[bullcrew]

DO you need an extra set of links?

I've been looking around and it seems the weakness on a Karpiel is the link plates.
Kurt and Henry came down today from the University (the have degrees/instructor level in mastercam and solid works as well as professors in machining and engineering) today to look at the link plates and pick up a few items we hard ano'd for them. I had them look at the links for production on a few sets for me and a couple of extra. Henry does work for the guy who races his DH wheel chair as well so he's got the 411 on what we put these things through.
They are mic'n and going to do a prototype with a little more material in a couple of places and run it through a program that works out the weak points due to leverage and stress points then design it.
It's going to be made of 7 series aluminum and I can ano any color, being that they are 7 series the finish will be shiny and glossy when done.
We are going to start with 10 sets of uppers and lowers after the prototype (which of course will be for me) and see how they sell, after that it will be runs for a couple of sets at a time depending.
I'm getting 2 sets originally the prototype and 1 more, so if anyone needs some please let me know.
Price will be dependent upon machining, we are shooting for a $290 price tag on the set of uppers and lowers. This is not a definative price only a guesstimate it may be lower, I am not making a dime on these it's straigh from the man. I'f intrest is there I'll post his name and number and anyone intrested can go directly through him.

 

[sanjuro]

Does it void the warranty?

 

[DHS]

there's already a guy that is doing this..

that is also selling new karpiel frames..

 

[TheMontashu]

Does it void the warranty?

What warranty? the head of karpiel is hiding somewere hoping he doesnt get his knee caps shot up.

 

[bullcrew]

there's already a guy that is doing this..

that is also selling new karpiel frames..

Yeah and if they were available don't you think I would have already bought them.
It's B's (HCM) friend mike I believe.
Last I heard they weren't available and mine are going to be 7 series which has a several thousand pound shearing point advantage over 6 series.

 

[lovebunny]

What warranty? the head of karpiel is hiding somewere hoping he doesnt get his knee caps shot up.

sar·casm (särkzm)
n.
A cutting, often ironic remark intended to wound.
A form of wit that is marked by the use of sarcastic language and is intended to make its victim the butt of contempt or ridicule

 

[Downhiller]

when you make/get them put pics....

i have on my army new one which is DHS taliking about..:
and on apoc. old one and i dontget the difrence..ink:

http://www.ridemonkey.com/forums/showthread.php?t=139509&page=2&highlight=karpiel

 

[seismic]

New links sound very interesting...looking forward for some pictures !

 

[bullcrew]

I'm getting mine done and a few extras, kurts going to sell the rest. I'm trying to find out the intrest level so I don't end up buying all 10 sets myself. I worked it like this: People are reluctant to ride the frames very hard due to the inability to get replacement parts. The links appear to be the only semi problem with that frame. Produce a prototype and I'll run it, produce a few extras identical out of the 7 series and I'll post them for you. If they don't sell I'll buy them.

Now I can use 2 sets maybe 3 but to have 10 is too much, I am just trying to get a feel as to the demand or people wanting an extra set for safety. I'll ano them any one of our 17 colors so they'll come in your choice of color it's part of the deal I worked out was doing the finishing.

 

[seismic]

Sounds very interesting !!! The next problem will be the day we need extra of the small cylinders which are inserted into the links and to which the lower shock mount is attached...

By the way...I think it is awesome that they will be avaliable in colors !

 

[bullcrew]

The next on the agenda given these sell will be the adjuster cams for seat and upper shock mount then the lower adjuster.
I'll have prototypes of these made for mine and if the need is there a little bit they will go into semi production.

 

[vitox]

bullcrew great job on that, just a friendly suggestion, see if you can get a quote for the links, without the eccentric thingy, and just have them use a few holes in the places that make sense, that would eliminate what actually makes the links fail, and not really eliminate any useful adjustability you cant replicate with a few mount locations.
my point is that the eccentric adjuster can in many ways be considered elegant or clever, they arent that useful, and (reason for the post) probably add cost.

 

[Brian HCM#1]

The original links never had a problem or any real weaknesses. There were a batch produced where the bearing pinch bolts were counter sunk too much. Those are still being replaced under warranty.

 

[vitox]

The original links never had a problem or any real weaknesses. There were a batch produced where the bearing pinch bolts were counter sunk too much. Those are still being replaced under warranty.

oh ive seen some that could make you think otherwise.

one thing though, i am not sure if "problem" might be the correct word since they do last a long time, but thats in the area where they fail when they fail, so if it drives the cost down, and makes is last longer, while not really being worse in any other sense, i would say its a win-win situation. thats just me though.

 

[bullcrew]

Not a bad idea, a 12 - 3 - 6 - and 9 o'clock position. That would eleviate any extra parts as well as give definative suspension travel 1 9" 2 10" and 1 11". I'll take it into consideration.
Good idea.

 

[seismic]

The next on the agenda given these sell will be the adjuster cams for seat and upper shock mount then the lower adjuster.
I'll have prototypes of these made for mine and if the need is there a little bit they will go into semi production.

Very good idea with making some spare parts for the Karpiel....I will be interested in alsmost anything set into production ......I mean, this is the chance to get some quality parts for the frame

Looking forward - I trust you will keep us updated

 

[Dugger43]

I'm looking forward to seeing what you come up with. It's great to have professors and engineers getting involved in keeping our bikes updated. It seems like there are quite a few people desperately looking for links (and other parts) for Army's...

This desperation for replacement parts has led me to come out and expose myself. I hate to see my fellow Karpiel riders cringe like this, so for those who can't wait, I do have a few army links available NOW. (Clear anodize only). Quantities are limited right now, so it is first come, first served, but I will eventually make more. Also, bullcrew and his guys should have some interesting new stuff "soon".

They are sold in complete sets as this insures a tight fit. A Set will include upper and lower links w/ enduro-max bearings as well as the barrels and a new shock bolt. Bullcrew, I suggest you have your guys do the same. Old worn barrels will tend to slip in new links and people start getting bummed. Otherwise, just do the hole drilling thing as noted above. Not only does this eliminate a component but it also reduces machining time.

I have some upper cams as well. blue, black, red, and clear. I'm not doing the distribution so contact Brian. He'll hook ya up.

 

[vitox]

hey dugger, any chanche you could machine me a set of swingarm yokes with a different pivot bore?

 

[kidwoo]

hey dugger, any chanche you could machine me a set of swingarm yokes with a different pivot bore?

Heh heh.

Tryin to make it pedal better eh?

 

[DHS]

that very good to hear and see.

 

[Thrillkil]

I just got a set of screw in upper links from Brian probably 3-4 months ago. How much for just lowers for my Disco?

 

[seismic]

Well, I love my custom steel links and even though I think they are indestructable I think I wil try a set of the new links when they come out !

 

[seismic]

.......wonder if this thread is going to develop into "the Karpiel thread".....yeah, ok - dont fry me for that comment

 

[bullcrew]

I actually thought of having him machine me a set from Titanium, It would be the same initially.
Those links look good, make em .5 thousands over and I'll ano them.
I talked to Kurt and he said he'd look into placement for the 4 holes.

 

[bullcrew]

I do have a few army links available NOW. (Clear anodize only). .

What series aluminum?
And
how much?

 

[Thrillkil]

I actually thought of having him machine me a set from Titanium, It would be the same initially.
Those links look good, make em .5 thousands over and I'll ano them.
I talked to Kurt and he said he'd look into placement for the 4 holes.

out of curiosity, how much would the billets cost to machine a set of TI links?

 

[vitox]

Heh heh.

Tryin to make it pedal better eh?

nope

i designed a new pivot and modified a swingarm to make it fit but i started with a trashed swingarm with the pivot bores a bit flared out so its never going to work quite well and i want to put it through some abuse to see if the system is as good as i think it is. it should cure most all problems associated with karpiels very ingenious and light self-healing (and self slopifying) pivot design.

 

[bullcrew]

out of curiosity, how much would the billets cost to machine a set of TI links?

Kurt mentioned doing a set of 1 off TI for me just because he can. I like people who get excited, they do extra.
The only question I have to it is the flex, I know ti flexes more than standard steele but how is it's rigidity compared to 7 series as far as flex and wobble in that length.
There's been the big debate of ti bolts over standard steel and they are small in comparison. I'll call him or Henry today to see what there thoughts are on it, I'd be curious just to find out if nothing else.

 

[wirly]

nope

i designed a new pivot and modified a swingarm to make it fit but i started with a trashed swingarm with the pivot bores a bit flared out so its never going to work quite well and i want to put it through some abuse to see if the system is as good as i think it is. it should cure most all problems associated with karpiels very ingenious and light self-healing (and self slopifying) pivot design.

I'm replacing my old rear triangle with a new one. The old one is fine except for a dent in one of the chainstays (or was it the seatstay?). I was going to keep it as backup, but if you want it for mods I might sell it "cheap".

 

[kidwoo]

nope

i designed a new pivot and modified a swingarm to make it fit but i started with a trashed swingarm with the pivot bores a bit flared out so its never going to work quite well and i want to put it through some abuse to see if the system is as good as i think it is. it should cure most all problems associated with karpiels very ingenious and light self-healing (and self slopifying) pivot design.

Sounds cool. I'd like to see what you come up with.

 

[Thrillkil]

Kurt mentioned doing a set of 1 off TI for me just because he can. I like people who get excited, they do extra.
The only question I have to it is the flex, I know ti flexes more than standard steele but how is it's rigidity compared to 7 series as far as flex and wobble in that length.
There's been the big debate of ti bolts over standard steel and they are small in comparison. I'll call him or Henry today to see what there thoughts are on it, I'd be curious just to find out if nothing else.

Titanium, if you use the same amount of material as an aluminum link, will be stronger and stiffer than 7-series aluminum, but will actually have a weight penalty over aluminum. If you were to remove more material than an aluminum link, I am not sure what would happen. Done right, you could probably make a link that is lighter and stronger than aluminum, but some fancy footwork would be required to make it as stiff.

 

[vitox]

Sounds cool. I'd like to see what you come up with.

its very simple actually, i dont know if its a commercially viable solution but what i did was to insert a very large needle bearing "cartridge" thingy in where the plastic bushings go, and machine a rather expensive steel, hollow 20mm diameter axle. figure it to be quite similar to a boxxer front axle only the endcaps go where the original bearings were. its got the see-thru pivot factor like the session has, but each pivot adds 50g over the original design unless i can determine that its safe to go with less material in the axle.

 

[kidwoo]

its very simple actually, i dont know if its a commercially viable solution but what i did was to insert a very large needle bearing "cartridge" thingy in where the plastic bushings go, and machine a rather expensive steel, hollow 20mm diameter axle. figure it to be quite similar to a boxxer front axle only the endcaps go where the original bearings were. its got the see-thru pivot factor like the session has, but each pivot adds 50g over the original design unless i can determine that its safe to go with less material in the axle.

Screw this US revival crap, you should be making these things.

Sounds waaay burlier than what Jan did. Good Idea.

 

[Thrillkil]

its very simple actually, i dont know if its a commercially viable solution but what i did was to insert a very large needle bearing "cartridge" thingy in where the plastic bushings go, and machine a rather expensive steel, hollow 20mm diameter axle. figure it to be quite similar to a boxxer front axle only the endcaps go where the original bearings were. its got the see-thru pivot factor like the session has, but each pivot adds 50g over the original design unless i can determine that its safe to go with less material in the axle.

That sounds like a really good idea - seems like it would reduce the stress on the bearings, and make 'em last longer

 

[Dugger43]

What series aluminum?
And
how much?

The links I made are machined from your standard 6061-T651 aluminum. 7075 is a far superior alloy and machines beautifully. However, given the exceeded cost and the amount of strength that is actually needed makes it tuff to justify making them from 7075 . I'll get a price quote on some matrial and see how much more expensive it really is. Now if these were landing gear parts for a Boeing 747 jumbo jet then I would defiantly use 7075 aluminum. And as far as cost is concern, check with Brian. It should be about the same as what you were looking to get.

 

[Dugger43]

hey dugger, any chanche you could machine me a set of swingarm yokes with a different pivot bore?

Cool concept.. All the yokes I have are already bored out. If you need to go larger on the diameter, I might be able to help you out.
Check out: http://www.fairing.com/CDData/Frame depot Content/Frame-depot-content.htm
They may have just what you need...Straight from China.


Whohoo 5 postings! When do I get my monkey status?

 

[vitox]

Cool concept.. All the yokes I have are already bored out. If you need to go larger on the diameter, I might be able to help you out.
Check out: http://www.fairing.com/CDData/Frame depot Content/Frame-depot-content.htm
They may have just what you need...Straight from China.


Whohoo 5 postings! When do I get my monkey status?

hmm i think you are 45 postings away....

yes actually bore diameter is 26mm, see if you can spare a couple and send me a message with the cost?

 

[vitox]

That sounds like a really good idea - seems like it would reduce the stress on the bearings, and make 'em last longer

maybe it does that but that wasnt the idea behind the design, after several trips to the machinist to make new axles and also after a friend of mine (the guy who got a WC top 10 on an army) broke a pivot axle in his race run at the kaprun worlds, we started seeing how to improve on the original system.

i talked to jan about it (and the system i was prototyping) and it turned out the system we all know was an adaptation of his original idea that. hence the a bit funky setup. originally the bikes used the plastic inserts as a bushing properly, and had a huge thru axle that rotated inside these yellow plastic things. massively stiff and light but absolutely exposed to dust and not useful therefore.

so the idea behind it all is to avoid the part of the whole pivot that has the smallest diameter (patineto where are you we need the technical term for this), ie: the "nub" where the bearing presses in to, thats the part of the axle that bends after serious use, or can break off.
i havent tried it enough to see if the added stiffness in the link/axle part makes the original "stabilizing" effect of the yellow plastic ring, useless or not, but im sure that with better alignment those frames would not need the "self aligning" and sliding axle principle they have.
next up would be a way to make both upper and lower links stiffer and more exactly separated with a bridge.

 

[patineto]

Screw this US revival crap, you should be making these things.

Sounds waaay burlier than what Jan did. Good Idea.

That sounds like a really good idea - seems like it would reduce the stress on the bearings, and make 'em last longer

you see mister Vitox.....

you are the man go at it, your ideas are always sound and Inovative, looks like you need to start to explore the territory of the "makers" as oppose to the tuners..

remenber with the wide spread of shipping companies, the fact that you live down there in Chile makes very little diference..

if you need US manufactures (highend aerospace shops, i work with let me know) or i also have contacts "Over seas" if you want...

i'm sure you ideas will have a great impact in the development of the suspension bikes since you are really down to earth but still have your eyes looking to the stars.

whatever I can help let me know...


Your Gruppy Ricardo

 

[Thrillkil]

Brian HCM1 is the guy to talk to. There have been a few new complete Armageddon frames put together recently, so I would guess a new swingarm is not out of the question.