BMW S1000RR shock conversion question

[unfazed]

zero miles, £40 including postage. i couldn't resist:


going to fit this in conjunction with a forks strip and overhaul. i'll post the results once done. i do my own mehcanical work but know very little about suspension so will be subjective. current shock is the standard fzs unit that i had re-built around 5k miles ago.

Set it as standard first all the damping settings at 4, but wind the preload up full. 

[bludclot]

fitted this and rode the bike yesterday. ride is definitely improved.


unfazed is absolutely correct - the bottom bolt needs to be 41.5mm shouldered, i have the standard bolt in there but this means that the nut end of the shoulder is only within the shock fork by 2mm (or so) of the 6mm available. an option i did consider was taking 1mm off each of the shock fork legs - seeing as the original shock fork legs are 5mm it should be ok - but i would rather fit a longer shouldered bolt. so, can anyone supply me or point me towards such a bolt please?


i did not find it necessary to glue washers to the top of the shock for fitting. it was straight forward to slide the mounting bolt through the frame then through the first washer then through the shock then slide the second washer into the gap then tap the bolt home, easy.


my other issue is at the top of the shock however. the original shock when bolted in just at the top had no real lateral movement. the bmw shock moved all over the place however, not encouraging at all. the shoulder of the bolt was a snug fit into the drilled bushes so i figure the issue is elsewhere, most likely with the washers.


so to conclude, good upgrade but not a straight forward bolt in job as has been suggested in the past.

[NorthWestern]

Odd, mine went straight in.  The only thing I did was make some new bushes for the top, I didn't fancy washers so removed the original bushes and made new ones.  (and put a stronger spring on). The bottom bolt went through fine, like standard.

[unfazed]

Odd, mine went straight in.  The only thing I did was make some new bushes for the top, I didn't fancy washers so removed the original bushes and made new ones.  (and put a stronger spring on). The bottom bolt went through fine, like standard.

Was yours the 2010/2011?

The spring on the 2012/2013 is a heaver rated spring and should suit anybody up to about 150kg.

Combined weight of my wife and I is 140Kg and it handles great with the two of us on it.

The top of mine was sloppy loose until I torqued up the bolt/nut properly.

I would not advise touching the fork, but get a top shock bolt from a breaker and cut it down to fit. The ones from the 600 and 1000 are the same so plenty of them out there.

Collected the 10mm spacer for the spring today and will fit it over the weekend to allow me play with the static sag.

[NorthWestern]

2013. The spring was stiffer than the std fazer one but not by much.  I do a lot of two up riding so put a stronger one on

[unfazed]

2013. The spring was stiffer than the std fazer one but not by much.  I do a lot of two up riding so put a stronger one on

Any idea what the spring rate of the spring you put in is? I have an old Fireblade shock in the garage and the spring is the same size but I must check the spring rate of it as I cannot remember which year Fireblade it was taken from.
Out of curiosity any idea of the combined weight of both of you, I was out with my eldest son on the back and our combined weight was about 170Kg and the spring felt a bit soft only on really bumpy roads. If I go touring on it this year I might need to upgrade the spring if increasing the static sag does not help.

I should be able to adjust the static sag more when I fit the 10mm spacer to the bottom spring seat..

[NorthWestern]

I don't unfortunately, we had a few springs and this one was the same thickness as the BMW spring but had less coils hence stiffer (and felt stiffer when fitted).  I think its off a ZX10R.  Combined weight probably around 170/180 + top box and contents)

[JoeRock]

[quote author=NorthWestern link=topic=4976.msg147217#msg147217 date=1399572571]
2013. The spring was stiffer than the std fazer one but not by much.  I do a lot of two up riding so put a stronger one on

Any idea what the spring rate of the spring you put in is? I have an old Fireblade shock in the garage and the spring is the same size but I must check the spring rate of it as I cannot remember which year Fireblade it was taken from.
Out of curiosity any idea of the combined weight of both of you, I was out with my eldest son on the back and our combined weight was about 170Kg and the spring felt a bit soft only on really bumpy roads. If I go touring on it this year I might need to upgrade the spring if increasing the static sag does not help.

I should be able to adjust the static sag more when I fit the 10mm spacer to the bottom spring seat..
[/quote]


That's really not the way to do it mate - for linear springs increasing the static sag isn't going to make a blind bit of difference (it'll just make the ride height about right), it's just where the suspension sits in its stroke. Practically all it means is you'll have a lot less suspension travel to cope with any big bumps you hit, and if the spring is that soft it'll bottom out!

[unfazed]

Joe

Appreciate the comment, but I am aware that changing the static sag cannot change the spring rate, but if you read what I said "If increasing the static sag does not help."  and since it never bottomed out with the combined weight of 170Kg, I was more concerned about the drop in ride height.. It felt softer than I liked which is why I will consider changing the spring. The spacer I had made was to allow me play around with the ride height since the standard shock set up will not allow me go lower than 20mm static sag and I would like to try it at 10mm.

The reason I asked the question about the Spring rate of the spring North Westerner used is that I have 2 springs which are the same dimensions as the S1000rr one, 14.7Kg 600 fazer and a 12Kg RR Fireblade. Just checked the Ktech site and they list all RR Fireblades from 2004 to 2013 at 12Kg and since it came off a RR Fireblade solves the problem not being able to  remember which year it was.
The 2012/2013 S1000rr is as far as I can make out is about 9Kg and 12Kg is to big a step since it is pretty good as it is.

Unfortunately K Tech do not cover the later S1000rr or ZX10 on their site.


When I fitted the Hagon Shock to the 600 it was 14.6Kg and it felt a bit on the soft side 2 up and I changed it to a 16KG one which was perfect. Based on this, ideally I would like to try a 10.5 Kg spring first before going higher.

[nsr500v4]

Look what the postie brought me today 


[smg id=1932 type=preview align=center caption="Shock"]


All we need is some posts on how everyone sets their shock up with rider weights, spring preload etc etc to give everyone the benefit of the knowledge built over over the months of set ups

[pitternator]

I chuckle a bit when folk call the OE shock rubbish. It isn't , its just got way too weak a spring . Ktech  and others did a rebuild which actually worked quite  well 10 yrs back. The full monty K tech is as good as anything out there.... they claim up to ohlins standard..... The OE shock in the picture is maybe 10 to 12 yrs old, never cleaned, never looked after .  Hope you look after the RR one.
Incidentally , just why are so many RR shock about ?...is it leftovers from racers  fitting decent stuff like K tech shocks !  :lol

But if its cheap and you like it , go ahead. Personally the weakness in all this fitting of shocks from other bikes is setting yer bikes up, and hoping you have the right spring to get the sag right. You have to get the sag right before you even consider damping adjustments. I do applaud ingenuity and perseverance. But do remember if you have  a knackered shock on yer bike..ANYTHING will feel marvellous. But it could still be far from ideal. Ask me how I know !

[unfazed]

I never considered the OEM shock rubbish, I thought it was a pretty good shock, but as you say the spring was way to soft. However when I saw a  zero miles 2012 S1000rr for sale in the USA for $120 including postage, I bought it. A new spring was £105 including postage in the UK. I decided to try the S1000rr option.
The advantage of that shock is that is raises the rear 10mm without any modification to the dog bones and improves the turn in on the fazer.
Since it is made by Sachs is is also a good quality item and was much more cost effective than buying a new spring or shock.

[NorthWestern]

Is that the ktech rebuild which replaced the adjusters, shim stack, shock body etc?  I doubt they can offer anything in the same price bracket really.


Racers don't replace their shocks with a £300 "Sport" shocks they get the big ones ~£1000 which isn't really a good comparison.  For less that £100 you can have a modern design shock with hardly any miles on it and a spring suited to your weight. then you can play with the settings which some folk enjoy doing.

[JoeRock]

Would someone with one of these be kind enough to let me know a few measurements?


I need the length of the shock, as close as possible, from centre to centre mounting holes
Also the weight of the spring on there as stock
and the measurements accross the mount at the top, and inside the bottom?

Basically, I'm considering fitting one to my zx9r if it'll fit and its about right!

[unfazed]

http://foc-u.co.uk/index.php/topic,4976....#msg132497

I can check the rest tonight as I have one in the garage

[unfazed]

Finally got around to fitting the spacer to the S1000RR shock to enable me to set the static sag to my liking.
See picture it fits nicely

Joe Rock I have 2 shocks and both are slightly different top and bottom one is .15 more and the other is .15 less then the 29.5mm as the average of both measurements

[JoeRock]

Cheers for that Unfazed!


Hadn't realised the info was on there already!  :o


Unfortunately it's way to short for mine, Zx9 is about 337mm so something with a 20mm drop would have to be modded, which would probably make it as expensive again!

[bludclot]

i had these made up from stainless steel at my local machine shop:





here's the longer shoulder of the bottom bolt and the standard bolt against the bmw shock:





many thanks to unfazed for his measurements, spot on.


i had two sets made so one is spare. it owes me 15 so if anyone wants it..... my machine shop man said that he can make more sets if required.

[Paolo_69]

Hello there from Italy  8)
after reading about this mod, I have replaced my original shock with a S1000RR '12 with 4000 km.
The shock works very good (everything works better than the original), the only proble is that with the shock fully preloaded I have a statit sag of 27 mm (against a reccomended 10-15) and a rider sag of 55 (against a reccomended 30-40). My weight is 90 kg
This make me thinking that the spring rigidity is correct, but the spring is too short, it'd be 10-15 mm longer.
What you think? Could I resolv with a 10-15 mm spacer under the spring?


ps sorry for my bad english...

[JoeRock]

Hello there from Italy  8)
after reading about this mod, I have replaced my original shock with a S1000RR '12 with 4000 km.
The shock works very good (everything works better than the original), the only proble is that with the shock fully preloaded I have a statit sag of 27 mm (against a reccomended 10-15) and a rider sag of 55 (against a reccomended 30-40). My weight is 90 kg
This make me thinking that the spring rigidity is correct, but the spring is too short, it'd be 10-15 mm longer.
What you think? Could I resolv with a 10-15 mm spacer under the spring?


ps sorry for my bad english...

You need a stiffer spring mate, by quite some way too!