Valkyrie

Here's some pictures of my main bearings... they're a bit...worn.

I wonder if I should spend the extra cash for a three-window bearing.

(the pics are small but if you zoom in with a zoom function, you can see the copper showing through)

manslayerx9

from what i can see( not that much) they arent that bad. some might say that if any copper is showing to replace them, but i have heard that 20% copper showing is ok. i say that the 3 window is a waste for a street engine, if its going to be auto-x'ed or tracked then go with the 3 window.

RX7Tuner.

You will ruin the new bearing when you put it in. Use the old ones. If you're only going to use it for racing, worn bearings (as long as they aren't entirely copper) are better for that application than new ones.

Brian

initial D is REAL!

The bearing gets ruined? I saw the video on Pineapple racing and he seems to do it without damaging anything

Valkyrie

Definitely autocrossed...and eventually on the track.

The copper isn't nearly as slick as the surface coating is.

I'd say at least 25% is showing on the rear, and probably 20% on the front.

RX7Tuner.

Pressing in a new bearing on these engines is a very difficult thing to do correctly. To put a new one in with destroying it is difficult and you have to line up the tabs perfectly or the bearing will spin when under load. Without a lot of experience, (which I am guessing the OP does not have in replacing bearings) there is a high likelyhood he will install the bearing and think it looks right but will soon spin/fail because of improper installation. Pinneapple would have no trouble because they know what they are doing.

With 20-25% copper showing and with the application being a race track, his current bearings will be a perfect setup for him. The worn bearings will allow a thicker oil barrier between rotating parts which is ideal for consistent high revving rotary engines (excess of 8,000rpms).

Brian

Valkyrie

Well, I guess if the good news is that I can still use the bearings, the bad news is that I might need new rotor housings and side housings probably need to be lapped... nuts

My rear rotor was carboned up the wazoo. Haven't taken off the middle housing though.

Valkyrie

Both of the rotor housings are pretty chattered... I guess I can get them reground from JHB or look for some good used ones. The side housings definitely need to get lapped since they've got black rings around around them...

Also, I looked at the rear bearing and it's probably closer to 30 or 35% copper showing.

My clutch install is getting a wee bit expensive, to say the least (lol in a sad way).