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Discussion Starter · #21 ·
That's awesome.There is always more than one way to do things.
I'm not sure how long the nylon bushing will last,keep us posted.

Now that I have put a total of 3700km on my bike,probably about 3000 with improved suspension,I think I want to lower the front compression damping a little bit.I put in the heavy springs at 2 turns and 20W oil.I have the rear shock set to recommended base settings for the R6 and have not felt the need to change anything except preload.Once I adjust the front I will start to play around with the rear settings.
 

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I'm not worried about the nylon wearing out; it's plenty strong in compression. Also, an appreciable fraction, if not most, of the load is being borne in shear by the clamping force of the nut and bolt flange on the sides of the shock mount. I didn't and wouldn't tempt foregoing them, but I also wouldn't be surprised if the spacers proved to be unnecessary.

I was able to finagle my fixie lockring spanner in and backed the preload off to notch #3 from #4. The ride height now feels exactly as it did before. The most noticeable difference so far from the stocker is that it no longer snaps out of turns violently the way it used to. It was never a cause for concern, but it always felt like it wanted to highside me if I came out of a sharp turn too abruptly.

Funny you mention not playing with any of the knobs after all this time. I haven't played with any of the damping settings on my cartridge emulators in 16,000 miles either. Having to open the forks and retrieve them is certainly a barrier to tampering, but it is a little bit silly to go to all this effort to replace non-adjustable suspensions with adjustable ones, and then never bother adjusting them! Of course, I'm not a track rider looking to shave milliseconds off my lap or anything of that sort, just a daily commuter/tourer looking for better safety and comfort. Not that good traction is any less important therein, but they are lower hanging fruit being generally usage modes that don't entail riding at 99% 100% of the time. And really, the most important thing that these upgrades offer is not all the knobs , but the innately superior damping curve over any sort of fixed-orfice suspension.
 

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Fantastic!! Thank you Thasiet for digging into this a bit further. The frame grinding was the thing keeping me from doing this. I won't keep this bike for too long and hated the thought of a selling molested frame, even a little as the OP did. Even the JRi required a small bit of grinding. Next project! I am loving the Gold valves and RT springs already.

Brad
 

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Discussion Starter · #25 ·
Wow cool modification you made there, so hows the handling and performance after installing it?
FANTASTIC!
HUGE improvement in control AND comfort.
 

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Yup. One month in I'm having no issues and am loving the better cornering precision and comfort. This morning I dragged my (LOWERED) footpeg all the way through a cloverleaf freeway interchange :D $70 and one day wrenching for a nitrogen-charged, four-way adjustable shock is completely worth it!
 

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Discussion Starter · #28 ·
How are you guys (and with what material) sleeving the lower mount to match the CBR's linkage?
I found a piece of steel pipe that had almost the correct OD then carefully drilled the ID to correct size.Took me a couple of tries because you're left with a wall thickness <1mm.
 
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Discussion Starter · #29 ·
You both (I think) swapped the top yoke using the CBR shock top mount on the R6 shock. Is the bolt (and holes) diameter the same on this end?
Yes,the CBR upper mount simply bolts on.
 
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Amazing thread.. Props to powertoweight and Thasiet !!! Much appreciated. I might be trying this before an exhaust thanks to my non abs model.


Remind me: I searched very hard through google even though I swear I read on here-> Is there a reason we can't swap out the front forks from a cbr600rr or r6? Diameter comes to mind. Our triple tree or whatever is too small.. But could it be bored out or swapped?

You'd need new clip on's too I guess? Unless it is major fabricating, I think the idea should stay on the table.. Like this one (r6 rear)
 

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Discussion Starter · #33 ·
Is there a reason we can't swap out the front forks from a cbr600rr or r6?
From what I have seen elsewhere,sometimes the easiest method of retrofitting forks from another bike is to change everything including the triple clamps and steerer tube and bearings,along with axle,brakes and wheel.
Obviously the bearings have to be made to fit the frame head tube.

A very good question and something to ponder over winter.I like my Racetech springs and emulators but they do leave a little to be desired.
I would want to also retain ABS which would require a tone ring and wheel speed sensor.
 

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Discussion Starter · #35 ·

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Well let's find out how they do it.
Lol.. you heard the man^.

I'm not bike assembly saavy yet, but steerer tube and bearings sound somewhat of a big set back.

Also, I'm curious about the chain and wheels. Are the new wheel sizes going to change the 250 handling? (Better tire selections right?)

I stumbled across that white cbr, that sparked my interest in the idea. I like the gsxr-esque hid headlight and those dual rotor front brakes would be nice.


Right so.. back to comparing dimensions to find the supersport counterparts. Looks like 600rr parts minus those gold r6 forks.
 

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Ive got an idea,
lets put a 600 swingarm in, then we'll need a 600 frame, and the engine wont fit, so we'll need a 600 engine, and the bodywork to to go with it....

hang on
 

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I am just thinking that tapered bearings in the steering head would go a long way to improving the front end.
I seem to remember a conversion kit being available for a CB200 that I had in my garage for a while.
I know it was a very easy change on my BMW /2 frame that I used to build a sidecar rig.
Before 1970 BMW used ball bearings in the steering head. After 1970 they used tapered rollers.
I was shocked when my nephew took apart the front end on his GSXR600-something and there were steel balls in a NYLON race!

But for me, on this bike, I think the R6 shock and (eventually) Race Tech parts in the front fork will do me just fine. But then, I'm not a racer, I am just a commuter that is trying to restore handling since adding a poop-load of dead weight in the form of Givi.
 

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for the second installer of the R6 shocks .
please post pictures of the installation. would be helpful.;)
Sorry dude; I posted every photo I took. The standard shock removal process is photo-documented in the shop manual, which you will want to have on hand, and my write-up touches on all deviations I made from the scheduled flight path.

To all: let's please keep to the topic here. This is a technical thread about how to adapt and install a cheaply available, high quality, but non intended rear shock into our bikes. Talking about tapered bearings, USD fork swaps, and supersport envy / supersport disdain belongs elsewhere.
 
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