Carbon frame, AL S/Arm,Sealed pivot bearings.

[Simon]

One of my first postings was the benefits or not of using a Al s/arm with a carbon frame,I find my 4500 a bit to flexy at the back,anyway I've gone ahead and done it and took the oportunity to carry out some other mods while I was at it,first thanks have to go out to ProflexGB(Nigel) for giving me his spare Al s/arm,Sprucey for getting the axle I designed machined for me,my mate David for the frame lacquer and s/arm paint and lacquer,while I was at it I decided to convert it to pivot on sealed cartridge bearings,after many drawings and re designs I decided on a simple through shaft (axle) running through the frame with the ends machined to accomodate the bearings,I'm using 4 sealed bearings 2 each side measuring O/D 24mm I/D 12mm and 6mm wide,as the s/arm pivot holes are 22mm I used a reamer to take them out to 24mm,I don't foresee this giving a problem with the integrity of the s/arm as there is plenty of material left,one problem I didn't foresee was that the Al s/arm  front inside dimension is narrower where it overlaps the frame so perfect alinement is critical,I also machined down the inside protruding welds to aid clearance issues,this also shouldn't be a problem as the welds look like they had good penetration,I also took the oportunity to machine off the canti bosses,I don't intend to go back to V's and it looks better,also drilled out the frame brake guides to accommodate hydraulic hoses,currenty I'm machining a Al disc adaptor,I believe the Al s/arm with an Al adaptor should weigh about the same as my carbon one with a s/s hammerhead adaptor,infact I don't beleive there is going to be any weight gain,if after I finish building it up and it doesn't break I'll post all the drawings measurements etc for anyone interested,hopefully this will give the desired effect if not ohwell enjoyed doing it anyway plus the outlay was very little,still waiting for some shims so I can fully set up the pivots, heres a link to how it looks a present,
http://idriders.com/cgi-bin/album_k2.pl?photo=simon/Photo0027.jpg or look in my gallery (simon)
Simon.   [smiley=nod.gif]

[Carbon_Angus]

looks good, too!!.....but i prefer the carbon/carbon look....but it does look good and want to see it built up!!

here's a smaller pic i reduced for you, Simon...

did you do this just for the rigidity??? did you notice a diff. with rigidity on your carbon swing when going from a Noleen to a Rissse???

[smiley=beer.gif] [smiley=beer.gif] [smiley=beer.gif]

[bayarearider]

nice paint job.  Did you do that in your garage?  how much prep time did you put into painting it?

[Old Proflexer]

OUTRAGEOUS!!!!

i love it - t3 on steroids!!!!

beautiful work - you are a credit to biking and from all those carbonites out there - thank you.

OP

(didn't home improvement / tool times tim allen have a routine about guys who hang their tools on the wall and outline them so they know where they go when they're done?)

[Simon]

Carbon Angus thanxs for the pic upload,yes did notice an improvment in the lateral movement with the Risse,not alot but noticable,put this down to the larger shaft and eyelet bearings?

bayarearider wish I could take credit for the paint job but that was done by my mate David,he painted it a his work,I did strip off all the origional paint and did the basic prep,took a couple of hours,he took the frame and s/arm, prept them, painted the s/arm ,laquered it with a flexable laquer also added was some gold flex to the laquer,also laquered the frame bought it back the next day.

OP thanks for the comments, intend to do a bearing conversion on a carbon s/arm next if this one is sucessful,disc adapter is coming along nicely,Ti shims and Ti capscrews M8X20 are on there way, intend to build it up over the holidays,will post in files all the engineering drawings and bearing numbers etc if all works out ok,yes used to watch tool time over here in the UK,can't remember the routine though,but Heidi I do remember, drool, [smiley=beer.gif]
Simon.

[Scott]

That looks great!  I esp. like how much the weave jumps out with your topcoating of it, makes a strong case for downsizing of all decals on similar framesets-looking forward to a full ride report

[Simon]

Just thought I'd give a progress up date,so far living upto my expectations,the Al s/arm narrowing mod (described on previous posting) seems to of completly cured the rubbing and is no longer of a concern [smiley=nod.gif],the sealed bearings have been totally reliable and the through shaft seems to be able to take everthing I throw at it [smiley=laughing.gif],I have been regularly stripping it out to check,only takes a couple of mins,easy no quad rings (I did origionally consider making it from s/steel),I also stripped off the frames lacquer as I had cocked up a bit of the prep for my mate,opps [smiley=upset.gif],completly de-decaled now,re-lacquered with a clear coat primer and a topcoat flexable lacquer,been superb since,disc adaptor has given no problems and had no alinement concerns or disc rub,still seem to only get in muddy rides but did get a couple of rides in frosty conditions,definitely noticing the stiffer back end on short steep climbs,and holding a better line on some fast single track thats quite rutty,both wheels now tend to follow in the same line especially off an abverse camber,infact its an improvement alround,still hoping to get others to try it (sprucey,proflexGB), apart from the frosty rides the mud has taken its toll and completly knackered my chain and cassette,so replaced them but they had lasted a long time,think my middle chain ring is also past its sell by date,will replace before next ride,anyway all in all looking forward to my next ride/test,Simon [smiley=nod.gif]