TR1 1981 fork cap  problems
I started to upgrade  the forks with new seals and progressive springs when I noticed one of the fork caps which (is held in place by  the cir clip) had been forced down past the actual groove (where the cir clip mounts) so i removed the cir clip
and gave the fork cap a couple taps with rubber hammer to see if would break free
but it refused to move
I have since left it soaked in  penetrating oil put seems to be seized  tight in the fork tube
any advice would be great

HELPPPP

Halo tophased,
I hope I understand your problem correctly.
Just try to warm up with the fork with a hot air gun. When everything is hot, maybe you can push down the cap with a clamp.

Good luck, Karsten

I would ty to push the fork together and give a few beats on its top with a metal hammer. Keep the face away! Or screw out the air-valve, turn a screw into the plug and try to pull it out with that screw.

Bye,
Georg

Hallo tophased, hallo Georg

I wouldn´t beat on the top of the cap with a metal hammer, because it´s very easy to damage the chamfer, where the Oring sits.
Georg´s second proposal is much better, but you need a srew with, if I remember correctly, M7x1 thread.

Best regards, Karsten

Gredner wrote:

I wouldn´t beat on the top of the cap with a metal hammer

I didnt mean to beat on the plug, i think someone has already done that. Thats why the plug is stuck inside the tube. Try to beat on the tube.

Bye,
Georg

Hi,

that's quite normal.
First loosen the upper srew of the fork bridge, just a bit, to make sure that there is no pressure around the tube.
Then use a tube or someting round and hollow that is smaller in diameter than the fork's tube. Put this on the cap and use it as a chisel.
You may use a real hammer for this, because there is nothing You can damage inside. As soon as the cap gets loose, You will feel the spring going down. May be You will have to press the cap down and let it come up again a couple of times, until the cap pops finally out of the tube.
When You have let the air pressure out of the fork (!), and there are the original, weak, flat springs inside it, You don't have to fear much. The cap won't pop out for more than two inches.

Cheers,

Stefan

The cap should break free this way. Anyway make sure that You use a good lubrificant.
There is absolutely nothing inside that can block the cap seriously in this position. That's why I suggest to hammer it further down. The spring will do the rest.
It seems that someone tried but did not manage to get the cap out before. After 30 years there is so much dirt between the cap and the tube. Worst are the bikes that have been standing out in the cold and the rain.

Just hang on,

Stefan

thanks guys
ended up spraying half can of Loctite freeze and release lubricant on to the cap
while using a bike (air) hand pump and to crease the pressure in the fork ( i had to change the seals too)
a couple of little taps on the cap with a socket and hammer . that worked
the cap shot across the garage  like a rocket taking out a set of works lights !
except now the air valve on the cap is trashed !!
oh well at least it came out !!

You could have killed yourself with that air gun. It's no good idea to pump the fork up like that. The force of the spring is more than sufficient.

Stefan

hi Stefan thanks for your concern
but don't worry
I used a bicycle  hand pump not an air compressor !!

Hello all and sorry for the resurrection again.

I have a question before I engage on this job.

How is the cap/circlip removed. I never had a bike with such fork.

I know the asnwer must be in the service manual, I asking if there are any tricks for this.

Evros

Hello Evripidis,
I guess you want to remove the Cap to take out the springs inside of the fork-tube?

If it is so, remove the Steering bar to get enough space. Be careful , so that no Brake fluid escapes from the reservoir and perhaps damage other parts, e.g. your Fuel-Tank.

To remove the Caps it self you will need
 - a small Screwdriver with blade end, /(for slotted screws),
 - a Wrench Nut which fits to the Air Valve hex, and a suitable tool to get more distance for better workspace.
1. Take the wrench Nut assembly onto the hexagon socket of the air Valve
2. Puch down the Cap, enough so that the circlip inside is fully visible.
3. with the Screwdriver you can level out the beginning of the circlip. But be aware that the circlip is not jumping away. It it difficult to find it.
   It is a little bit tricky, but it will coming out.
4. Now let the plug (Cap) coming out by releasing pressure. If the Plug is not coming out at the first time, try again to push the plug into the Fork Tube and than release the pressure of holding down immediately. If necessary try it several times.
Reason could be some dirt inside, or a little bit of deformation of the grove of the circlip.

Regards Anja

Hallo Anja,

Thank you this makes sense now.

In reality I only want to replace the fork seals. The entire fork does not have to be taken apart, but I am afraid that I might damage the surface by trying to prise out the seal. I have done it before but I am afraid to do it on this bike.

Evros

Hello Evripidis,
one  at first. My Description belongs to the removing of the Fork-Tube-Caps (Imags No: 15/38) with the Air valve in it.

Do you want to change the Oil seals of the Fork?
If you want to go ahead with your scheduled Replacement, be aware not to scratch the inner Tube !!!

Primary, it would be better to take the Front Fork Units out and fix them on your bench.

I have attached to images with parts of the Fork Assembly:
8 /31 = Dust Cover
4/27 = Circlip of the Oil-Seal
3/26 = Oil-Seal

Regards Anja

Hallo Anja,

Thank you, I read the parts catalogue and will also go through the service manual dilligently.

I will replace the oil too and renew the seals. Already ordered the seals becuase my usual supplier does not have them in stock.

I can handle this but I have another question.

Can I remove the front shocks when the bike is on the centre stand? Or do I need support?

Evros

Hello  Evripidis,
you need to support the Engine !
-----
have a Look here:
https://www.tr1.de/pages/forum.php?iQuery=num=1724322130/3&anchor=3

Re: Zylinderköpfe demontieren an der Yamaha xv1000 tr1 5a8
Antworten #3 - 26.08.24 um 10:42:34
including a drawing for a selfmade Enginesupport (german: Motorstütze)
see also the pictures one abow
-----
You can use it for:
when using two additional clamping wedges to lift it a little bit (until the the Front Tire has cleard the ground):
- for Front Tire change
- for Works on Front Fork

without wedges:
a) loose Front Fork Clamps a allow Fork Tube to slip up, the Engine support device has to be come to the Ground.
Then:
- for Works on the Engine. e.G. for removing Cylinderhead / Cylinders

IF you are support your Engine by using a Wood Block or a hydraulic lifter, be aware to secure this safely to prevent falling away your Support from the Engine.

While working on the Front Fork, taking out a Tube or so, it is possible that your bike can come to a swinging. This swinging can shake your support away, if it is not fixed in position.

regards Anja

Is you ask or write hard enough in the forum, you can possibly make the bike stand upright by itself, see also https://en.wikipedia.org/wiki/Snake_charming

Otherwise just put a jack under the engine...

Sorry, but i really can not resist...

Hallo Anja,

I did it differently! But your plans are spot on and will at some point implement them.

I drilled 2 holes in the ground and attached a hook. The I used a ratchet strap to tie down the rear end very lightly. I had enough clearance to remove the forks.

Now I am back to read again what you have written about removing the cap....

I might have a hard time.

I think that the forks where filled with the wrong oil, it was too thick coming out....

Evros

OK, here you go. Pictures of the support for removing the front forks.

And then a contraption I devised to get the circlips out. After a lot of huffing, puffing and penetrating liquid  ;)

I decided a tool is needed. So I used what I had in the parts bin. It is pretty self explanatory.

Got it out pretty easily then. Bit crusty but will be fine. I should have replaced the springs but I'll do a rebuild at some other time. Teflon rings and tubes.

I will try and get wirth or hagon.

Good Moning Evripidis,
your TR1 looks good, so far.
You are very creative, indeed.

Fork-Oil : 10W , Volume per Tube: 288ccm
Kind regards
Anja

Hallo Anja,

Thank you for your info. I saw in the manual 274ml so that is how much I put in. I did not know about 288ml I don't suppose it will make much difference.

The old oil had gone very,very bad.

Evros

Have a look:
https://www.tr1.de/pages/technics_manual.php?key=XV750se&lng=eng&flg=0&pge=2032
Regards Anja

Hallo Anja,

Thank you. This is confusing. Have a look and see what I mean:

1. https://www.tr1.de/technics/service/XV750SE_SM_5G5.pdf

Page 347 of the pdf - 278ml

2. https://www.tr1.de/technics/service/XV1000_TR1_SM_5A8.pdf

Page 59 of the pdf - 264ml

Evros

XV750 and TR1 have different forks. The first is a 36mm diameter and the latter a 37mm fork. Also, if you're able to feel the difference of 14ml fluid, you should probably NOT ride a TR1, but apply for a motorcycle road racing series. ;-)

Also depending on your weight and whether you plan to use the air-assist or not, you may want to add even more oil as well.

(I've run XS1100 forks in my TR1 for close to a decade now, so I am not sure how much oil I used to use in my TR1 forks, but I think somewhere in the ballpark of 15 percent extra oil.)

Cheers,
Greg

Makes sense then. I never thought to check the seal diameters from the catalogue.

In any case, I don't think it is that critical for that quantity. It should be all right.

My weight is exactly 1/3 of the tr1!

Not entirely sure, which number you're referring to, but regardless of which, I think you're due for an extra Baklava after lunch just to make sure you don't get blown off the bike.  ;)

I meant to check what the oil seal size difference is between the two bikes, as you say the have different tubes. I did not know which oil quantity was correct but after thinking about what had come out the tubes, I decided that whatever I put in would be an improvement!

It is impossible for me to gain weight. I have tried.

Minimum 290 ccm per fork leg. https://www.tr1.de/cgi-bin/yabb2/YaBB.pl?num=1628266373