How to: fit a BMW s1000rr rear shock to a VFR 400 nc30

[krisztian_andre]

Why is it a shit shocker? HRC linkages are 275 GBP.

[999Gomerz]

Why is it a shit shocker? HRC linkages are 275 GBP.

The BMW is not a shit shock, it is a great shock.

I was referring to the Nitron as the shit shock,

And that it would be much better to get a bmw or gsxr shock and and HRC link tha spend a boat load on a Nitron.

275 gbp plus say 115 for a bmw or gsxr is less than a nitron and you would have a much better set up

[alexwitham]

Nitron. A shit shock.

[999Gomerz]

Yep, its a shit shock.

Tell me who else in top competition is using a remote resivoir that is tethered by essentially a brake hose. No one, because it is old, superseaded technology. They also dont put dual lockrings on their shocks, meaning the preload will change as the single locknut works its way a little loose.

Also, how many world or national championships have they one a proper bike racing championship.

If you want a fancy shock, go for either Ohlins, Showa, hell even K-Tech or Mupo.

[porndoguk]

Judging by StrayAlien's recent post they dont inspire me with much confidence

viewtopic.php?f=22&t=39722

[alexwitham]

Mine feels amazing.

However, I have never ridden with any of the aforementioned.

[krisztian_andre]

Why is it a shit shocker? HRC linkages are 275 GBP.

The BMW is not a shit shock, it is a great shock.

I was referring to the Nitron as the shit shock,

And that it would be much better to get a bmw or gsxr shock and and HRC link tha spend a boat load on a Nitron.

275 gbp plus say 115 for a bmw or gsxr is less than a nitron and you would have a much better set up

I see. So you can use the HRC linkage with the BMW shock on an NC30 unlike the NC35 linkage?

[999Gomerz]

Why is it a shit shocker? HRC linkages are 275 GBP.

The BMW is not a shit shock, it is a great shock.

I was referring to the Nitron as the shit shock,

And that it would be much better to get a bmw or gsxr shock and and HRC link tha spend a boat load on a Nitron.

275 gbp plus say 115 for a bmw or gsxr is less than a nitron and you would have a much better set up

I see. So you can use the HRC linkage with the BMW shock on an NC30 unlike the NC35 linkage?

You can pretty much use any shock with any link, but how well it works is the thing that decides if you would.

The VFR400 and the RVF400 have a major problem in the rear suspension, actually they have two problems;

Lets start by clearing up one thing - THe VFR400 and RVF400 have identiacal links in terms of ratio, one may have a stupid metal rubber bush but they are idential in ratio. THe RVF has a shorter pullarm which does raise th back, but it also makes the ratio more progressive, which is a bad thing........

1- The link ration is very progressive, meaning that it increases rapidly as the rear wheel compresses, great if you are riding two up or weigh over 150kg, but not at all good for edge grip because when the bike is leant over during a turn the loads are their greatest and then when you want to drive out of the corner you are shifting the weight bias to the rear and thus puttting more load on the back end, (this is conuntered by chain pull but this has a minor effect as there is very little HP on a 400). As the rear loads up more, if the link ratio causes the back to be too stiff you will most probably loose grip and spin the back, not the ideal situation when you are trying to drive out of a corner. ie bad situation

2- The ratio again - somewhat. Most modern bikes use a spring that is 100-120 Nmm, where as if you have the standard VFR400 or RFV400 link then you need about a 160-180Nmm spring. This means that the valving must be very different to anything that is being used and developed today, pistion and port sizing as well as shape and shim stack improvements are all targeted around 10-12kg springs. The heavier spring will make a large difference especially on the rebound circuit, as when a spring is compressed it stores energy, The rebound serves to control the release of this energy.

I have been told that some people are putting digressive shim settings in their shocks, but this is not going to fix the problem of the wrong link to start with. The link is position dependant, the shock and thus shim is speed dependant.

bottom line, if you want the best handling rear, use the hrc link and a GSXR or BMW shock. Get an adjustable pull arm and you can adjust ride height his way, they are not hard to make or source if you look on ebay an do a bit of modification. If you are a light fella you may not even have to get the shock revalved or change the spring.

[Drunkn Munky]

Wont you need a shorter shock to use the HRC linkage though? the HRC specific shock Rick O sells is both shorter and as you say fitted with a more common softer rate spring.

[999Gomerz]

Wont you need a shorter shock to use the HRC linkage though? the HRC specific shock Rick O sells is both shorter and as you say fitted with a more common softer rate spring.

Nope,

To give you some idea, if you are using a 310 shock length then you would want a pull arm of 127-134mm depending on gearing, if the shock is 314 then you would use a pull arm 131-139mm.

I would not use a shorter shock than 310 with the hrc link. We are using a spring that is about "rider weight / 8.5-9"

We are not using anymore that 35mm of shock travel.