Topic: old koni shocks

[Cyclone82]

Yes the shaft guide bush is the big round stepped bit that the shaft goes through and the o-ring sits on
Normally in any other shock rebuild this bush is either in a one piece seal head and you replace the whole unit or you can easily replace the bush by drifting it out of the seal head or holder with a special tool. It looks like im getting 11.80 when i measure it. It feels looser than it maybe is. I have had some Fox shafts chromed and had new bronze bushes made to suit the shafts and they just have a bit of grab on the shafts and are not real loose. I have the same guy inmind to re-bush these Konis. I spent more time looking at that last night and it definitely looks do-able now. We would bore out the bush to a larger diameter, make a bronze stepped bush, press that in, then drill through all the little holes so its back to how it was before, then do the final finish boring of the bush to 11.75mm/suit the shaft. Then de-bur the holes etc. Im quite confident it will work. I need to ask my machinist/shock guy things like whats the minimum wall thickness he can make the bronze bush wall etc.

Yes tonight i have just realized the shock piston wall is thin, may not be thick enough for a wear band?? I could not get my piston off the shaft tonight so will attempt that tomorrow to get a closer look at what can be done in that area. One of my sets has a thin cast iron piston ring about 1.5mm wide. I may even be able to replace this a ring machined from that white teflon/nylon material some shocks use for piston rings. My later model Koni gas shocks use 5mm wide piston rings in that material.

I have got a decent rebuild guide comming on these Konis. Should have it this next week. I will then scan and put it on here. I also have a list of all the Koni part numbers for each bike at the time of 1975. Need to scan that too, hopefully on the weekend.

External bump stops shoudl not be a problem either. Ikon says the 7610 internal top out rubbers work in the 76F series too.

One of my shafts is bent so i will probably just get new ones made. I have  another source who can make these for approx $60 US each i reckon, just depends on how many he can make. If there is interest he can make a batch no worries, infact he prefers to make batches of shock parts.

I maybe able to get some NOS pistons too. I will have more info on that next week.

[Markcb750]

One of my shafts was bent also, must be a common result to a jammed piston. I could not find replacement parts at IKon or any Koni shock specialist I found via Google, so if you can find one it would be great for keeping these classic performance parts running. 

One of the members here had a damaged Koni  body that I acquired.  I extracted the piston, which is an intricate little part, and the shaft.  His shaft was 0.302" shorter then mine.  so I made a series of spacers to make both shocks stroke 0.302 shorter, reducing the eye tot eye length on both shocks to about 12 7/8 from the original 13 1/4. 

I think you can straighten a shaft if you have a set of machinist V blocks and a hydraulic press.  I attempted straightening  mine in a soft jaw vice.  A slip under pressure broke the piston thread finishing the old shaft off    and leading me to the solution above.

Mark

[Markcb750]

Is this the seal you are looking for?

[Cyclone82]

Wow! yes it is. Have you had some made? Any chance you could email me the full size copy of that? Not sure i would get any made but it would be good to add to my koni info folder which i will post a lot of the stuff on here. I think i may have found a cutaway drawing of these shocks.

If someone makes these seals they will sell out fast. A guy told me he had some Corte & Cosso seals made and said they sold out real fast on ebay.

Have not decided what to do with shafts. That is the easy part though

[Markcb750]

I know some seal manufactures, I made the print and was going to see how much to have some made.  You should be able to print the Jpeg and it will be full scale.

I have not guessed at the tolerances. I want to get some feed back from manufactures first.

[Cyclone82]

I have inquired about getting other rubber parts made before. I need to get some square rings made for some other shocks. I will find the place i contacted. I would  certainly buy a few dozen or so of these Koni seals if we get them made.

this is the place i contacted http://www.alliedseals.com/ but im not sure they do these sorts of shock seals

this would be the place to try http://www.epm.com/ i now remember contacting these guys too.

I saved that drawing but even at full size its blury/distorted.

[octagon]

the piston unscrews regular right hand thread from the shaft as you guys probably already know. i wrapped mine in fine emory paper and used small channel lock pliers to remove. but if you must grab the piston at its base not at the skirt end or it will break.
super drawing of the seal.

[Cyclone82]

Ok i have got the little 11mm/7/16 hex bolt out and removed the 2 pronged part, a spring and a thin hex shaped disc. Now you tell me the actual piston is threaded on too??? If that is right thangs for telling me before i go and try an knock it off anymore. Most other shocks have the piston non threaded and it just slides onto the shaft.

It will be hard to unscrew mine as i have the piston ring in that area. I hope they did not use Loctite! i will proceed with caution with this one but i really need to get my pistons off because there is stuff jamming the shims.

[octagon]

my pistons are plain so there may be other differences between them and yours. but on mine that bushing with the holes drilled in it seems to be pressed up into the piston, and the bushing has threads. so if you grip the piston carefully, not at the skirt end, but at the top end where the bushing is you can unscrew the piston-bushing assembly. i haven't tried to separate the two but believe me that piston is easy to break so go slowly with it.

[Cyclone82]

Sounds like we are talking about different things here???. We need to get more photos in this thread to save confusion!

Well today i carefully removed my piston ring, that was not too hard. I clamped the shaft using 12mm Ohlins shaft blocks and wrapped some wet 'n' dry paper around the piston. I tryed to grab and undo the piston but it was tight an too risky. I had already put a couple tiny marks in the piston from the channel lock plier jaws. No a real good thing to use. I was able to sand/polish the couple marks out Ok. I will not be attempting to undo these till i geta proper clamp block made I need to get a 21mm clamp made to safely grip the piston.




Im this photo i have not shown the little hex bolt i first took off or the metal piston ring.
It looks like i would be able to get the piston ring groove widened to take a wear band. I know various suppliers i can get it from. I should be able to go to 3.9mm wide which is a common width in White Power shocks and i have also found a US site that has this width band in 1mm thick. You could even buy some wide band and then get a knife and slice off a strip. So no big issues here i dont think. Sould be able to fit a nice modern band for smooth operation and then replace them often and never have to worry about metal to metal contact in the inner tube wearing it out.


Just a shot of the inside of the piston. So yours was threaded on the shaft. Dont know if mine is but i guess it would be if your is.

[strangedaze39]

Has there been any updates on the outcome of locating seals? I have a set of 76F shocks that use the same seal you guys are talking about, and need a couple.

[crazypj]

I know I contacted IKON in 2011, they didn't have anything to help, but, would sell me new shocks

[Opposedsix]

Bump for vintage KONI question(s) 

I recently acquired a nice set of 76F - 1302 and was contemplating an IKON Australia rebuild verses my options...

Has any member sent their set to "koniking" on fleabay for a rebuild? Your thoughts on his workmanship?

Where have you sent your set to be rebuilt?  Whats the fee from IKON?

Huge thanks in advance.

[rhaagusa]

Just want to let you all know I have any early KONI parts and service available. Robert Haag/ Konimon  rahaagusa@ yahoo.com

[flybox1]

Just want to let you all know I have any early KONI parts and service available. Robert Haag/ Konimon  rahaagusa@ yahoo.com

post this over in the services offered section, with pictures and details. we like pictures 
you'll get better responses over there.

[Duke McDukiedook]

Sweet, good to know in case I score an old pair on the cheap.