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A Cheaper Rear Shock upgrade


EVLXX

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Well like most everybody here that rides the XX... at some point in time I found myself wanting a little more out of my Rear Shock.

So what to do..... One option was to spend $1300 on an after market Ohlins or Penske. Um NO thanks... that's a lot of dough for this guy..

So.... maybe there is another way.....

After a boat load of searching, a lot of figuring, and a little bit of elbow grease...

I now have a..... Fully Adjustable Rear Shock.

It has...

High and Low speed Compression Dampening (Cool), Rebound Dampening, and Hydraulic Pre-load adjustment (Super Cool)

It's a 2009 Yamaha R1 Rear Shock.... with a few extra made parts to get it in the XX.

My Total cost.... is still pending.... I'll list it all at the end when I'm done building this post.

Out with the Old... In with the New.... My XX on top... above the R1 going in....

post-726-1316432420.jpg

I plan on adding more pictures and How to do's, and where to buy's, a little later.... so check back for more information later.

So first order was to get the correct spring rate. Original R1 on the left... new on the right. I have a 18kg (1000lbs./inch) spring on my XX. So since I'm not changing any of the pivot points and linkage.. I still need the same rate spring on the new shock. But there's 2 problems here. 1. The stock R1 spring has an inside diameter of 2.125", and nobody sells those of the shelf. So I looked into having a custom spring made, which would have cost $150 and taken 2-3 weeks to get. -or- 2. I could buy an off the self 2.250 spring and then have some adapter collars made to make it fit correctly.

Since option 1 was going to take too long, I went for option 2. But this also posed a second problem. The stock R1 spring is 6.380" long. Why... because the pre-load adjuster only has a 0.300" range of adjustment. So this means that the spring has to have almost all of it's pre-load built into the springs free length. So after carefully measurering the pre-load on my current XX spring... I called on our resident wizard and asked him to make me some special collar adapters. He agreed... and I orderd the new 6" spring from here...

http://www.hrpworld.com/index.cfm?tpc=Hype...;action=product

I got the spring in 3 days.... and it didn't cost me $91 like the website said... I believe it was more like $89 after shipping...

(makes me wonder why anybody would want to buy shock springs from Racetech for 50-70% more....)

post-726-1316605452.jpg

Spring adapter collars... Made by None other than... "STAN".

I gave him all the measurements and, well what do you expect, Yep Perfection !!!

post-726-1316519509.jpg

New Top Mount...

Another small problem was that the new shock is too short, so.... I knew I was going to have to make a longer, and beefier top mount to make up the difference, but how big and how long??? Good question, especially since I didn't have the R1 top mount. Oh well, once again after taking a lot of very good measurements, I arrived at the new dimensions, from the center of the eyelet to the top of the mount I needed exactly 59mm in order to make the R1 shock match the Stock XX length.

It just so happens that I had a piece of 1.5" x 3" bar stock laying around, so after a few HOURS with a drill press, a band saw, a cutting torch, a 7" grinder, and a 4 1/2" flapper wheel grinder.... I had my top mount.

post-726-1316519510.jpg

A look at the location...

post-726-1316519513.jpg

So it was obvious I was going to have to make room for the new shock reservoir,

post-726-1316605608.jpg

Which meant finding a shorter battery with the same CCA. (or close enough) Well once again after some more searching, I found a battery that was 2" shorter and still has 190CCA. The one I was removing had 210 CCA. Close enough in my book.

post-726-1316605633.jpg

Now I had to make it all fit....

I figured I need to shorten the battery box by at least 1.750" (1 3/4"), and if I rotated the bottom around 180 degrees so that the drain would be in the back , instead of the front, it would give me that just that 0.250" more....

post-726-1316605661.jpg

Fun stuff,

I like plastic welding, I even like to make it stronger than it was, especially in this case, where the last thing I want to happen is to have my battery fall down onto my back tire while I'm riding down the road.... that would suck.

So... with a little wire mesh.... "specifically cut on a 45 degree lay out pattern".... I feel more than confident about this job.

post-726-1316605678.jpg

Short-er... and strong. Ahhhh.. it's a beautiful thing.... kinda looks like a little tool box tray now. Haha.

post-726-1316605687.jpg

So then there was this small problem with the Bottom eyelet width. The XX shock is 14mm wider than the R1.

post-726-1316644913.jpg

But the beautiful thing is, the sleeve is exactly the same diameter, so it's a slide in affair.

post-726-1316644925.jpg

So with a couple of make shift spacers to keep it centered on the shaft... it's good to go.

post-726-1316644938.jpg

So with everything up to this point figured out... I Installed the shock, and added the correct shims to the top in order to get the correct ride height..... and and .... it was a perfect fit.

There's about 3/8" gap between the reservoir and the Battery box, and all of the adjuster are very easy to get at. I Love it.

post-726-1316644955.jpg

So.... over then next to days of riding it back and forth to work... my excitement slowly went down hill. The more I tried to get the shock adusted propperly, the more I was dreading what I had feared from the start.

The Stock R1 internals can't handle the 75% stronger spring.... Compression and Travel are fine, but there's just no slowing down the rebound.

So.... it's off to Moto-Pro in Washington to get re-valved.

http://www.moto-pro.com/Services.asp?strMPSID=SHOCKREVALVE

The guys name is John, and he says that its a great shock, even after I told him of my lack of excitement over the new cost increase of my project, he told my that I was still on a great path, even remarking that the end result will be as good as an Ohlins or Penske..... just a lot cheaper.

So what are my costs up to this point....

R1 shock off of Ebay shipping included.... $74,

New Spring...........................................$86,

Collar Adapters..............................$Pending,

New Battery.......................................... $86,

Projected Re-valve + shipping...............$290, (ouch)

So... projected final cost is roughly.... $536.

Not bad.... I guess..... (not as economical as I had hoped for when I started all this, but).... not bad.

I guess we shall see..... next week, when I get the shock back.

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So what to do..... One option was to spend $1300 on an after market Ohlins or Penske. Um NO thanks... that's a lot of dough for this guy..

....

I plan on adding more pictures and How to do's, and where to buy's, a little later.... so check back for more information later.

I shall watch and wait.

I replaced the rear shock last winter with a slightly-used XX shock from another board member. Just to have the stock one rebuilt was over $300. Unless I'm doing track days, I couldn't justify over $1,000 for a shock. :icon_eek::icon_frown:

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Oh damn, Eric. This is good news. Should I rush right over to ebay and start loking for the R1 shock right now before all the other xx owners push the price up? Did I say that out loud?

Very much looking forward to what you have come up with explained in simple terms that a simple man such as I can understand.

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About 2 years ago I read a write-up on how to fit a 2000-2001 CBR929 rear shock into my VFR800, so I picked one up that looked brand new off eBay for $20, created a spacer from the building supply section of Home Depot and installed it.

The difference was actually pretty significant.

So since the Gen 1 VFR800 and XX are so similar, I wonder if the same shock would fit there too. I will admit that the R1 shock looks cooler :icon_biggrin:

The one I got looked exactly like this:

cbr929shock.jpg

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For those that have wondered about the spring rate... I replaced the spring with the correct sized Spring....

For the rest... who are patiently waiting.... 2 things... 1. BBC Top Gear is on in 1 minute... and 2. I'm still playing with the compression and Rebound dampening setting, to make sure this will all work, Correctly, before I go advising anybody else on the subject.

Thank You.

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You are going to send me to the freaking poorhouse I swear!

Looking forward to seeing the exciting conclusion to the shock saga!

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It will be interesting to see whether there will be enough compression and rebound dumping .Shock in XX ( and some other Hondas ) has unusually short stroke , 52 mm , Yamaha is in 65 mm range . Obviously for given rear wheel movement shock travels less in xx vs R1 and on the top of that Yamaha is 100-150 pounds lighter . Insufficient valving might be an issue .

Adjusters only can lift or lower the dumping force vs velocity curve , they cannot change the shape or angle of it .High speed adjuster like in R1 changes the preload of the shim stack

I would also check what happens when R1 shock bottoms , obviously with longer stroke the rear wheel might be hitting something .

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Insufficient valving might be an issue .

Correct.....

and it is.

It was really simple really, when going from a 11 kg spring, to an 18 kg spring.... one would automatically assume there might be problems, and there is.... soon to be was.

Stoke is fine...

Compression Dampening is fine...

The problem was Rebound.

When you install a spring that's 65-75% stronger than the original unit... it just can't slow it down (control it) enough.

So re-valving is in order.

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Just to have the stock one rebuilt was over $300. Unless I'm doing track days, I couldn't justify over $1,000 for a shock. :icon_eek::icon_frown:

Hence why I went down the road I did...

and even though the end result is going to cost me about twice as much as having the stocker rebuilt, I know it's going to be worth it....

There's NO Comparison to having your shock Adjustable, to a Non adjustable stock unit.

I mean lets face it.... after this is all done, I'm going to be able to add 200lbs. or remove 100 lbs. of pre-load to my rear shock in under 30 seconds.... How Cool is that ???

Very much looking forward to what you have come up with explained in simple terms that a simple man such as I can understand.

Is the above simple enough ???

Watching this thread.

I'm at 50 K and could use a good rear shock.

But I don't have the set up skills.

I know a guy that's going to have a stock XX shock with about 27K miles on it and a 1000lbs Hyperco spring on it for sale cheap. :icon_biggrin:

You are going to send me to the freaking poorhouse I swear!

Looking forward to seeing the exciting conclusion to the shock saga!

I'm not trying to send you to the poor house..... my aim was to help you stay out of it.

Found this chart when looking for a replacement for my GF's GSXR-750

Those are some awesome charts..... Thank you very much for posting them. I like them.

What a great write up. Very interesting and I love that you are not afraid to give it a shot.

Thanks, although.... let me just add, my only Fear was this was going to cost me more than $350.... which it now has.

But I'm sure I won't be complaining about that for long. :icon_twisted:

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Part of the reason I went the 900RR shock route which was done originally by Carlos on the old board I believe and copied over onto OzBB back before I joined in 06 :icon_think: I to had the problem of the springs being different, I went with a 6'' x 2.25'' 1100lb Eibach spring and as above needed a collar spacer made up as the stock spring tapers and is ~6.5'' :icon_think: Made a huge difference and cost me ~$460AUD back when our $AUD was ~US.75c :icon_surprised:

A new Öhlins then was ~$2k AUD and a Penske ~$1500 :icon_eek:

I got the collar made and the shock rebuilt but not re-valved, it's done about 70000km's now and is feeling a bit tired so am going to get it freshened up and will look at getting the valving altered a bit as well because it always felt like it kicked back a bit on sharp bumps :icon_wall:

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so the hyperpro spring will work? with the spacers that stan made.

I know a guy that's going to have a stock XX shock with about 27K miles on it and a 1000lbs Hyperco spring on it for sale cheap. :icon_biggrin:

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so the hyperpro spring will work? with the spacers that stan made.

I know a guy that's going to have a stock XX shock with about 27K miles on it and a 1000lbs Hyperco spring on it for sale cheap. :icon_biggrin:

I'm a little confused by your post... but I'm also not fully awake yet either...

But I'll try to answer....

ON the R1 shock...... Hyperpro spring will work, but only with the spacers that Stan made.

On the stock XX shock... a 8" Hyperpro spring will work, with the addition of a 1" spacer, both of those bought from http://www.hrpworld.com/index.cfm? , Then you also have to buy 3 adapter plates from Race-tech.. http://racetech.com/ProductSearch/2/Honda/...100XX/1997-2003 , In the end you'll have a stock Shock that works much better for about $160 after shipping.

As for the guy with the Stock XX shock with the 1000lb. Hyper spring already installed.... That would be ME, as soon as I get this R1 thing figured out, and as far as CHEAP.... I'll be open for reasonable offers. (I just put the Hyper spring on it 2 months ago)

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so the hyperpro spring will work? with the spacers that stan made.

I know a guy that's going to have a stock XX shock with about 27K miles on it and a 1000lbs Hyperco spring on it for sale cheap. :icon_biggrin:

I'm a little confused by your post... but I'm also not fully awake yet either...

But I'll try to answer....

ON the R1 shock...... Hyperpro spring will work, but only with the spacers that Stan made.

On the stock XX shock... a 8" Hyperpro spring will work, with the addition of a 1" spacer, both of those bought from http://www.hrpworld.com/index.cfm? , Then you also have to buy 3 adapter plates from Race-tech.. http://racetech.com/ProductSearch/2/Honda/...100XX/1997-2003 , In the end you'll have a stock Shock that works much better for about $160 after shipping.

As for the guy with the Stock XX shock with the 1000lb. Hyper spring already installed.... That would be ME, as soon as I get this R1 thing figured out, and as far as CHEAP.... I'll be open for reasonable offers. (I just put the Hyper spring on it 2 months ago)

Thanks Eric, Gotcha! And i'll wait for the finished result.

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