1991 FZR 1000 RU fork problem SORTED

[watto1]

Hi Guys hoping somone here can help I`m trying to sort out my bike and have bought new stantions for forks but cannot get the old ones off the bottom of the forks any ideas took them to lo0cal engineering company and they have no idea getting desperate now only done 12 miles in 8 months
thanks in advance Don.

[DonTZ125]

If your local mechanic can't strip USD forks, it's time to find another mechanic.

We had this discussion over at the Archives recently - http://www.fzrarchives.com/ipb/index.ph ... ntry447834

Once the cap is completely off and the spring out, the upper and lower should simply and easily pull apart.

[yamaha_george]

If your local mechanic can't strip USD forks, it's time to find another mechanic.

We had this discussion over at the Archives recently - http://www.fzrarchives.com/ipb/index.ph ... ntry447834

Once the cap is completely off and the spring out, the upper and lower should simply and easily pull apart.

Hi,
whilst not for FZR1000 per se this is for SHOWA USD forks in general












It should give you some idea what you are up against.

Don as for the tools, that fork shaped tool to hold the spring in place I used a big sod off penny washer and took a hacksaw to it to make the slot ( so just pass this old monkey a banana LoL)

[watto1]

Hi thanks for your help but I don`t think I expained it very well the forks are striped down ready to fit new stantions/tubes but I cannot for life of me work out how to do it I know the bottom screws in but there seems to be a grub screw on the inside that will not move and one has a broken bit inside I`m thinking lots of heat and try unsrewing tube from the nuckle that holds wheel, mudguard and brake caliper .

Thanks Don.

[yamaha_george]

Hi thanks for your help but I don`t think I expained it very well the forks are striped down ready to fit new stantions/tubes but I cannot for life of me work out how to do it I know the bottom screws in but there seems to be a grub screw on the inside that will not move and one has a broken bit inside I`m thinking lots of heat and try unsrewing tube from the nuckle that holds wheel, mudguard and brake caliper .

Thanks Don.

Don,
ahh I see the light now, yes there is normally a grub screw holding the inner stantion tube to the casting that holds the calipers & spindle. (otherwise the tube could vibrate out and cause catastrophic failure.

Having looked at the Showa forks there is a grub screw in place and from close examination it appears to have locktite on it..

It will require by the sound of your problem that the broken grub screws be drilled out now this is NOT ajob you can do with a pistol grip hand held drill.
I would take it to a machine shop so the stantions can be locked in place so that the screws are as perfect to vertical as possible and using a Cobalt drill (grub screws tend to be case hardened steel ) slowly drilled out.
In the event that this goes wrong they are in a position to drill the hole out over sized and re-tapped for a bigger grub screw.

I know that getting a machine shop/engineer to work on this is an expense but IF you want it done right and worry free it is the way to go.(i.e the way I would do it personally in your position )

[watto1]

Hi thanks for help managed to do 1 fork tube with lots of heat but the other grub screw has a broken torx bit in it from a previous atempt I think !
so will keep you upto date on how it goes

thanks again
Don.

[yamaha_george]

Hi thanks for help managed to do 1 fork tube with lots of heat but the other grub screw has a broken torx bit in it from a previous atempt I think !
so will keep you upto date on how it goes

thanks again
Don.

Don,
that broken piece MUST be removed as it is hardened and made even harder by the action of breaking. This I suggest you make an engineer in a machine shop's problem as they have the right equipment to deal with busted drill bits etc.

I have done this kind of thing but having a fully equipped shop behind me to use as I saw fit, I, even with my background & experience would not try "something" at home it would go wrong far too easily with expensive results.


Having got the advice bit out the way, let me ask you where you put the heat when you took the other one apart ?
i.e. on the stantion leg or on the casting ..............

and

what was the source of heat ?

[watto1]

Hi heat casting by grub screw to soften thead lock but use gentle heat used gas blowlamp only to soften thread lock but not on stantion.
I took them to a precision engineer at first after 3 days he gave them back saying he could not do them so to be honest I`d rather strugle on my self or buy a bent fork leg and start again

Don

[yamaha_george]

Hi heat casting by grub screw to soften thead lock but use gentle heat used gas blowlamp only to soften thread lock but not on stantion.
I took them to a precision engineer at first after 3 days he gave them back saying he could not do them so to be honest I`d rather struggle on my self or buy a bent fork leg and start again

Don

Don,
Oh dear sorry to hear that, I would assume that he has no knowledge of bikes & their forks and was not prepared to "go brave". All I can say is do not be in any rush whilst working on this 2nd leg.


Q:- is the torks bit sticking out the grub screw or is it sheared flush with it ?

[Ice Queen]

Might be an idea to find a Cylinder head shop type place that have a spark eroder. That'll get it out without touching the original threads

[watto1]

Hi its broken about 1mm from top but no worries just bought a second hand leg from another forum should be here in few days then the fun will begin again the shop i took them to is a biker but oh well won`t be bothering him again thanks for your interest Don

[yamaha_george]

Hi its broken about 1mm from top but no worries just bought a second hand leg from another forum should be here in few days then the fun will begin again the shop i took them to is a biker but oh well won`t be bothering him again thanks for your interest Don

Don,
Let us know how you get on.
Y_Geo.

[yamaha_george]

Might be an idea to find a Cylinder head shop type place that have a spark eroder. That'll get it out without touching the original threads

IQ,
that would do it, but I only know of 2 between here and Oxford they are kinda rare animals. I did get some work thro the back door of the one in Kingston but the other one was 70 an hour and they were NOT friendly at all.
So much so I sent my last work of that kind to Canada it worked out to be 35% of the UK cost and that included postage each way.

[watto1]

Hi biught second forkleg off other site spent half hr with wd40 and blowlamp and I`m now all sorted
thanks for all your help and comments ( Bikers do it better )

Don.

[yamaha_george]

Ahh another satisfied customer