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air forks off road

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I would like to hear how people are liking there air forks in off road type enduro and hare scrambles? I have not had a chance to try them yet. Im sure there are some major differences between my mtn bikes air suspension and the new generation mx air forks. But i love them on my mtn bike so i was just wondering how people are liking them far from the mx track and the truck? Thanks

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Also in for some opinions on this. Haven't ridden air forks on a dirt bike but have been running them on MTB for a LONG time.

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well i must say there awesome, but they need a fix with the midvalve and then a little tuning and they gonna be really sweet ,the problem is that they only is on 2 models for 2 years (honda crf 450 kx450)

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From what I rode I think they would suit off road better than mx with the std settings

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I see that for 2015 a few more models will get them. Luckily for me two bikes that are on my list the crf 250 and the rmz 450. I understand they both will have the showa triple air. I am more interested in the honda for an off road conversion. Since honda doesnt seem to care about updating the 250x. But either way it seems the air forks will be the future.

What im not understanding though is on my yz the forks would build up pressure from the heat they generated and would need to be bled. So on these new forks what happens after you set them at 35psi for example and ride for a few hours does the pressure not go up and change the spring rate causing them to get stiffer? Thanks again

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They do go up about one rate I believe

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Same thing happens with spring forks, but nobody talks about it...

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So you just set them a little lower to begin with. Seems easy enough. Is there any info out on the triple air forks yet? Other than just brochure stuff.

Also are there any plans to have a air shock as well in the near future? Seems to me the front and rear could be balanced out much better. Thanks again

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Ktm are said to come with air shock and fork in 16 , the triple chamber air fork is a exact copy of the works bikes forks

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I imagine the triple air forks will be better then the single chamber of air. I would hope the triples could be adjusted for the initial stroke, mid and bottoming resistance by adjusting each chamber. Doesnt seem like you would even need clicker adjustments as well. But i guess you could fine tune even more. The 2015 crf 250 is looking better all the time. Im surprised they didnt release them on the crf 450 also. Maybe next year. Do you know of anywhere on the net they show a schematic or video showing how the internals of this triple works? Seems like if the single air works good off road the triple could be tuned to near perfection off road.

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Hi guys I want to weigh in on this one.  

 

The basic feel of the air fork (PSF or TAC)  can be described as a very progressive one. And that (spring characteristics) can't really be changed. We have been testing the Showa TAC for several weeks and in some ways I think it is merely a more adjustable and reliable version of the Single Air Volume such as the PSF. While its true the chambers can all be tuned at timed a little differently they still have an exponential characteristic. And there is no mechanism by which a rapid pressure rise can be delayed or buffered. (I intend to work on that.)

 

Lets compare and contrast a bit.

PSF:

The single Air volume and mechanical balance spring can give a nice feel at the top of the stroke but its biggest issue is that it falls flat in the middle, as the pressure is not increasing (due to internal volume) fast enough. That gives the fork a soft mid stroke, as pointed out, the midvalve can aid in this feel, but its adding damping, and not spring rate and these are very different things. (Especially for off road that requires soft settings!) So the rider is stuck, either jacking the initial pressure up at the cost of top stroke feel to get more in the middle, or raising the oil volume to make the super exponential rise occur sooner for a very stiff  bottom 1/3.  I'm not saying you can't find a sweet spot, but its not easy, and its very narrow. Of course longer balance springs and all sorts of other things can help to some degree. The other major issue that a small nick on the tube or seal issue causes a catastrophic loss in rideability in a longer offroad event. We built our SFF conversion with the intent of spring performance and feel, but what I discovered was the market wanted ease of use and reliability.  More than 70% of our SFF conversions have been offroad based. 

 

TAC:

I'm still very much learning about the TAC. But to date.. It still has a distinct air-fork feel but it is exponentially better in terms of adjustability. The rider can no tune the balance spring and the duration of the balance spring can be much longer, without all the mechanical issues that can come with super long balance springs. It also is also then be default much better in the middle. No effective decrease in rate that the PSF suffers from. So while it does not fall in the middle it does however act very progressively.  And the big point for off road riders, it is 100% more reliable. A small seal failure will leave you with a fork that is only slightly compromised. 

 

Here is a link to a video I shot that outlines our work to date.

 

 

Here is a first plot of the load and rate.

 

 

 

 

 

 

 

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great post...it would seem they have a few issues to work out before air forks are really the standard..

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