Oz main pivot conversion

[Sprucey]

Hi Guys and Girls (are there any?)

just wanted to update you on recent modifications to my Oz.

Last week I asked simon to convert the main swing arm pivot bearing over to his sealed cartridge bearing conversion. I had helped him get the main pivot bars machined by an engineer who works next to me and seen him do his own bike and also Nigel's (ProflexGB?)

The catalyst was my own bushing pivot set was now badly worn and needed replacing anyway - the bike was creaking badly!

Just to report that after my first proper ride I can feel a real difference. The back end is much plusher - so much so that I had to increase the rebound damping on my Noleen Nr2 shock - a sure sign that there is less stiction. Difficult to say if it has made the back end any stiffer torsionally but it has re-vitalised the bike's feel or plushness. Combined with a recent change to a 120mm travel Marz Marathon S coil and swap from carbon flat bars to risers, the bike is super smooth. It is now beautifully balanced front and back.

The real test will be longevity. Those who know me will vouch that I am not small - 220-230pounds! So, if it lasts with me then it will last with anyone. I have gone for a standard Aluminium pivot bar rather than making one from steel - we'll see how it goes.

I felt I had nothing to lose. The Oz needed new bushings anyway, the warranty has expired / been used when the seat post tube insert failed so I thought why not!? I love the bike, the look and the feel and it was the best way to keep it going. The biggest risk is reaming the swing arm out to take the larger cartridge bearings - you lose some metal which may weaken that area - time will tell!

All I need now is a platform damping rear air shock - 5th Element or Manitou Swinger and the bike will be reborn and fit to continue on in the modern world of 21st century long travel free-ride / al mountain enduro bikes!

Take a look at the new Mountain Cycle Fury and tell you don't spot a strong resemblance to the Oz!

Have a good May Day holiday weekend,

Sprucey

[Carbon_Angus]

Simon or Sprucey....With the cartridge bearings.... you still do a "main pivot adjustment" of some type? Adjusting the main is one sure way to get the most out of the frame.

Must be the ale and the mud you guys slosh over there.   I thought the main pivots were pretty long-lived with maintenance.

[smiley=beer.gif]

[Simon]

Simon or Sprucey....With the cartridge bearings.... you still do a "main pivot adjustment" of some type? Adjusting the main is one sure way to get the most out of the frame.

Must be the ale and the mud you guys slosh over there.   I thought the main pivots were pretty long-lived with maintenance.

Hi carbon angus,with the cartridge bearings no adjustments or maintainance should ever be necessary through the life of the bearings(which have still yet to be established),however as this is still a relatively unproven conversion (though its been totally reliable so far) I just like anyone who's had the conversion to strip it out occasionally to see if any issues have occured,
with the origional setup of bushes I used to regularly lube and adjust the main pivot,but as this was a simple job I didn't have any problem with having to do it,
I'd always thought that precision bearings on the Oz main pivot would improve the suspension action,so when I did the Al s/arm conversion I looked into running with sealed bearings,as the designed turned out to be simple I went with it,
the improvement exceded my expectations but as I had put the effort into designing and building this I thought that maybe I was just subconsciouly trying to convince myself that it was worth it,I needed some independent conformation,
Spruceys made my day.

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

Simon  

[Old Proflexer]

necessity is the mother of invention -

happy riding sprucey, for plush, consider a coil over such as the 5th over an air shock.  i lose a lot with my fox on the back end when pumped up to what i would consider spec's so i run it a little low - to cover sag, too stiff and harsh for me -

too bad you guys weren't around when the 4500's were on the drawing boards and at the testing circuit.  also, too bad that shock technology was about 5-7 years behind the hard to improve upon, mono pivot design.

i hope you enjoy your 'new' bike sprucey and i sincerely hope simon will make millions by selling his design back to k2 for future production.

OP

[Simon]

i hope you enjoy your 'new' bike sprucey and i sincerely hope simon will make millions by selling his design back to k2 for future production.

OP

I wish,the design is just a freebee for anyone who wished to do it,mind, if they ever reproduced the Oz (we can only dream) I would hope the pivot design run on some form of precision bearings,

Simon.

[Carbon_Angus]

Thanks, now I want one, too............

[smiley=beer.gif]

[Thunderchild]

Do you have any pictures of the conversion process, final product, etc.  

[Simon]

Do you have any pictures of the conversion process, final product, etc.  

Hi Thunderchild,check out my gallery (Simon) and the files section,all info Pic's and relevent drawings are there.
Simon.