Much "Forking" Better !!

[tizzrr]

After about 6 more outings at the local track,  I am now starting to get faster and am pushing the bike harder through the apexes.  Then that unsetteling feeling of soft / sproingy suspension reared its ugly head !! 

Well, to make a long story slightly shorter, here is what I have as a setup now.

Rear shock is set at maximum preload (Stock shock-150 pound rider)

Front forks-- I have added a spacer of plastic pipe section just under the fork caps.....its about 1.25 inches tall.

With the forks completely compressed and all of the springs and spacers removed, I have added 20 weight fork oil till its 220 mm from the top of the fork tubes for a oil level.  (This is maybe DOUBLE the amount that my local Honda dealer said was stock spec.....which I think 140ml is insanely little or incorrect) 

It now has very good damping, both compression and rebound.  The spring preload is finally about right, about a 1 inch sag when I sit on the bike with my gear on.

It feels like a very different bike on the track now.  Much more forgiving as to throttle changes in mid corner.  Before you had to brace yourself for the on / off throttle front end action !! 
Now, you can roll off or on moderately and the forks dont move very much so it follows a constant arc in the turns.  Much easier to stay on your line under braking too.

I should note, I have raised the fork assemblys about 12mm in the triple clamps also to quicken up the steering a bit also.

Made it a much easier bike to ride fast as Im pushing it harder as I get used to it.  Now im starting to feel the need for better compound brake pads and a nice firm braided brake line. Those are on order now.  That will surely lead to a pair of Michelin Power Pilots soon there after !! 

[clarkdw]

Here is the info on fork capacity from the Honda Service manual. I will add the fork pages in separate posts.

[clarkdw]

The fork parts list and assembly. I know you probably don't need this.

[clarkdw]

The breakdown drawing. HTH if I can dig out any more info from the manual, let me know. I appreciate you sharing your experience with getting the suspension setup. I am looking forward to using some, if not all of the things you are doing.

One question: Do you think that raising the fork tubes would be ok on a street bike? Does it make the bike twitchy?

I just installed Diablo's 110/70 and 150/60 and they really are great tires. The comfort level is very high and so the weaknesses in the suspension become obvious. Oh well, half of the fun of having any performance vehicle is making it better and better.

Clark

[tizzrr]

Thanks very much for posting the info pages !   

My local Honda dealer is so full of crap at times its pathetic !!  He was off in fork oil volumn by about 400% !!!   

As I see by the spec page....if Im reading it right, looks like a fork oil level of around 95mm when everything is compressed with the springs and spacers out is standard.   Hmmm........ I still have a gap of 220mm.  Maybe time to add a little more oil.

I have raised my forks about 15mm in the clamps now from stock.  Its gettin a bit "Pushy" now but by no means twitchy.  Maybe about 12mm would be fine for street use.  Remember to use more preload when raising fork assemblys, because with raised fork assemblys and combined mushy pre compressed forks,
you would have quite a steep steering head angle, and maybe things may get twitchy or headshakey then .

I dont know what good tires are like, as Im running some unknown IRC Winners ?   However I am dragging both footpegs now and no slipping yet.  One of those "Huh" deals.  So once they wear out then comes some proven rubber.  Likely will need to saw the sidestand off then !   

[clarkdw]

Hi tizzrr
My interpretation based on what you said about your fork levels and the way the manual reads is that the 510cc volume is for both forks combined. They have listed left and right below with no number and that usually means that they would get equal portions of the total.

Let me know if this seems right based on the 95mm measurement.

I got new tires because the original tires that came with the bike new were very hard and even though I was getting the bike pretty far over I always felt very uncomfortable. When I raced sportscars I often used old rubber and I found that when the compound goes hard sometimes the tires would give no warning at all before breaking away, something I really did not relish the thought of on a pristine condition bike that I just bought.

Clark

[tizzrr]

Cant say for sure if that 510 is equally divided between left and right legs.  I dont even know how much I have put in, as, I just keep pouring until the level reached the desired spot.  I use a wooden dowel thats marked with a permanent magic marker, like a makeshift dipstick to see where Im at.

Yeah, the sudden release old tire compound issue is allways one to worry about.  Back in the day, I used to run race Michelins that would grip like crazy......till.......FOOOOM !!   No warning before the limit !

Mighty glad 20 years of tire technology have done away with that trait !! 

TIZZRR

[clarkdw]

The one single thing that changed the most between the time that I began racing go-karts and my son started 20 yrs later was the tire technology. The two stroke karts I raced in the seventies had much more horsepower than the four strokes my son started on in the early nineties. The lap times were faster on the later four strokes on the same track even on twenty year old pavement. 

It is a real blesing to be old enough to appreciate how much tire technology has advanced. 

Clark

[homersimpson]

hi, sorry for dragging up and old thread, but im trying to sort out the front end of my bike as described here. the problem im having is getting the top cap screwed back on with the 1 and a 1/4 inch spacers in... it just doesent want to go back together! did you have this problem?
cheers, homer