Looking for some wisdom from you guys....
Done 500mls over 2 days on my gsx, then put it in the garage for 3 weeks. Pulled it out this week to use for work and the front forks are solid. Ive screwed every adjustment out and back iin, everything moving freely. There's 0 sag and if i pull the front brake on, push the front down i can only get 25mm of travel.
Any ideas whats happened ? And how to sort lol
Im sure
@seth had a similar issue - so may be worth a shot at searching his posts
Perfect 👌
Found the post and sounds like the same thing. 500ml trip then all has went solid.
Not sure im capable of stripping it down myself tho 😬
From memory of Seth talking about it you might not need to strip them right down. Just crack the top yoke pinch bolt off & unscrew the caps in the top of the forks. I'm sure Seth said he did that & loads of compressed air came out.
Makes sense. :hat:
That would mean fork seals are shagged (a technical term).
Hiya it was emma's bike had a strange fork seal in it that only had a single seal rather than the more common double seal .
Anyway the problem was it was letting air in on the up stroke and compressing it on the down stroke making the forks become quiet highly pressurised.
That gave 10mm of fork travel .
A new set of seals,bushes and oil now as good as new and a few this and miles later all still good.
@seth did it happen slowly or was it a sudden change ?
Ive had the bike a few years, bought it from my brother and never had any real problems with the suspension. Was using it regularly and my last trip was to Gairloch a 500mls rnd trip and everything was fine. Just when i went to use it this week its solid, no leaks from the seals either.
It came on very quickly .
We think it happened going over a very bumpy field at a rally in Belgium.
Was almost unrideable by the time we got back to Scotland.
Emma made it then I fixed it all .
I'll pop the top off the forks and see if there's anything blatantly obvious. I'd order up seal kits & give it a go myself but i dont have the "special" tool for going down inside the fork legs. Easy enough to make one ?
On early models k2-k4 piece of 1/2" black pipe works great. 70cm is more than enough.
@gmars70970 if you can get up to my place then you can borrow the fork tool I have - its fairy easy job to do but - if you want your welcome to do at my place I have all the tools needed
Del
Quote from: Del on Saturday, 17 July 2021, 06:29 PM
@gmars70970 if you can get up to my place then you can borrow the fork tool I have - its fairy easy job to do but - if you want your welcome to do at my place I have all the tools needed
Del
Thanks very much Del 👌
I popped the top off the forks today. Exactly as
@seth described there was a release of air pressure !
I was going to put it in to the local mechanic but i think i'll give it a go myself, is it overly technical or diy friendly, now i see what the tool looks like im thinking its nothing to fancy.
I actually work at Rolls-Royce Del so im up in Glasgow dailly,might take you up on borrowing your tool.
I have tgese already, would i need anything else other than oil ?
Cheers everyone 👌
I also have this unopened bottle of fork oil i'd bought for my trackbike, 10w be ok for the GSX ?
If its teh RR on Manor Avenue then were not too far apart
Its fairly easy mate- just organise yourself - I do one fork at a time and lay all the pieces out on a towel as I remove (best to clean parts as you remove as old fork oil really stinks) - I use a tub of brake cleaner or thinners to dunk the parts in and wipe down
top tip is to loosen the top yoke mount then undo the top fork bolt but you have already done this so shouldnt be a bother (there a pain in the arse to loosen off the bike)
Let me know if you want loan of the fork tool
Del
Stripped down, now to bodge a tool for re-build.
Its RR aviation at Inchinnan, everywhere north of Ayrshire is Glasgow to us country boys 🤣
Not sure if this a common known fact or ive just found an easy fork tool.
B&Q sell 16mm square bar with 1.5mm wall thickness, the 16mm external fits perfectly in the fork section and the 13mm internal fits a 1/2 socket drive for tightening.
Without scrolling back to check, those look like early K2-K4 forks?
Yip 👌
2001 bike
Just thought I'd mention it as your tool won't fit K5 onwards bikes.
Aaahhhh 👍
For the early forks
Remember you'll need to pump the fork internals as you rebuild them to make sure the oil level is correct when refilling them .
Thanks to the info & advice on here my forks are all serviced and I'm comfortable doing the job myself now.
Few tweaks to do to get them just right but happy with them so far.
Tyre pressure - 36psi
Preload - 2 rings showing
Rebound - 7 clicks from hard
Compression - 4 clicks from hard
Sag - 32mm
Thanks again everyone
Quote from: gmars70970 on Wednesday, 21 July 2021, 09:15 AM
Thanks to the info & advice on here my forks are all serviced and I'm comfortable doing the job myself now.
Few tweaks to do to get them just right but happy with them so far.
Tyre pressure - 36psi
Preload - 2 rings showing
Rebound - 7 clicks from hard
Compression - 4 clicks from hard
Sag - 32mm
Thanks again everyone
Front and rear SAG is 32mm?
Important thing - what free SAG do you have ?
@KoZi just done some more checks.
With me on the bike front sag is 33mm & rear is 21mm .
Think i'll decrease the front a bit to 25-30mm.
Strange thing is the sag when the bikes sitting in the free state.
Front is 31mm
Rear is 2mm ..... yes 2mm
Any suggestions
Quote from: gmars70970 on Friday, 23 July 2021, 09:48 PM
@KoZi just done some more checks.
With me on the bike front sag is 33mm & rear is 21mm .
Think i'll decrease the front a bit to 25-30mm.
Strange thing is the sag when the bikes sitting in the free state.
Front is 31mm
Rear is 2mm ..... yes 2mm
Any suggestions
So you are pinging out from seat when you are hitting a bump... Not good.
As I always say to everyone - 35-45 mm rider SAG (front and rear) is best to set up on first line. Then you are watching your style of riding and you can set to 30 mm if your style is verry agressive, but 30 is limit for the street - checked on many bikes.
Free sag should be 15-25mm front and 5-15mm rear. If you have 2 m is way to stiff - change preload by turn anticlockwise then measure once again. When you also change free sag your rider sag also will go upper in mm - and this is good.
For me in your case - front is little too soft and rear is way to stiff.
Second time - make an videos about rebound and compression - it is also very important.
What Kozi says. Rear end way too stiff. From memory my front rider sag is 30mm, Wilbers progressive springs, works perfectly. Rear i cant remember numbers but setting 2 i think solo. 3 for pillion, also good. Both ends seem to work together. I reckon a lot of recommended settings are way to hard. Good for race track only. IMO.
Just seen your posts
@KoZi &
@grog 👍
I was out a decent run today, Glasgow, Loch Lomond, Glencoe, Fort William, Mallaig, ferry to Skye, onto Plockton, Kyle of Lochalsh and home.... 394mls.
I'd wound the compression back 2 clicks on the front when i was out today and the front feels good. I'll check sag tmrw tho.
100% agree the rear is too hard, i'll adjust that tmrw and increase the sag.
Rear currently showing :
4 rings
No 3 on both rebound & compression.
Quote from: gmars70970 on Tuesday, 27 July 2021, 04:51 AM
Just seen your posts @KoZi & @grog 👍
I was out a decent run today, Glasgow, Loch Lomond, Glencoe, Fort William, Mallaig, ferry to Skye, onto Plockton, Kyle of Lochalsh and home.... 394mls.
I'd wound the compression back 2 clicks on the front when i was out today and the front feels good. I'll check sag tmrw tho.
100% agree the rear is too hard, i'll adjust that tmrw and increase the sag.
Rear currently showing :
4 rings
No 3 on both rebound & compression.
Front: need movie about how forks works.
Rear: Silver springs in earlier models are stifer than red ones. If you have 4 rings out go to 3. It will be better with luggage but without and solo riding you have to go little uper - 2,5 maybe 2. This is all only talking. Measure everything and tell us what are results. :onya:
@KoZi @grog i've spent the day taking measurements.
Front is now showing :
1.5 rings
30mm sag (just the bike)
40mm sag (me & bike)
Rear:
On Ring No 1
10mm sag (just the bike)
32mm sag (me & bike)
I've not taken it out a run yet but hoping thats a good base to work from, does feel soft in the garage, but im comparing it to the gsx when it was solid and my zx6 track bike.
Quote from: gmars70970 on Friday, 30 July 2021, 02:04 AM
@KoZi @grog i've spent the day taking measurements.
Front is now showing :
1.5 rings
30mm sag (just the bike)
40mm sag (me & bike)
Rear:
On Ring No 1
10mm sag (just the bike)
32mm sag (me & bike)
I've not taken it out a run yet but hoping thats a good base to work from, does feel soft in the garage, but im comparing it to the gsx when it was solid and my zx6 track bike.
So in my eyes:
It is better BUT. Ideal base to start is always flat bike. You have a little diferences but not tragic.
Front is little to soft still BUT do you know what springs do you have ? This is important because if you have very high progressive springs when you will increase preload the changes will be cosmetic (inversely as on the linear springs) - go for 1 ring or 0,5.
Rear is good ! - whan compression and rebound numbers ? And important also - do the shocks were servised ? If not the oil in them is... "drama" and I recommended to serviced them.
Ive still to take it a test ride but i've left the front at the setting i had on my last run out.
Tyre pressure - 38psi
Rebound - 7 clicks from hard
Compression - 6 clicks from hard
Front is filled with 10w oil rather than 5w oil, but no idea on the springs, I'd imagine its standard. I bought the bike 2yrs ago with 16,000 miles on it.
Rear is set at No 2 on both settings but not tried it on the road yet.
Quote from: gmars70970 on Saturday, 31 July 2021, 06:04 AM
Ive still to take it a test ride but i've left the front at the setting i had on my last run out.
Tyre pressure - 38psi
Rebound - 7 clicks from hard
Compression - 6 clicks from hard
Front is filled with 10w oil rather than 5w oil, but no idea on the springs, I'd imagine its standard. I bought the bike 2yrs ago with 16,000 miles on it.
Rear is set at No 2 on both settings but not tried it on the road yet.
Sounds similar to my settings, although my standard forks (I.e. assuming linear springs) are now running 5W oil after a full rebuild.
I've got the rears set on 2 at the bottom and 3 at the top and this seems ok for me, preload 3 rings showing.
I would be interested to know how you go with your settings. Mine I did on a road run, I still need to write them down
Not at all an expert, far from. Ive found since Wilbers progressive springs fitted in forks, settings very soft, much improved ride, still very controlled. Major improvement over stock. Best thing was no diving under brakes, between gear changes etc. I think 7.5 is my fork oil. I was offered Race Tech internal valve adjusters at time, was a lot of money, never bothered. Probably best mod ive done along with service on standard shocks at same time. I run them lightly also, bike now works perfectly between fr and rear, feels like an old perfectly set up Ducati. some will know what i mean.
Rattles, clanks & bits fall off?
Quote from: grog on Saturday, 31 July 2021, 07:04 PM
Not at all an expert, far from. Ive found since Wilbers progressive springs fitted in forks, settings very soft, much improved ride, still very controlled. Major improvement over stock. Best thing was no diving under brakes, between gear changes etc. I think 7.5 is my fork oil. I was offered Race Tech internal valve adjusters at time, was a lot of money, never bothered. Probably best mod ive done along with service on standard shocks at same time. I run them lightly also, bike now works perfectly between fr and rear, feels like an old perfectly set up Ducati. some will know what i mean.
I've already bought Race Tech gold kit - waiting to put them on.
UMMMM sorry if this sounds stupid, however when you are winding out it makes the opening larger and allows flow of oil more quickly so it's softer and winding inwards makes it restrict and causes firmer rate. My suggestion is open everything to maximum and take it for a ride. Make notes of the settings and what the bike feels like. Make adjustments back inwards and repeat. If you can ride the same road for your test as a comparison good. :hat: :hat:
Thats my plan now
@GSXKING Had it out a spin today and feels ok, but when pushing on a wee bit the back felt soft. So i'll give it a wee tweak and give it a run tmrw again on the same road 👍
Quote from: KoZi on Monday, 02 August 2021, 01:22 AM
Quote from: grog on Saturday, 31 July 2021, 07:04 PM
Not at all an expert, far from. Ive found since Wilbers progressive springs fitted in forks, settings very soft, much improved ride, still very controlled. Major improvement over stock. Best thing was no diving under brakes, between gear changes etc. I think 7.5 is my fork oil. I was offered Race Tech internal valve adjusters at time, was a lot of money, never bothered. Probably best mod ive done along with service on standard shocks at same time. I run them lightly also, bike now works perfectly between fr and rear, feels like an old perfectly set up Ducati. some will know what i mean.
I've already bought Race Tech gold kit - waiting to put them on.
Of course you have Kozi :notworthy: :notworthy: :notworthy:
What do "Race Tech internal valve adjusters" actually do?
Racetech gold valves
Racetech G3-LD Gold valves;
There is a limitation with re-valving as we are limited to the parameters of the stock piston design. By replacing the stock piston with a Gold Valve we can now exceed those limitations and extend our tuning capability. When it comes to manipulating oil flow, piston design is key. The very force that shim stacks will experience is determined by the dimension of the piston port area.
Larger ports are desirable where less progression is required. Smaller ports for more progression. Progression is a word whose sound is better than its meaning. We all like the sound but in fact, we can get too much of a good thing. To "progress" simply means to transition from one state to another. In suspension terms, we transition from soft to hard. If damping is too progressive we will experience a lack of initial control followed by extreme harshness......very soft to very hard.
The valve allows maximum tunability leading naturally to maximum performance. This is very exciting for Alltech suspension the ability to solve so many problems with so few limitations.
For Motocross, Offroad, Trial, Hillclimb, Supermoto, Street, Road Race, Drag Racing and many other applications.
Typed all that just off the top of yer head then Grog? :confused1: :clapping: Good man!! :onya:
Col, copy n paste a good tool. Does explain i hope.Basically for super fussy set ups. A bit advanced for me.
The explanation seems a bit chinesium to me.
Basically these valves allow more fine tuning of fork Rebound, compression and damping
Thanks for helping Eric, i just pasted what site said. Yours easier.
I will describe my opinions after few set ups when my friend will put them on. I also note what oil with will be in forks :onya:
Sorry to resurrect an old thread.... but im pulling my hair out.
Quick recap before my current issue.
Changed fork seals,
10w oil 108mm Air Gap
New pads
Cleaned calipers
Battleaxe tyres fitted
Bike handles fine, can let go of the bars and the bike tracks straight with no wobbles or issues. Brakes feel good & no pulsing through the lever, floating discs checked with DTI and only 0.002" run out.
PROBLEM......
When braking for junction, traffic lights etc at around 10mph it feels like the front end bobs up & down. Not like a pogo stick, but feels more like up & down with each revolution of the front wheel.
I got the local garage to fit new tyres yesterday & check wheels bearings and they said everything was OK.
Anybody any ideas?
Could it be the 10w oil ?
I doubt it's the 10w oil, sounds more like a brake issue.
Here's something inexpensive to try, raise the front of the bike up so the front wheel can turn freely (Jack or stand under the frame or whatever). Then put a cable tie on the front brake lever with only enough tension to just slightly grab on the disc, then turn the wheel by hand & see if you can notice resistance at 1 spot in particular. If no, increase the zip tie 1 click & check again.
If after doing this, until you can't turn it by hand, you can pretty much rule out brakes & bobbins. If however you do strike a sticking area, check the bobbins in that spot, hell, give 'em all a clean & lube.
Another albeit obscure reason, could be balance weights. New tire on, but is the balance correct? You could probably check this while the front end is up as well.
Just some cheap things to try - let us know how it goes.
Steering head bearings perhaps :whatever:
Fork bushes?
It won't be the oil anyway.
When emma's bike did exactly this.
It was the fork seals that were letting air in on the up stroke but not leaking or letting it out on thr down stroke so basicly pumping to forks solid .
I stripped both folks replaced both seals all the bushes and the fork oil .
They've been fine for the next 10k miles .
:cheers:
I've checked the discs using the cable tie method and all good.
Set the suspension to "standard" setting yesterday and still felt the same. Softened rebound 2 clicks today and was slightly better but could still feel it.
Seth I'm starting to wonder if it could be the same issue and I need to change the seals again. 🤔
I'll have another fettle with suspension settings tmrw.
Driving me mad now 🤯
I think I've came to the end of my abilities.
Adjustments with the compression & rebound make minimal difference to the front end "bounce" under slow braking.
I had the wife on the back on Sat and it was actually a little less noticeable so thinking maybe the back end is causing the front issue. Clutching at straws really.
Might have to PAY an EXPERT 😪