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  #31  
Old 06-08-2018
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...Jeff would have 20kgs on me...
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Originally Posted by JJW View Post
...I'm about 112kg plus gear now. Good food in Canberra!
Edit: Jeff would have 35kg on me... I was being nice for once Jeff.

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Originally Posted by tonyg View Post
You've always liked em firm Pete
.
Safety Tony. A firm fork might be tiring but it won't collapse if you hit a big flat-lander. Hangover from having a kid who could bottom a Kenworth, I guess.
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  #32  
Old 06-08-2018
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Safety Tony. A firm fork might be tiring but it won't collapse if you hit a big flat-lander. Hangover from having a kid who could bottom a Kenworth, I guess.
Still one of my favourite vids of Robbie
Phenomenal and smoooothe

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  #33  
Old 06-08-2018
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Still one of my favourite vids of Robbie

Phenomenal and smoooothe





Yesss!

Robbie must have been running CC forks with .52s!!! Hes a machine.
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  #34  
Old 10-08-2018
bowser bowser is offline
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tonyg, clear your inbox. I'm unable to reply cause it's full
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  #35  
Old 10-08-2018
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tonyg, clear your inbox. I'm unable to reply cause it's full
Sorry Wayne, all clear now
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  #36  
Old 11-08-2018
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I got out again today, repeat of same loop as last Sunday....93kms of 2nd and 3rd gear ST, some flowy bits but 75% rocky rooty logs at awkward angles etc. It was a little bit drier today, so would expect it to feel a but harsher.

After bleeding the air out of the fork and straightening the front end since last ride, the forks were back to their best.

10kms into the loop, I felt some harshness creeping back in..... I had prepared for this by jamming a philips head under my bar pad. I popped the air screws with the front end unloaded and sure enough, air (and some oil) was pissing out. Fork went back to being awesome at absorbing trail trash, but no diving etc. Spot on.

I am a bit surprised to see that the forks are building pressure that can be felt so quickly. Previously, I would bleed my OC forks a few times per year. My Explore forks tended to like being bled every ride, but feeling a difference after 10kms seems crazy.

Also, when I pop the screws on this fork immediately after pulling up, I get a mess from oil also coming out. I seem to recall reading about someone modifying the caps to allow the air a less tortuous path to exit, I might have to revisit that. I have bleeders on order...actually some turned up Friday but had the wrong thread pitch!

So I kept experimenting over the 93kms, I must have bled the fork 10 times throughout the day. It was a worthwhile exercise each time. On the one hand I am glad, as I was a bit irritated by the end of the long ride last week that the performance improvement seemed to drop off, but on the other hand, it appears I have a solution. I stopped and bled before some known long and rocky sections.......I blasted through better than ever before in the last 5 years I have been riding said tracks. Previously I was getting the "hurry along" through these sections, today I cleared a gap and my hands weren't bleeding.

Which reminds me, I have been one to get beat up towards the end of these rides. Last week and today I finished far fresher than usual. I am still happy with the forks, but like any suspension, requires some fine tuning to get the best out of it.

I may have bottomed the fork today. It didn't blow through and was not harsh. I didn't stop to examine the legs and don't have an o-ring/zip tie on to confirm how deep I got. I wasn't surprised, it was a 4th gear downhill launch. More importantly, the bike took off straight, didn't pitch, and on landing was controlled without a wild bounce.

So my final verdict on the fork....needs bleeders, maybe look at raising the oil level slightly to help in the really fast stuff, but overall it is a keeper.

The rear end is going to get some attention next.
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  #37  
Old 12-08-2018
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Originally Posted by JJW View Post
I got out again today, repeat of same loop as last Sunday....93kms of 2nd and 3rd gear ST, some flowy bits but 75% rocky rooty logs at awkward angles etc. It was a little bit drier today, so would expect it to feel a but harsher.



After bleeding the air out of the fork and straightening the front end since last ride, the forks were back to their best.



10kms into the loop, I felt some harshness creeping back in..... I had prepared for this by jamming a philips head under my bar pad. I popped the air screws with the front end unloaded and sure enough, air (and some oil) was pissing out. Fork went back to being awesome at absorbing trail trash, but no diving etc. Spot on.



I am a bit surprised to see that the forks are building pressure that can be felt so quickly. Previously, I would bleed my OC forks a few times per year. My Explore forks tended to like being bled every ride, but feeling a difference after 10kms seems crazy.



Also, when I pop the screws on this fork immediately after pulling up, I get a mess from oil also coming out. I seem to recall reading about someone modifying the caps to allow the air a less tortuous path to exit, I might have to revisit that. I have bleeders on order...actually some turned up Friday but had the wrong thread pitch!



So I kept experimenting over the 93kms, I must have bled the fork 10 times throughout the day. It was a worthwhile exercise each time. On the one hand I am glad, as I was a bit irritated by the end of the long ride last week that the performance improvement seemed to drop off, but on the other hand, it appears I have a solution. I stopped and bled before some known long and rocky sections.......I blasted through better than ever before in the last 5 years I have been riding said tracks. Previously I was getting the "hurry along" through these sections, today I cleared a gap and my hands weren't bleeding.



Which reminds me, I have been one to get beat up towards the end of these rides. Last week and today I finished far fresher than usual. I am still happy with the forks, but like any suspension, requires some fine tuning to get the best out of it.



I may have bottomed the fork today. It didn't blow through and was not harsh. I didn't stop to examine the legs and don't have an o-ring/zip tie on to confirm how deep I got. I wasn't surprised, it was a 4th gear downhill launch. More importantly, the bike took off straight, didn't pitch, and on landing was controlled without a wild bounce.



So my final verdict on the fork....needs bleeders, maybe look at raising the oil level slightly to help in the really fast stuff, but overall it is a keeper.



The rear end is going to get some attention next.


I purchased these for my Ohlins forks as I was having similar issues with air. Not a problem anymore

https://www.airprofork.com/moto/
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  #38  
Old 12-08-2018
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...my final verdict on the fork....needs bleeders, maybe look at raising the oil level slightly to help in the really fast stuff...
You're having issues with high air pressure in the outer fork but you're considering lowering the chamber volume? Fro, this is the most tunable fork WP ever made but you're thinking of using a tuning technique from 1973?

The CC fork has many options for controlling bottoming without overloading the outer oil volume. Huck valves for instance. The side-oil load in CCs is there to mainly lube the slide-metals and seals. I always run 330ml in mine and tune the rest of the fork to suit. With Simons seal grease on the main seals, even after 4 hours of S/T they build SFA pressure.

Loading up the side oil will help more with blowing fork seals than anything else.
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  #39  
Old 12-08-2018
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Quote:
Originally Posted by JJW View Post
...
After bleeding the air out of the fork and straightening the front end since last ride, the forks were back to their best.

10kms into the loop, I felt some harshness creeping back in..... I had prepared for this by jamming a philips head under my bar pad. I popped the air screws with the front end unloaded and sure enough, air (and some oil) was pissing out. Fork went back to being awesome at absorbing trail trash, but no diving etc. Spot on.

I am a bit surprised to see that the forks are building pressure that can be felt so quickly. Previously, I would bleed my OC forks a few times per year. My Explore forks tended to like being bled every ride, but feeling a difference after 10kms seems crazy.
...
Yeah, my CC forks built more pressure in them from day 1 (in stock form, before I did the coatings) and even then I was quite surprised at how much of a difference releasing the built up pressure made. I guess with the lack of stiction/friction with the coatings it makes the forks even more sensitive to the pressures, coz like you I find that I can actually feel when the pressure needs to be released. I am trying to get into the habit of releasing pressure just before pulling away again after a stop, but am finding the forming of the new habit difficult.

I got some Motion Pro fork bleeders with a little button on top of them to press and release pressure - you can hear the air hiss out. But i have also noticed the bleeders are getting a little oily and messy, so presume the the oil sloshes around quite a bit. Either that, or I have not tightened them enough so that oil can leak by the O-ring... I dunno

Quote:
Originally Posted by JJW View Post
...
I may have bottomed the fork today. It didn't blow through and was not harsh. I didn't stop to examine the legs and don't have an o-ring/zip tie on to confirm how deep I got. I wasn't surprised, it was a 4th gear downhill launch. More importantly, the bike took off straight, didn't pitch, and on landing was controlled without a wild bounce.
...
I put the O-rings on my forks and have noticed that I am using far more of the stroke now, but have yet to bottom the forks out yet.

Quote:
Originally Posted by JJW View Post
...
So my final verdict on the fork....needs bleeders, maybe look at raising the oil level slightly to help in the really fast stuff, but overall it is a keeper.
...
How much oil are you running at the moment? I used to run 320ml, but have found I am preferring 350ml now. As I said, I am yet to bottom my forks, so I reckon around 350ml is a good setting for me and my riding.

Bleeders are a must for sure!

Quote:
Originally Posted by JJW View Post
...
The rear end is going to get some attention next.
Yup - I noticed the rear end needed work on mine too. My shock still had the piston reservoir so I just put a Racetech Bladder on mine a couple of weeks ago. In my opinion it has made the rear better - more compliant - so the theory of the larger surface area of the bladder creating a better hydraulic advantage seems to be true.

I recently serviced my mates shock that has a bladder and the oil came out like a milkshake or frizzing coke, which worried me (after seeing Slavens video on why he dislikes bladders). But upon inspecting his bladder it seems that it split and so the pressurized gas from the bladder would have made the shock into a soda-stream for the shock oil, and that was the problem. He did have over 100 hours on the shock since the last service, so I guess somehting had to give!

I'm gonna hold off on exotic coating the shock shaft for the moment as I am unlikely to keep this shock, and I am not sure how much advantage I would feel from it either. What are you planning on doing to your shock?

Quote:
Originally Posted by Cuffie View Post
I purchased these for my Ohlins forks as I was having similar issues with air. Not a problem anymore

https://www.airprofork.com/moto/
I was very interested in those, but was put off by the price. From what I could tell, basically those bleeders work on a similar principle to your fork fluid damping in that they have a very small hole for air to pass through with those little aluminium inserts each end of the pipe, so when the forks compress some air is forced out until a "hydraulic lock" (because air is a fluid that flows just like your fork fluid does, albeit air is a lot less viscous) prevents any more air being pushed out - orifice damping being velocity squared and all. Then when the fork uncompresses air is sucked back into the fork, but because rebound is relatively slower than compression the bleed holes don't prevent air getting back into the forks. That would mean finding the right size inserts would be critical though, unless there is some special tech in that aluminium housing you mount between the bars.

Have you openned up that aluminium piece as a batter of interest? Is it much more than just some foam to filter the air so that it soaks up any oil ejected in compression, and filters out particles to prevent them being sucked into the forks when the uncompress? Or are there complex channels and things in there too?

I have knocked up a poor-mans version of those bleeders which I am intending to test after my next fork service to see if they work. But if you can shed any more light on how your fancy jobs work it might inform me a little more on what to do to mine.
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  #40  
Old 12-08-2018
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JJW - forgive me if Im stating the obvious, but are you getting your front wheel off the ground when you bleed the forks? I never had oil blow out of mine. I found the fork built pressure after a service for about 15hrs, then very little air, then as it neared time for a service it built air again. The bleeders help so you can pull the bike over on the side stand and get the front up to bleed.
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