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PostPosted: August 10, 2009, 11:37 pm 
Benny_toe, I am happy to help!

The part that concerned me in your photograph was the bolt for the bellcrank pivot. It looks like the steel plates that hold the bellcranks has a simple through-hole for the bolt and I assume this is what the part rotates on? Maybe I just can't picture how you've assembled that part. The needle bearings should be fine although specific points of the needle bearing will be seeing huge loads. I decided to replace them with the old standby oilite sintered bronze bushing and the size I used is more than capable of handling the forces coming from the suspension. I purchase my bushings from http://www.mcmaster.com.

I've uploaded one of the drawings from my plan set that describes the parts in more detail.

Oh and I apologize for hijacking the thread. Maybe this should be split off into another post? Moderator? :)


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PostPosted: August 11, 2009, 12:11 am 
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Steve,

I don't see it as a hi-jack, we are still discussing the motorcycle shocks and pieces thereof.

The bell crank does not pivot on the bolt. There is a crush tube in the needle bearing. The plates are pinching the crush tube. The bell crank bearing is pretty wide but only 10MM in diameter.

I am wrong more often than I really care to admit and that being said I'm thinking the fulcrum bearing will take the load. That needle bearing certainly looks robust enough.

However, being warned I will take a much closer look at it tomorrow (build isn't at home). And I do have some 1 1/2" X .125" DOM on hand.

And many thanks for the heads up. Have enough problems without building them in.

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PostPosted: August 11, 2009, 11:31 am 
benny_toe wrote:
The bell crank does not pivot on the bolt. There is a crush tube in the needle bearing. The plates are pinching the crush tube. The bell crank bearing is pretty wide but only 10MM in diameter.


Did you use the needle bearing from the dog-bone that typically comes with this shock or how did you secure the bearing to the steel bracket of the chassis? I would love to see a photo of how you assembled that! thanks!

I find there is always more than one way to skin any cat, although I prefer to use a very sharp knife. :shock:

Steve


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PostPosted: August 11, 2009, 1:57 pm 
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I'll be at the shop later this afternoon and will take a few photos. I'll have to borrow a camera. Mine is unavailable until weekend after next.

The bearings are very similar to the dog bone bearings, just longer. The brackets themselves secure the crush tube (if that is the correct term) by basically pinching it. The crush tube is the interior bearing surface.

Hope the photos show what I'm talking about.

The R1 bell crank is a machined, one piece design not the individual pieces like the R6. I was impressed with it enough to give them a try. 8<)

Larrry


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PostPosted: August 11, 2009, 10:35 pm 
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sgraber wrote:
benny_toe wrote:
The bell crank does not pivot on the bolt. There is a crush tube in the needle bearing. The plates are pinching the crush tube. The bell crank bearing is pretty wide but only 10MM in diameter.


Did you use the needle bearing from the dog-bone that typically comes with this shock or how did you secure the bearing to the steel bracket of the chassis? I would love to see a photo of how you assembled that! thanks!

I find there is always more than one way to skin any cat, although I prefer to use a very sharp knife. :shock:

Steve


it's an actual OEM motorcycle linkage part, that has bearings installed from the factory.

it lives in front of the swingarm, this is a similar unit
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PostPosted: August 12, 2009, 12:39 pm 
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Steve,

What I'm using is similar to what Spam16v's picture shows. I think the big difference is what I have is one piece with the pivot bearing pressed in.

I took some pictures and I must apologize for the quality. It was a cell phone camera. Hope it makes calls better than it takes pictures.
Attachment:
IMG00123.jpg
Attachment:
IMG00124.jpg
Attachment:
IMG00125.jpg


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PostPosted: August 12, 2009, 2:24 pm 
Now that makes perfect sense! I really like that bellcrank and will need to get one to measure up. That would make my pivot assy so much simpler! We all learn new things, that's why I love this forum! :mrgreen:


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PostPosted: August 12, 2009, 4:09 pm 
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You have to keep an eye on eBay for those bellcranks. I just checked and didn't see any by themselves but check item #390080080472. The whole assembly for 10 bucks. Well that's assuming nobody else bids on it. They aren't high demand items 8<).

I bought 2 of the bellcranks alone and they were $10 and $12 + shipping. They're out there.

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PostPosted: August 12, 2009, 10:03 pm 
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Great information! It is good to hear from somebody with 15000 miles on bike shocks! Any idea what the ratio is on the stock motorcycle rockers?

Steve - Are you using the R6 rockers?

Kent


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PostPosted: August 13, 2009, 12:25 am 
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I'd be supprised if anyone can get the motorcycle bellcranks to give the right wheel rate. I tried but it wasn't even close. If your planning to try watch what years you get the shock from. Yamaha used the same spring rate on R6s over several years and model updates. However they changed the bellcrank from year to year. I don't know if they did the same with the R1. It is a great machined piece though.

Thanks for chipping in Steve. Motorcycle shocks are generaly high quality parts right off the bike, thus the good dampening qualities. I've found from playing with motorcycle suspensions over the years that it is more important to get the dampening right even if the spring rate is off alittle. It seems like most production cars install a "decent" spring rate but are way off on dampening. even the sporty ones.

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PostPosted: August 13, 2009, 10:31 pm 
The bellcranks are different across the years. I use the 2002 bellcranks and designed my suspension from scratch based around the 2002 MC damper/spring/bellcrank. It's a pullrod suspension acting on the upper a-arm. I don't claim to be an expert, in fact far from it, but my race engineer is a 30 year plus experts expert. He has gone over my suspension very detailed and finds it to be well matched to the bike shock and bellcrank. Honestly, because so many people on the 'Internet' keep trashing the idea of the MC shock I keep asking him over and over if he thinks I should switch to a traditional mounted coilover and he says nope. And actually it's fine with me if that myth continues because that means that these shocks will continue to be very inexpensive! So don't spread the word please! :roll:

Sorry I don't recall the exact ratio, I'll look it up and get back to you with the dimensions. Can anyone give me the dimensions for the R1 rocker with the built-in needle bearing?


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PostPosted: September 20, 2009, 8:56 pm 
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Does anyone have any experience with zx14 dampers?.

I just bought an engine from a bike wrecker that tells me he purchased 12 new zx14's to part out,can get 0 mile shocks for about $100 each.For that price and condition I'm pretty interested in trying them out.

Any thoughts?.


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PostPosted: September 21, 2009, 3:02 pm 
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Look up the spring rate for the ZX14 dampers to see. Sounds a bit shady that a guy will "buy" new bikes to part them out. He would be loosing his ass on those things.

Well i just bought 3 more of the bellcranks with the bearings off a R1 forum for $60. I got the 2007-2008 model as they have enough meat to drill anothe hole on both the shock side and pushrod side. This will allow for some adjustment beyond my street settings. i know its not optimum, but i have set them up for the wheel travel i need and calculated the springs i will buy from Hypercoil. I know the dampening wont be matched correctly... but they will do until i can afford to throw down big dollars on real ones.

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PostPosted: September 21, 2009, 3:35 pm 
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sgraber wrote:
...because so many people on the 'Internet' keep trashing the idea of the MC shock...

It's just math, and depends on: shock travel, spring rate, and the desired wheel rate on the car. If the car requires twice the suspension travel of the shock, the wheel rate will be 1/4 the spring rate, assuming a 100% installation value. The R1 shocks I tested had 1.5" travel and a 500lb spring, which will give 3" of travel but only 125 lbs wheel rate in the example above.

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PostPosted: September 21, 2009, 5:29 pm 
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Nothing shady,he buys the bikes minus engines and electrics from the t-rex kit car guys.They buy a dozen at a time and take what they need and then he does the same.

I'm in the same boat(as blue devil),just need to get the thing built on a budget and then fine tune from there.I figure I can add a sway bar up front to get the roll resistance needed with the bike dampers.I would prefer to be barless for the weight and that after many years of mucking with production based cars I'm convinced sways are the fastest way to make you slower.


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