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CraigG

VFR1200 shock installation

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So figured i  would post up a thread about what i got up to at the weekend. that is, unexpectedly fitting a VFR1200 shock to my 5th gen.

 

I had been looking for a budget upgrade to the 55k mile rear shock on my VFR, and looking at the numbers i figured that a VFR1200 shock would be a pretty good match. I managed to snag a VFR1200 shock off ebay a couple of months back for 70£ (mint condition too, bargain!) and i was planning to do a complete overhaul of the bikes suspension, with VFR1200 front end, and the rear shock to match, i have been gathering parts and planning the work to commence towards the end of April

 

Then on Saturday, while recommissioning my SV650 from its winter hibernation, my VFR decided it was jealous, and decided to spill its rear shock guts all over the floor when i pulled it out of the shed, so after giving the SV its once over. I spent the rest of the day removing the rear shock, and mocking up the VFR1200 shock. 

 

side by side, the shock is about 4mm shorter:

dMChNgj.jpg

 

Apologies now for the lack of pictures from here, but i was intent on getting it fitted before it went full dark! 

 

installing it "out of the box" as it were,  the pre-load adjustment platform banjo makes contact with the exhaust header, so that wasn't going to work. rotating the shock through 180deg fixed that issue, but brought about 2 more. 

1. the rebound adjustment at the bottom of the shock now faced inwards, towards the rear brake pedal and above the exhaust collector, this makes it not easily accessible for making adjustments. 

2. the hose coming out of the preload adjuster now pointed forwards, which meant there was nowhere to mount the adjustment body. 

 

so, with the top mount clamped up in a vice i rotated the damper portion of the shock 180deg(it will spin freely, but obviously has a large spring pressing against it, a large adjustable spanner assisted), so that the rebound adjuster now faced the same way as the outlet of the pre-load platform. 

 

then, i cracked off the banjo bolt going into the preload adjustment platform (just enough to allow me to forcably rotate the union, but not enough that anything leaked) and rotated that pipe 180deg, so when fitted it now exits towards the back of the bike, i also did the same to the banjo going into the adjustment knob, so that the mounting tab sat pointing upwards this will let me get a simple bracket to bolt the adjuster knob to the bottom of the subframe. 

 

 

 

I still have to fabricate the bracket to hold the adjustment knob, for now its just cable tied to the subframe. and i have ordered a spacer to fit between the clevis and frame to make up for the 4mm difference in length.

 

it was dark when i finished, but i will get some pictures today when I'm home

 

i have not been out for a ride on it yet, but sitting on it (jumping up an down on it too), it feels a billion times better, it will be amusing to see how the ancient front end compares to the new rear out on the road, needless to say i cannot wait to get the front end sorted as well.  

 

 

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Hi, This is interesting I was looking at the 1200 shock to replace my 6th gen 50k rear. But didnt find much info to help me decide so plumped for a new Ohlins STX which was going cheap at £300, just waiting for it to arrive from Italy.

But my son has a 5th gen with nearly 60k so waiting to see how yours feels on the road?

By the way whereaboots in Scotland are ye frae? I am from Paisley moved 15yrs ago.

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sorry chaps! 

 

ok so holy cow its WAY WAY better, really showing up the front end now (in progress!)

 

it has lowered the rear end as expected (roughly 780mm seat height now, with me trying to measure it myself balancing and measuring, so probably not accurate), i have ordered a 4mm shim (although now thinking i need 6mm..) to fit between the clevis and the frame to make up for the shorter length. 

pics: 

35D2Syb.jpg

JYOISZO.jpg 

 

you can see the hose running off to the adjustment knob, its in perfect position for bolting to the subframe with a straight bracket, it fits perfectly! 

 

 

 

I will be installing a VFR1200 front end at the end of the month, so when that happens ill get the 6mm shim installed and check the sag etc

 

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On 31/03/2018 at 10:09 AM, manoil said:

Hi, This is interesting I was looking at the 1200 shock to replace my 6th gen 50k rear. But didnt find much info to help me decide so plumped for a new Ohlins STX which was going cheap at £300, just waiting for it to arrive from Italy.

But my son has a 5th gen with nearly 60k so waiting to see how yours feels on the road?

By the way whereaboots in Scotland are ye frae? I am from Paisley moved 15yrs ago.

 

I'm in Livingston, so not far away :) (although everywhere is "not far" in scotland :P)

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Yeah especially on a VFR.

Will probably try my shock on sons first see if it improves it then if it hasn't look at 1200 shock.

A 1200 Front looks interesting will keep tabs for your updates.

 

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20 hours ago, handkphil said:

Hi, what year VFR1200 shock did you use?

 

Thanks,

-Phil

 

Any VFR1200F shock will work, just not the 1200X (crosstourer thing) 

 

mine came off a 2010 bike

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Hey CraigG, how are you dealing with the VFR1200 front brakes. As you will know (or by now have found out) the VFR1200F forks require the calipers also from that bike. Their mount spacing is unique so NO other calipers can be used. How are you connecting them?

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Ohlins data:

 

VFR1200F: length 321.5mm, stroke 50.5mm, spring 1092-74 (1,028lbs)

VFR800Fi: length 325mm, stroke 58mm, spring 1092-59 (857lbs)

 

The shorter stroke could be an issue, but with a much stronger spring, maybe not...

 

Ciao,

 

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From my very rough calculations, you will get around 20mm shorter rear wheel stroke (100mm instead of 120mm).

Adding a few shims to bring up the shock length is not a problem and needs to be done so the rear doesn't squat, adding an extra 5mm would even be better.

But the spring should be spot on.

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On 10/04/2018 at 2:05 PM, BiKenG said:

Hey CraigG, how are you dealing with the VFR1200 front brakes. As you will know (or by now have found out) the VFR1200F forks require the calipers also from that bike. Their mount spacing is unique so NO other calipers can be used. How are you connecting them?

 

yep i am running the VFR1200 calipers (i had mis measured the caliper spacing an hoped to use some R1 calipers @130mm, but as you said, they are 126mm spacing),

I have drilled a hole through the piston wall to connect the two circuits (much like you would do for the VFR rear caliper delink) and i have got a couple of bolts to block off the extra line holes. so they will function as standard 6 piston calipers. 

 

I am using an 11/16th front master from a CBR600, which i calculate to offer the same braking force with all 6(12) pistons in operation as the VFR1200 M/C running the 5(10) pistons. 

 

 

I am really happy with the rear shock, its properly tightened up the rear end, even if its currently sitting low. I have both a 4mm and 6mm spacer to play with, although i think im going to run with the 6mm one

 

funny, i had suspected that it would around a 1000lb spring, but i didn't have any hard facts, i was working backwards from the bike's kerb weights (comparing VFR800, CBR1100XX and the VFR1200) i had spring rates for the VFR and XX, but not the VFR12. 

 

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22 hours ago, JZH said:

Ohlins data:

 

VFR1200F: length 321.5mm, stroke 50.5mm, spring 1092-74 (1,028lbs)

VFR800Fi: length 325mm, stroke 58mm, spring 1092-59 (857lbs)

 

The shorter stroke could be an issue, but with a much stronger spring, maybe not...

 

Ciao,

 

 

That's a shame. I have a couple of spare VFR1200 shocks I was hoping to use, but these days I'm looking for more suspension travel, not less, in order to provide some measure of comfort when navigating the appalling (and still deteriorating) UK road surfaces.

 

The solution would be to make some different linkage plates that would provide the desired wheel travel for the shorter shock movement. You could also then allow for the harder spring.

 

BTW, how do those shock lengths and travel compare to the 750 RC36?

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Those data are from various Ohlins catalogues, so they do not necessarily reflect the OEM, specs, but I would expect the stroke and length to be the same as OEM.

 

3rd gen: length 345mm, stroke 57mm, spring 1096-69 (971 lbs)

4th gen: length 324mm, stroke 57mm, spring 1092-79  (1,085 lbs)

 

Ciao,

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Interesting that the 3rd Gen is so much longer and although the sizes of the 4th and 5th Gen are so similar, the spring rate is even higher than for the 1200. I wonder what factors made them make those decisions.

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You may recall from our experience making the modified shock mount for my bike that the top mount on the 3rd gen is not the usual removable clevis used on many other Hondas, so the different length is probably just down to the different mounting method (stroke being identical).  The 3rd gen was a heavier bike, which would suggest a heavier spring rate, but it also may have been the result of fine-tuning on Honda's part.  However, these are not OEM spring rates, but simply what Ohlins decided to use on their replacement shocks.  Race-Tech used to have measured OEM spring rates on their website; not sure if they still do?

 

Ciao,

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Yes the different mount could explain the length difference. But as you say, the 3rd Gen is 5 kg heavier, yet it has a lower spring rate. Odd.

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The rear spring rate is not really weight dependent, its more linkage dependent. My ZZR project has an Ohlins that was to soft, but by changing the swingarm & the dog bones to match, the suspension is perfect now, but I never touched the shock. All down to leverage ratios.

 

YMMV

 

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9 minutes ago, Mohawk said:

The rear spring rate is not really weight dependent, its more linkage dependent. My ZZR project has an Ohlins that was to soft, but by changing the swingarm & the dog bones to match, the suspension is perfect now, but I never touched the shock. All down to leverage ratios.

 

Yes, that's true. Well, it's a combination of weight and linkages. The 3rd and 4th Gens did have different linkages. Not sure about the actual ratios, but they are the 'other way around'. The 4th Gen uses plates and the 3rd Gen uses a cast knuckle. I prefer the latter, but the former certainly makes it easier to adjust things, just by making different plates.

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