i've had these old konis that came with the bike when i bought it. they're a nice period correct upgrade but honestly, after 40+ years they could do with a re-fresh.
there's just nothing like those original koni alu bodies so i definitely wanted to keep them, while giving them as much of a performance boost as possible. geoff from ikon in australia was of immense help in figuring out what to do.
i sent him the specs and measurements of my ikons, while he dove into his archive of documentation and parts to figure out what we could do.
we agreed to fit internals of the current ikon series and add a progressive spring. as easy as that sounds, it took a lot of research, mix-n-match of components, and some custom fabrication to get a set that would fit the old bodies.
from the first time of contacting geoff until i received the package with the parts, took 3 years.
while this sounds like a long time i'm aware that most other commercial businesses would not even bother with such a request at all. i'm super grateful that they had the commitment and patience to work this out with me.
anyway, after the package arrived i could get to work.
here are two articles that i found helpful with the nitty-gritty stuff:
http://forums.sohc4.net/index.php/topic,173257.0.htmlhttp://www.zimmerframeracing.com/koni_shocks/index.htmhere are the stripped-down bodies.
on the left are the lower spring seats. they had to be replaced because the new progressive spring has a larger outer diameter than the old one.
i had to ream out the new seats to fit over the bodies. apparently, the current steel bodies are slimmer than the old obese alu ones.
disassembling the shocks is messy business. there's a mix of antique oil and dissolved pastic stuff in there that smells absolutely disgusting.
here the old and new internals for comparison.
the new pressure tube will need to be cut down so that the complete new assembly will have the same hight as the old one. some careful measurements needed to be taken here.
while one shock came apart relatively easily with just a bit of persuasive force, the other one just didn't want to budge no matter what we did. heat... tapping... cursing... nothing helped.
what did it in the end:
make a little cup around the top out of pastic foil, fill it with a 50/50 mix of acetone and ATF and let it soak for a day.
then put the thing in a vice and hold the spanner down with a piece of tubing. some extra leverage and lean into it...
... and there we go - that awful smell again! the smell of victory, i suppose.
here now the completely rebuilt and refreshed shocks.
looks like this now on the bike.
they work really great. contact to the road is noticeably better, and cornering is more confident. this took an awful lot of time to realise, it's probably a but of a nut job but i'm happy with the outcome.
