Kirk Revolution I refurbed last year (my first retro refurb)

[Rebikecumbria]

Hi Retrobikers, I thought I would share this one with you all

I ve tinkered/destroyed/fixed bikes since I was a nipper and other than a brief stint working in a bike shop in Brighton at uni and later in my 20s being a shop racer I’ve never been a proper bike tech or been let loose in a bike workshop till last year

Also I ll admit I ve never really had much to do with classic or retro bikes other than thinking back to my first proper mtb as a young teenager (97/9 since then it’s been what’s new, fast and will send something big

Anyway last year before I had even heard of retrobike and had only been at Rebike for maybe 4/5 months the manager let me loose on an old Kirk that came in

I wish I had some better pics but my phone went for a swim end of last year and these are the only pics I have recovered off my Icloud

Tried my best with what parts were about to try and keep it period correct but being a little bit of a newbie I am sure there’s some that aren’t the done thing (please let me know I am def interested in some constructive criticism ; ) )

It got a lot of interest on the shop floor once I finished it

my other colleagues took full p!ss on my colour scheme ahaha but I thought matching the neons and colours were very late 80s early 90s ski suit vibes

I ve never ridden something so flexy though it was quite something to experience, I was worried it might snap and it would turn an arc by flexing the front end without turning the bars at all

It has since sold and if I had an account then I would have surely posted it

anyway my first proper retro build/refurb, it was a lot of fun and a good learning curve researching these strange mag bikes : )

 

[MuchAlohaNui]

I think the Kirk bikes are super underrated, in my opinion of course. The old advertisememts were very querky with the owner running over frames in a parking lot with a truck. Your bike is pretty sweet and the components on yours is the direction Kirk failed to take. These frames came factory with Shimano LX for f-kirk sake. Still want one though! Thanks for sharing!

 

[STX-RC]

I saw one recently and it was very heavy and seemed rigid. Is it possible that it was not magnesium, but maybe alu?

 

[Rebikecumbria]

I think the Kirk bikes are super underrated, in my opinion of course. The old advertisememts were very querky with the owner running over frames in a parking lot with a truck. Your bike is pretty sweet and the components on yours is the direction Kirk failed to take. These frames came factory with Shimano LX for f-kirk sake. Still want one though! Thanks for sharing!

Thanks dude it was a lot of fun working on it and researching them, there’s a stunning pic of one on Pinterest I think with Rubaix forks and colagno wheels that looks epic

a knowledgeable old engineer bloke who comes into the shop now and again had lots to say and inform me about them too

supposedly they didn’t flex as much as they do now as supposedly the mag alloy degrades in strength over time was what he said (wether that’s true or not I don’t know)

unfortunately I wasn’t in the day it sold so I never got to meet the new owner

maybe one day I ll see it again hopefully it ll be well looked after and not stripped for parts ahaha

 

[Rebikecumbria]

I saw one recently and it was very heavy and seemed rigid. Is it possible that it was not magnesium, but maybe alu?
View attachment 695135

they are quite heavy these days but were considered quite lite for the day, def not alu they are all hydraulic pressed magnesium (similar to how mag alloy wheels are made) under huge forces - they aren’t one piece though a few pieces that are glued together

the one I was working on I fully inspected and the glued areas seemed ok

it was bloody flexy though that’s why I put the flex stem on as kind of a joke to add more flex ahaha but it worked quite nicely with the cro mo rigid fork (original)

 

[Mod-Master]

I like the Kirk but think it looks soooo much better in road bike form.







Flexy bike = flexy stem

Heheh

 

[MuchAlohaNui]

Wait a sec...where the heck are the joints glued? With flex..maybe just go all the way and back out all your spoke nipples four or five turns . No no...don't do that I don't want you to die...unless you are leaving me the bike in your will, then in that case do what you like.

 

[Rebikecumbria]

Wait a sec...where the heck are the joints glued? With flex..maybe just go all the way and back out all your spoke nipples four or five turns . No no...don't do that I don't want you to die...unless you are leaving me the bike in your will, then in that case do what you like.

The frame is a few pieces and if you look around the rear triangle and seat post area that’s where the glued bits are, also the rear brake bosses are glued in as well with some pinning screws

the ringle wheels were spot on no flex there ahaha

 

[focomat 1c]

Re:

Kirk problems are mostly related to a failure of one or more of the resin bonded joints

There are tubular inserts bonded in to the headset area , and also the bottom bracket

The rear dropouts have inserts bonded/screwed in to avoid fretting of the alloy by the axle

The various cable guides are all bonded in

Both the seat 'tube' and down 'tube' have panels bonded in to their rear and lower surfaces respectively ,
in my view this is the area of the bike that has produced the most problems . If the bonded joint at the edge of
either or both of these panels fails , the torsional strength of the 'tubes' will be considerably reduced .
The fault will not be visible without minute examination , and the bike will not ride well !

Any loose inserts are best removed , and the old resin removed with a hot air gun , before re-bonding the
components . The top tube cable guides can be re-constructed with resin if damaged .

The hard to find component is the gear hanger , which is a design unique to the Kirk

I have not heard of a frame cracking as such

The lack of sufficient quality control was a major contributor to the poor reputation these bikes had and still have

If you wish to restore one , I would recommend that you first use a penetrant dye crack detection system to confirm the
integrity of the bonded panels

Re. the frame material , I seem to remember that due to problems with using magnesium in the pressure die casting system
the very first bikes shown at a bike show in the US were in fact aluminium

 

[Rebikecumbria]

The lack of sufficient quality control was a major contributor to the poor reputation these bikes had and still have

If you wish to restore one , I would recommend that you first use a penetrant dye crack detection system to confirm the
integrity of the bonded panels

Re. the frame material , I seem to remember that due to problems with using magnesium in the pressure die casting system
the very first bikes shown at a bike show in the US were in fact aluminium

That level of CSI type deep dive resto’ is definitely above my pay grade!

but some excellent information thanks, I didn’t know about the internal bonds around the head tube and bb - I couldn’t see and marks but the paint job was pretty impressive