oil on the good foot

[DEEBS11]

I'm not sure one will work on both sides. One has an I.D. of 48mm and the other 45mm. I think that will only fit the 45mm side (right side alternator).

[speedlimit85]

Exactly. That's the problem. The correct replacement seal is available for the right side and Yamaha is listing it for both sides.

Our only choice may be what we have. I am getting 2 of the same seals you are.

Could we ask Yamaha to make a 48 mm replacement seal for the left side?

[DEEBS11]

Here is how the part numbers from one company are laid out. For a 32mm x 48mm x 7.8mm (stock) I figured the part number would be R-B2-1.889-1.259-0.307-(blank space)-SS-V-L for the exact seal. Measuring 48MM = 1.889" and so on....

[DEEBS11]

And a page on installation of seals.

[speedlimit85]

Well, Phil, you were close to right. Instead of a wobble, I have an egg.

I rode into the country to a bike shop today. They let me take it apart and show them the seal. The seal looked good. Then Bullfrog measured the end of the crank and it's an egg shape.

[bikerphil]

So how can that be possible? Is it the sleeve that he measured that is out of round?

[speedlimit85]

The crank end is off slightly. Probably was off the life of the bike but the seal was working anyway- better quality. I just ran into a mechanic friend who has a crazy old school repair idea. Remove the sleave. install a new speedi sleave . Then put the bike on its side somehow with the crank vertical. Put dry ice in there. Soldering gun against the crank, solder into any space and the ice will pull it through to fill all gaps and make it round. Then check with the seal to eyeball if it looks right and if not start over. Then install the seal and ride into the sunset...

[DEEBS11]

Speed, solder, oil and heat & vibration do not mix. That being said, let's take one step back. How was your crankshaft end measured accurately with the seal installed? Did the mechanic use a vernier caliper or a micrometer? The seal would have had to been removed in order to measure the crank end with any accuracy. It needs to be measured right where the seal lip (inner) resides on the end of the crankshaft.

[speedlimit85]

Yea. Bullfrog was nice enough to try and measure with the seal in there and "well there's your problem, glad we solved that."

My mechanic friend's idea may be ok but I will trust your practical engineering.

[speedlimit85]

I got a points file and a scratch awl. I am preparing to remove the sleave.

Another sleave ?...or a different seal with say 7 mm depth so the lip would be sliding on a new groove?

[bikerphil]

Well, providing you can remove the sleeve without any damage to the crank, and can find a seal that would not ride in the groove, I would try it first without the sleeve. If that fails, you could always install another sleeve.

Could you tell if the oil was leaking from underneath the sleeve?

[speedlimit85]

I don't think it was leaking under the sleeve but I tried to look and there is only a bit of crank after the sleeve. There is oil on the bottom half of the seal and crank. through the seal or through the sleeve or both I can't tell.

[DEEBS11]

I agree with Phil that you should try to make the repair without the sleeve unless you see visual damage to the crank end. In the info I posted it required a two lip seal such as the replacement unit we are using have grease in between the two lips of the seal for proper lubrication. This perhaps could be a factor on why we have had early failures with these seals. I think these things are overheating from friction after a few hundred thousand revolutions at full engine heat.

[bikerphil]

I can't remember which, but in my case, I lubed the inner part of the seal with either oil or grease prior to installation.

[speedlimit85]

https://factorysupplyoutlet.com/national-oil-seals-32x48x7-r2ls32-s/

got 2 more on way