EC250 '98 gearbox questions

[Leon_gasgas]

Hi all!

After checking for damages in the gearbox of my bike ('98 year model) I would like to ensure that I put back in the correct order all the parts. The manual is clear enough for the order of the sprockets and the shift forks but not so clear for the mechanism which shifts the forks. Can somebody instruct me for its correct position in relevance with the forks?

Now I have put it in (I haven't assembled the cases yet) with the 2 left forks placed in the "lowest" (deeper?) "path" and in the "highest" path respectively on this mechanism. The one right fork is placed naturally in the middle path of this mechanism. Is this the correct order? By hand it shifts the gearbox into two obvious positions. The one in which everything turns around and the one in which (as I remember) 1 or 2 sprockets don't turn around. Into how many positions the gearbox should be shifted by turning the drum by hand?

Here is a picture of the forks in relevance to the primary axis and the drum. It is natural to me that it should be like that because the primary axis can receive one fork only. Can somebody verify?

http://img142.imagevenue.com/img.php...lit1_448lo.JPG

I hope my description is clear enough for you to understand! Waiting for your replies!

Thank you!

Leon

[Cruiser]

Leon,
It looks good in the pic, but its been a long time since I had my 97 apart. Hopefully GMP will post as he probable has pics of his trans apart.
Good luck,
Steve C

[GMP]

Sorry, last time I had one apart I had no digital camera handy.

It looks OK, but assemble it into the case and shift it through the gears. You can even temporarily assemble the case halves without the crank or gasket just to check this.

One thing to be carefull of is its possible to install first gear both ways on the countershaft, but only one is correct. It looks symetrical at a glance but there is a very slight offset. If its on backwards the trans will bind when the cases are mated.

[Leon_gasgas]

Thank you for the replies!

This thing about the first gear confused me a bit. How do I check it? I tried once to shift gears by hand with the gearbox assembled and the shift drum into its needle bearing but it stopped shifting (I don't remember to which direction I was shifting) after 1 or 2 shifts. It felt like the "deeper" left fork (left in the pic) got stuck and couldn't move. I will try it again now to see how it goes this time. Should the drum turn clockwise to shift gears upwards?

Thank you again for your help!

Leon

[Leon_gasgas]

Hi again!

Ok, I thing I understood what you wrote about the 1st gear. There was a picture in the manual too, showing which side of the gear should face the case. Tonight I will try to put everything together. The double rubber o-ring which is near by the outer front sprocket is damaged. It's like one side is ok and the other is less than half. Can I take this small part off and use a new single o-ring together with the old one, or is better to order the OEM one?

Best Regards,

Leon

[GMP]

Get two new OEM o-rings, new collar, and a new seal. Inspect the collar and you will most likely see a wear groove. Also, clean and inspect all the bearings. Personally, if I'm going through the trouble of splitting cases I change everything, all seals and bearings, and upgrade to higher grade parts where possible.

[Leon_gasgas]

Ok, I'll do that. It felt that the two outer bearings of the gearbox opposite from the chain sprocket were stucking so I replaced them with OEM SKFs. The other bearings are OK but maybe I will replace them because I have their replacement SKFs.

The funniest thing of all is that when I opened the cases to fix the hole on one, I found a broken big tooth but everything seems fine! All the gears are ok! Where this tooth came from? Any clues?

Best Regards,

Leon

[Leon_gasgas]

Thank you all for your help! The position of the shift forks was correct. Yesterday I started the bike and everything worked ok. I have put a new Vertex piston (the old one was still ok after 120 hrs asking only for new springs) as well, so tomorrow I will break it in well.

Thank you!

Leon

[Leon_gasgas]

Hi again,

During yesterday's break in it was quite impossible to shift from 2nd to 3rd. It was shifting to neutral and after a second trial it was shifting to 4th. It felt great shifting to all the rest of the gears. I always used the clutch. Because I was driving up and down a normal ground road I was wearing my normal hicking boots and not the enduro boots. Can this cause this problem? It was hard to downshift too between these two gears.

On Saturday when I drove around my home to check if things are ok, it was hard to shift from 1st to 2nd. Then I was using even softer shoes. Tomorrow I go for practice so I will wear all the enduro equipment. Should I check something else? With the bike turned off I can put it to 3rd easily by hand! I am really frustrated because except this problem the bike feels like new.

Should I change the position of the shifter? Something else?

Please help me! I wouldn't like to open the cases again.

Regards,

Leon

[GMP]

If everything worked correctly on the bench (shifted OK) you should have no major problems related to assembly. First thing is to check if your clutch is dragging. Was it bled properly? Let us know. Also, what if any parts were replaced in the transmission? There have been some updates since '98.