here we come!