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Showa forks rebound query

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greenman1966 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote greenman1966 Quote  Post ReplyReply Direct Link To This Post Topic: Showa forks rebound query
    Posted: 26 Nov 2019 at 21:13
So, from my testing anything more than 1/2 turn out is causing issues. Is the needle too steep in its taper? 
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Spoonz View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Spoonz Quote  Post ReplyReply Direct Link To This Post Posted: 26 Nov 2019 at 21:27
Depends on the year of the Showa forks, they got better over the years. But sounds more like your forks may have an issue. Have they ever been serviced. 

I have radial Showa on my rsv and they are the nuts. Much preferred over ohlins I’ve had before as a road fork. 
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IanG View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote IanG Quote  Post ReplyReply Direct Link To This Post Posted: 27 Nov 2019 at 17:35
Can only comment on Showa's fitted to the range of twins, no idea about the V4's but rebound is extremely weak whatever,although yes,they are a very abrupt taper.

Only the first turn or so out from fully in actually does anything as after that they are effectivelly wide open

For what it's worth the 2002 Axial Mille and the radial 2008 Tuono both share the same internals as far as I've seen,only the bottom legs are different to mount the later calipers.

Actually that's not completely true,the T has one 0.017" shim less in it's compression stack,probably due to the riding position and less weight over the bars Wink



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blacklines View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote blacklines Quote  Post ReplyReply Direct Link To This Post Posted: 28 Nov 2019 at 11:20
Yeah the needle does most of it's range in the first half turn. Think it's a known issue. Quite sensitive in that range though if you're careful with the screwdriver. 

What issues?
Owen
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greenman1966 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote greenman1966 Quote  Post ReplyReply Direct Link To This Post Posted: 28 Nov 2019 at 20:22
Issues are that anything more than 1/2 turn out on the rebound makes the compression damping harsh. So I'm thinking of a racetech kit to get the compression side of the damping circuit operating correctly because it seems to me that the shim stack is too stiff. I need a local expert here in nz to talk this through properly. 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Spoonz Quote  Post ReplyReply Direct Link To This Post Posted: 28 Nov 2019 at 21:55
That sounds counter intuitive. Adding rebound increases compression to a degree so if your taking out rebound the compression should get softer. 

Having said that you will never get them as good as ktech internals no matter what you do to the stock cartridge. 
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IanG View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote IanG Quote  Post ReplyReply Direct Link To This Post Posted: 29 Nov 2019 at 17:30
Probably just confused,I agree there is an interaction between compression and rebound although I'm not sure if it's linear enough to be noticed by a layman when we're talking a few clicks.

However taking out what little rebound they do supply as stock will probably show up the harshness on compression even more as there's now no damping control per se just resistance.

I agree regarding the Ktek thought,but one can have hours of fun and learn quite a bit by stripping out the Showa cartridge and experimenting with the shim stacks,valve bodies,oil levels etc.

A spare set of fork legs come in handy here as you can make internal adjustments and just swap in the legs,much less mess that way.

If the rider is on the err chunky side Wink like myself then setting sags can be difficult using the standard springs as they're a tad on the soft side I found,stiffer units could help with the harshness as the damping will now be doing less of the springs job.

Seems counter intuitive I know but backed up by comments from Maxton among others,unfortunately most so called suspension guru's will keep all their info to themselves and charge you for a best guess fix that someone else never complained about.

I can also highly recommend some swapping of shims between the comp and rebound stacksWink .

If it doesn't do what you hope then just change it back,you'll learn loads about cause and effect.

As I recall the shim stacks dictate the damping curve and bleed screws move the curves around so not a great deal can be done with the standard bleeds. 

I know Ohlin's bleeds swapped out in favour of KTek's worked wonders on the  Ohlins equiped Duc 1098s,not sure if they do any for the Showa units though.



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