Switching Premix oils

[TZ925]

Since there is a topic open on the A747, which I agree is the best treatment you can give your GP baby, who has heard the myth about not switching from the premix you broke your crank in with? I currently use Silk Pro2 and have had no probs but would like to switch to 747. I've heard people warn about changing untill you do a new crank. Can anyone substantiate this or is it BS? FYI, people haven't seemed to notice that the 747 is roughly $20 per LITER, while the Silk/Motul good stuff is around the $8 1/2 liter mark. Not counting dealer discounts and such the 747 should only be $4 per liter more and it sounds like it's worth it.

Monty Warsing
PS-The new TZ rocks!

[Bill Cole]

Monty, First of all great news on your new TZ. It will be a winner for sure in your hands. Congrats!!!

On the oil swap... When I was ready to switch Kevin Murray was very clear that this can only be done after a rebuild. I remember that he made some comments that the oil will be absorbed into the metal. When you change the 747 will sit on top like a film and not protect as it should. He was very spacific on this.

Bill Cole

[Wine Slut]

I would call Rick Schell. He is the god of things that go "ring ding". Don't have his #, but he advrtises in rrw and cycle news.

[TZ925]

We successfully switched to Castrol A747 this weekend with no problems. I guess that debunks the myth of not switching premix oils in the middle of your crank life.

Monty

[Bill Cole]

Monty, I think that the oil switching is not a change and seize situation. I think it is just a shortening of the standard life of the internals. I am sure it will be fine however I would just keep an eye on the crank after 700miles. Just to be on the safe side. You wouldn't want to lock up that beautiful 00!

Bill C

[TwoCycler]

Monty,

I understand about all of the fears of oil impregnation into the metal and really have no argument there. Also, I have seen crank oil seals fail after 'living' with one type of oil for a long time and then switching.

I did a crank on one of my 2000 TZs this year, broke it in with Motul and then switched to Castrol TTS. Considering that I know of a number of AMA guys that have had crank bearing failures at the 500-700 mile mark on 2000-2001 TZs, my advice is to do it and not worry about it. You may get 1250 miles like I did on my last 2000 crank, or you may eat a bearing in 500+ miles like a few others have. The oil switch will probably not be the determining factor. Congrats on your new bike, although I am sorry to see Bill O. go.

Good luck,

Rocky Stargel