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Shorter shock 200x5...
 

[Closed] Shorter shock 200x57 to 190x50

 hora
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[#4026559]

Right or wrong? Less psi gives you a shorter eye to eye but sadly will bottom out.

So a shorter coil shock will avoid the neg above?

Just 10mm difference 'should' be ok considering what less psi in an air shock would do?

I want a stiffer shock and a slightly lower BB. Running low psi in my existing air shock makss the bike feel alo better...but the shock hits on its internal stop/bottomed out alot.. The frame is a 09 spesh Enduro which feels quite tall normallu


 
Posted : 31/05/2012 7:10 pm
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3mm shorter under full compression - as long as it doesn't foul, it should work.


 
Posted : 31/05/2012 7:14 pm
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That will give you a slacker head angle/lower bb but also reduce travel. Have a google for a suspension design program called linkage, it will let you see what difference this would really make. I'd say to get what you are after you need a shorter eye-eye but with the same stroke

HTH
Matt


 
Posted : 31/05/2012 7:14 pm
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edit: d'oh I'm a fool.


 
Posted : 31/05/2012 7:16 pm
 hora
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Reduced travel not a biggy compared to the lower/slacker benefit.

Ive heard that before, I wonder if the figures would be in my 'favour'


 
Posted : 31/05/2012 7:16 pm
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Off-set bushings? Would do the same without changing the shock, might not be as much as 10mm though. Also is the shock currently in the low position?


 
Posted : 31/05/2012 7:19 pm
 hora
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Agree but I need a stiffer shock anyway as the AFR shock just isnt great


 
Posted : 31/05/2012 7:21 pm
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3mm? Surely it would be significantly more?

Not only is the i2i shorter, so it the stroke.


 
Posted : 31/05/2012 7:22 pm
 hora
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What does stroke mean?

Is it a %?


 
Posted : 31/05/2012 7:24 pm
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Surely being 10mm shorter and ~2.5:1 suspension ratio that's going to drop your BB by an inch! And the enduro is already pretty low in the low/slack setting!

Offset bushing would drop it 10mm or so which would be more usefull probably.

Maybe try running more rebound damping so that the shock stays further into it's travel while decending over rough stuff without lowering the BB to unusable levels on the climbs and smoother pedaly sections?


 
Posted : 31/05/2012 7:25 pm
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Length of travel of the shock - 50mm in this case.


 
Posted : 31/05/2012 7:26 pm
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Stroke is the 'travel' of the shock, so a 200x57 shock is 200mm from the centre of the 2 eyelets, and 57mm travel, 190x50 has 7mm less.


 
Posted : 31/05/2012 7:29 pm
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(distance between centre of shock mount eyelets) eye-to-eye / i2i = 200mm or 190mm

(distance shock shaft travels until maximum compression)
stroke = 57mm or 50mm


 
Posted : 31/05/2012 7:29 pm
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what bars, stem and fork are you running?


 
Posted : 31/05/2012 7:29 pm
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TINAS beat me to it


 
Posted : 31/05/2012 7:30 pm
 hora
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Enduro is 14 in low BB setting. With my Mazz forks I bet its higher!


 
Posted : 31/05/2012 7:34 pm
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Hora, you're obsessed with slackness.


 
Posted : 31/05/2012 7:48 pm
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Bear in mind that's 14" un sagged, so 1/3 sag makes it 12". Dropping that another inch would make it 11", cranks are 7" so that leaves 4" clearance for pedalling even before it bobs, mash the pedals and it'd probably catch the pedals on a fire road if it's anything lumpier than gravel!


 
Posted : 31/05/2012 7:54 pm
 hora
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I looked at th Blur4x stats...thats 12.6!

Im obsessed with tinkering 8)


 
Posted : 31/05/2012 7:57 pm
 GW
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With the 190 x 50 you'll lower the BB and slacken it out when static but when bottomed out it'll actually be higher and steeper than before.
Sagged the same percentage it will be lowet and slacker.


 
Posted : 31/05/2012 8:00 pm
 GW
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TINAS is talking pish BTW


 
Posted : 31/05/2012 8:02 pm
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GW - Member

With the 190 x 50 you'll lower the BB and slacken it out when static but when bottomed out it'll actually be higher and steeper than before.
Sagged the same percentage it will be lowet and slacker.
Posted 4 minutes ago # Report-Post

GW - Member

TINAS is talking pish BTW
Posted 2 minutes ago # Report-Post

Which bit, his BB will be an inch lower, on a bike that already has quite a low BB.

Or the bit about it being lower when bottomed out

190-50 = 140mm

200 - 57 = 143mm

Longer shock makes it higher and steeper, thus when bottomed out it's slacker too.

You have 11 minutes left for a stealthy edit ๐Ÿ˜›


 
Posted : 31/05/2012 8:08 pm
 hora
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So should I take the experiment 65 quid further???


 
Posted : 31/05/2012 8:11 pm
 GW
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All of what you said is wrong.. tick tock...


 
Posted : 31/05/2012 8:14 pm
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*checks calculator*

yep, 143mm is still bigger than 140mm, and longer lengths still make it taller and steeper.............

As for Hora, if it fits and you reckon it'll be an improvement then go for it, if it works we'll all copy you, if it doesn't we'll laugh at your hideously miss shapen pedals after you've mashed them into oblivion ๐Ÿ˜›


 
Posted : 31/05/2012 8:19 pm
 GW
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Assuming a 2.51 ratio
10mm shorter stroke reduces rear travel by about an inch not the BB height (it'll lower a fair bit less)

The eye to eye will be 3mm longer at full travel with the 200mm shock, you do the maths

The clipping pedals on fireroads remark was my personal favourite tho ๐Ÿ˜‰


 
Posted : 31/05/2012 8:27 pm
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190-50 = 140mm - tick

200-57 = 143mm - tick

Starting from a 14" BB and assuming a constant 2.63 (not 2.51)

Original shock bottoms out at 8" BB height (lets assume he's bottoming out fork and shock together and the changes aren't significant enough to make a difference between BB height changes and suspension travel).

200-140 = 60mm, 60*2.63 = 158mm = 6.2", thus his BB is now at 14-6.2 = 7.8", which is lower than 8".

I've got no TV and it's raining so I've got all night (and a pitch in the shed with the shock in bits and a tape measure if it comes to it).


 
Posted : 31/05/2012 8:35 pm
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With the 190 x 50 you'll lower the BB and slacken it out when static but when bottomed out it'll actually be higher and steeper than before.

The eye to eye will be 3mm longer at full travel with the 200mm shock, you do the maths

I just did, hang on a minute, you've changed your mind!


 
Posted : 31/05/2012 8:37 pm
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Mark. Get another Blur 4X. You know you want to...

[img] [/img]


 
Posted : 31/05/2012 8:49 pm
 GW
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Lol

Firstly, a longer eye to eye raises the BB and steepens the HA

With both shocks fully bottomed the eye to eye of the 200mm shock is 3mm longer.(so steeper and higher)

Reducing travel by an inch will only reduce BB height by around 10mm (varies from bike to bike depending on wheelbase/chainstay lengths)


 
Posted : 31/05/2012 8:51 pm
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With both shocks fully bottomed the eye to eye of the 200mm shock is 3mm longer.(so steeper and higher)
Hey, that's my line!

This is your line!

GW - Member

With the 190 x 50 you'll lower the BB and slacken it out when static but when bottomed out it'll actually be higher and steeper than before.


Reducing travel by an inch will only reduce BB height by around 10mm (varirs from bike to bike depending on wheelbase/chainstay lengths)

Assuming the chainstay is around 40mm, and the wheelbase is 1150mm, then dropping the rear wheel an inch will drop the BB by 25*(1150-420)/1150 = 16mm, drop the front fork into it's sag as well and you get the other 10mm.


 
Posted : 31/05/2012 8:54 pm
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I make it:

190-15 = 175 at 30% sag (lower/slacker)
200-17.1 = 183 at 13% sag (higher/steeper)
(difference about 20mm at rear axle, so maybe 12 at BB ? maybe half to one degree slacker HA when JRA)

190-50 = 140 fully compressed (lower/slacker)
200-57 = 143 fully compressed (higher/steeper)
(diff about 7-10mm at the rear axle, maybe 4-7 at the BB ? - I'm guessing that's waaay under half a degree HA)


 
Posted : 31/05/2012 8:57 pm
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Don't bloody encourage him.

He had the lowest bars of all three of us last night yet apparently his still feels high and as for him needing a stiffer shock, last week we all told him to let some air out.

I'm starting to side with binners on all this.


 
Posted : 31/05/2012 9:08 pm
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Blur 4X Hora. Low rise Renthals, 150mm Revelations. Slack, low and mega fast!


 
Posted : 31/05/2012 9:14 pm
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GW has the wrong end of the stick - he's downsizing from 200 -> 190, so the reduced i2i slackens it out... not 190 -> 200.


 
Posted : 01/06/2012 10:24 am
 hora
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Ali did you receive my reply on your shock?


 
Posted : 01/06/2012 10:46 am
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Ah it was you! The Float is new for me, so I'll give it a few weeks of riding, before I decided whether to return to coil.

Until then, I'd rather keep both.


 
Posted : 01/06/2012 11:01 am