Crank case assembly question no 2!

[Devondan]

Ok I'm getting nearer the time when the two halves of the yz are going together      So ... firstly what sealant is favourite for the cases that can be bought over the counter? I used to use Hermatite in my yoof,  green I think? 

and I am told that Yamaha always sold cases seperately, ie they werent matched pairs, am I likely to have any difficulty fitting a rightside case off a different bike?  The original may be repairable but the main bearing housing is very lose and the case has a crack, so a swap is easier and cheaper as I have one!

Thanks in advance

Dan

[Denzlepob]

I've missmatched cases, no Probs on Yamaha's, you can use bearing lock on the mains if you are worried, I used blue Hylomar from Ebay http://cgi..._540wt_859

Got any pics?

Denz

[Devondan]

Its not very clear but there is nearly 1mm play on the main bearing housing (both laterally and rotationally) and about a half a mm on the clutch bearing seat, so I'll continue with plan A and swap cases, what sealant do you use between the two cases?  Someone mentioned Honda bond but I cant get that.

Dan

[Evan]

This is what i use. http://www...ealant.htm

[F.Gassit]

1mm sounds alot..................if it were me, I would look at some .5 mm shim stock, cut to size and fitted betweem the case and bearing to take up slack. Use bearing lock to stick the shim paper to the case, not the bearing.

I do the same as this on my wheel hubs when they are out of tolerance...............still going strong.


Three-Bond silastic for sealant is good..............but there are many brands of sealant that will work in this application

[Martin I Henry]

  I take it that the bearing housing itself is moving within the crankcase.
  This is a common problem and one that can be a real pain to sort.
  My IT175E had this happen on one side, and the YZ125E it was really bad on both.
 
  I got Steve Riley ( no relation ) of Piston Broke in Bristol to bore the cases to accept a larger OD bearing that he sourced from somewhere. This did away with the pathetic cast in housings. Personally I prefer the Honda 4T small single main bearing housings, they are cast in like the Yamahas but made from cast iron and you can fit a crank without having to warm the cases or use a puller.

    Don't throw away those worn cases yet, they may come in usesful in the future !!

   The DT175 uses very similar cases to my YZ and IT yet the bearings sit directly into the crankcase without the cast in housings. ' More better ' as the yolkels say at work !!

   Oh, I have also used unmatched cases on a number of brands over the Years.

    Dave R

[F.Gassit]

Oh, I thought he meant the bearings were a loose fit......................my mistake.

[Griffo]

Yamaha use 3bond Liquid gasket Grey. The tube is a maroon ish colour. I can't remember the exact number...

[killindini1]

Yamabond 4,from your local Yamaha dealer.

[Devondan]

This one?   http://www...Three-Bond

Dan