K2 / Proflex Riders Group
General => Tech Forum => Topic started by: 856GT on September 26, 2006, 03:02:26 am
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so its ten years since i bought my first 856 and i am now the proud owner of my third frameset.
I used to ride a medium and earlier this year i got a large one from ebay, which suits me better these days.
i have just purchased another large frame (mainly for its shock and disc brake mount) but it is different from my other large one.
the original large frame i got has a gusset on the downtube, behind the headtube, which my first 856 (medium) doesnt have. I thought perhaps it was only added to the larger frame size but this new large one doesnt have it either. does anyone know why they differ? did proflex make different versions of the 856??
the other problem i am having is with fitting the shock. i just took the astro 5 shock off the large frame without the gusset and tried to fit it on the large frame with the gusset... and it wont fit properly! - i can bolt it on OK and everything looks right - until you try to adjust the lever on the shock and it hits the seat tube!
can anyone tell me whats going on??
i also understand that the Astro 5 requires a 'freedom plate' for fitting to an 856. i am not sure if what i have includes one, so i would be very grateful to anyone who could post up or email a picture of it so i know what to check for.
many thanks!
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I think we need pictures................
I'm not aware of 856 frame sizes being significantly different in design.........except maybe the small?
The only differences on some 856's is the hole through the seat tube for canti brakes on older models and some extra welding on later models (XP-X) to strengthen them, but I can't imagine any of these welds looking big enough to be considered a gusset?
What do you mean by "a gusset on the downtube behind the headtube" ??
Do you mean the flat plates that support the seat tube "mast" to the bent seat tube that connects the bottom bracket to the top tube? (probably no better explained than you did.....<grin>)
Col
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What do you mean by "a gusset on the downtube behind the headtube" ??
Do you mean the flat plates that support the seat tube "mast" to the bent seat tube that connects the bottom bracket to the top tube? (probably no better explained than you did.....<grin>)
Col
Thanks for reply Col!
It's not like the plates either side of the top tube / seat tube junction -it's basically like a quarter circumference piece of tubing, a few inches long, welded flush on the underside of the down tube and butted up against the headtube. It is a common feature on many frame designs - i am just confused as to why there is this difference between two otherwise identical frames. having said that, there must be some difference because the shock fits one of them perfectly (without gusset) but doesnt on the other.
what's the best way to post pictures on here - can i attach them into the thread?
cheers
Tom
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our gallery is down at the moment and our files section is disabled thanks to a$%#@ hacker.You might have to find a "free image hoster.I cant begin to imagine that two 856s would be so different.if you have a 856 fitment risse havent you already got a freedom plate?Its a oversized washer on the bottom.I would say 6mm thick and of a very similar dia to the shock at the end.It creates a flat surface over the top of the cone depression in the strut,which the x55 strut didnt have..You can post a pic by wrapping a url in {img}your url{/img},but it already needs a home on the web.(use [ brackets instead of the { in the example)
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imageshack.us is a nice easy place to host pics :)
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Thanks fellas...
I will try and get some pictures up somewhere.
It seems i didnt get the freedom plate with the shock and frame i just bought :(
as it is, the bottom part of the shock (that the air valve sticks out of) is bolted directly to the strut with no washer of any sort.
does anyone else have this gusset thingy on their downtube? - i am beginning to think there is something strange about the frame i have with it - its also the one that the shock wont work properly on
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Hello Laaandaaan! Concrete Cows here!
Great! I think I'm with you now!
The issue of the rear shock not fitting is nothing physically to do with the "gusset" right? because the gusset is on the front of the bike....! On the underside of the downtube where it meets the headtube, Yes? (Doh! exactly as you originally described it - I am thick).
In that case it's fine and perfectly normal.
Later editions of the 856 frame were strengthened in several places where the welds had (occasionally) failed and resulted in warranty claims. This is one of these and doesn't interfere in fitting anything to the bike, right?
I've got a Medium XP-X which is a special edition 856 only sold in the UK to use up the last frames off the production line. I thought only the XP series bikes (XP-6, XP-8, XP-X) had this extra weld (and some more welds in other places).
I think there's also additional welding around the rear pivot box on the frame, but I'm not sure as I don't have an "old" 856/855..................yet. What's your other ones like?
Interestingly enough, my medium 857 does not have this additional gusset weld and yet the frame design is virtually identical, except the pivot point was moved. Theoretically, my XP-X might even be newer than my 857 as they did run in parallel for a while.
What is your bike badged up as? i.e. the frame titles?
i.e. Does it actually say 856, or maybe "Beast" or anything else?
Basically I think you've got nothing to worry about, if anything it's the stronger version of the frame than the earlier 855/856 versions.
Pro~Flex must have beefed these up for us British because we're so much more extreme riders than anyone else in the world....................(waits for howls of derision from the rest of the forum)............
Unless anyone else in the world has got a "gussetted" 856 ?? replies please?
actually I think that sounds like a bit of sexual innuendo, doesn't it? Phnarrr, Phnarrr!
Col.
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Hello Laaandaaan! Concrete Cows here!
;)
Great! I think I'm with you now!
The issue of the rear shock not fitting is nothing physically to do with the "gusset" right? because the gusset is on the front of the bike....! On the underside of the downtube where it meets the headtube, Yes? (Doh! exactly as you originally described it - I am thick).
:)
spot on mate... its nothing to do with the shock i just thought it might indicate a difference between the frames.
Later editions of the 856 frame were strengthened in several places where the welds had (occasionally) failed and resulted in warranty claims.
Basically I think you've got nothing to worry about, if anything it's the stronger version of the frame than the earlier 855/856 versions.
:) :) :)
Pro~Flex must have beefed these up for us British because we're so much more extreme riders than anyone else in the world....................(waits for howls of derision from the rest of the forum)............
lol !!!
all three of my frames have 856 livery (the two i will keep are both imo the nicer 'titanium' paintjob with white graphics.)
If you are interested in getting your hands on an 856 i will be selling the large red frame i have just bought, with a virtually unused and mint condition ODS shock, sometime very soon.
thanks to those that have replied - i am getting much closer to solving my confusion! next step has to be to find a freedom plate and get that fitted.
...though i still cant work out why i was unable just to swap the shock and strut between two same sized frames without this problem of the adjustment lever hitting the seatpost.
Is there a right and wrong way up for the strut fitting?
Tom
aka (dj)GT!
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i am 99 percent sure the struts are symetrical.There must be a difference somewhere though if the risse fits on one bike and not the other.The bigger frames may hold the strut out and up compared to the smaller bikes.The freedom plate adapter is available from risse.I will see if i can get some pics up too,i havea risse terminator on my 756 with freedom plate adapter.