CR 250 primary drive gear collar seal size ?

[spring45]

Hi all, doing my first engine rebuild on my 1987 restoration. Have come to the primary drive collar and the seal inside it thats missing. Clymer says to replace but honda parts drawings dont show the seal. Has anyone come across this and know what size seal to replace it with. Mines an 87 but the collar is the same thru to 2007 on cr250 and 2001 on cr500. Looking on ebay at collars and non have the seal so am i being paranoid or do i face a future prob if left out. Just want to get it right first time round.

Any info much appreciated, cheers.

[evo550]

Have you got a pic of the area your describing ? I can't quite picture a "collar" in the primary drive set up and the only seal I'm thinking of would be a crank seal.
Love the '87's, was a money pit to resto, but looked sweet when done. Can't go past blue seat CR's.

[TMKIWI]

Do you mean the o-ring instead of seal ?
There will be a small groove in the collar that takes an o-ring.
The Honda part lists dont list 1 but my Suzukis do have 1.
Maybe Honda's don't.? Some one can confirm.
You could always measure the groove and pick up an o-ring from your seal supplier.
The o-ring is to stop oil working its way between the the crank and the collar.

[spring45]

Hi Guys thanks for replying so soon, just checked the suzuki drawings and it is the same set up so  i will measure the collar/spacer and go from there. Im going to try attach a pic of the honda set up, the collar that has the o-ring inside is item 2. The collar fits on the crankshaft seated inbetween the crankshaft seal and the primary gear over that.

Been doing my 87 for the past 2 years on and off , it was a stolen recovered so you can imagine the mess it was in. Cant wait to get it running ive heard nothing but good things for this model and im definitely not going to sell it once done.

[TMKIWI]

Yep, thats the one.
The o-ring is quite skinny 0.5mm ish.
Worst case you could probably use a bit of loctite sealant.

[dogger315]

Have come to the primary drive collar and the seal inside it thats missing. Clymer says to replace but honda parts drawings dont show the seal. Has anyone come across this and know what size seal to replace it with.

OK, the reason the Honda fiche doesn't show an Oring is because there isn't one.  There are two such collars on a CR250, one at the primary and one at the shift lever.  Because of the design, only the shift lever collar gets an Oring.
Grease up the lip of the seal and another layer of grease on the collar before install and you're good to go.

dogger 

[spring45]

Thanks dogger your a star!,

now i can carry on with peace of mind. Thanks to the others for there input also, i got no response at all to my post on my home forum in the uk.

Cheers all. spring45

[evo550]

Have come to the primary drive collar and the seal inside it thats missing. Clymer says to replace but honda parts drawings dont show the seal. Has anyone come across this and know what size seal to replace it with.

OK, the reason the Honda fiche doesn't show an Oring is because there isn't one.  There are two such collars on a CR250, one at the primary and one at the shift lever.  Because of the design, only the shift lever collar gets an Oring.
Grease up the lip of the seal and another layer of grease on the collar before install and you're good to go.

dogger

Phew.. I thought dementure had set in early, for the life of me I could not remember an O-ring anywhere near the primary drive seal, and that's why.

[spring45]

Yea sorry about that i think its me whos got the dementure setting in i got confused with it 

[evo550]

Post some pics of your resto, would love to see some.

[spring45]

Sorry the delay in replying, sure i will try get some pics up but struggling with that due to the file size all my pics are 1mb +. Is there an easier way to post photos ? As it is its nowhere near finished but looking good so far, i also have the before pics when it was a proper mess (stolen recovered).

[evo550]

Did you try photobucket?