3tj crank bearing size info wanted

[KIYOSHI]

Anyone know the sizes for 3tj big end and crank journal bearings in relation to their colours?

Thanks

[Evilchicken0]

I think that's more a dealer question but you might find it in a parts book. If it's a used crank or different cases then you should plasti gauge it.

[KIYOSHI]

Yes plastigauge is the way forward but it's the specific size of the different shells I need to know so I can set the largest clearance on the big ends. Neither the yamaha manual or parts manual list specific sizes only clearances which might leave me doing a little trial and error work.

[dobbslc]

I got some info from BDK when I did mine. Can't remember what colour is biggest now but I think it was trial & error in the end to get it right.
PITA if you don't know what way to go though aint it!

[oollit]

I had the same problem trying to find out the shell sizes when I first started about rebuilding my 3TJ bottom end, and drew a blank.

I also gave BDK a call and also got told it was a trial and error affair.

To end up I was going to send them my engine and get the oil ways modified, oil pump modified and the shells matched. Can't remember the prices offhand, but it seemed reasonable at the time.

I ended up buying a 2nd hand engine instead of rebuilding my one.

The bike is still not running as the replacement engine wasn't up to much, so I am still unsure about what to do with it. Rebuild one good 400 out of the two 400 engines, or part out both 400's to fund a replacement 600.

[KIYOSHI]

Oolit, I'd be in the Market for those poorly 3tj engines, might even be able to do a deal on a thundercat lump??

[oollit]

That could be a possibility KIYOSHI.

Is it just the Thundercat lump that you have, or do you have the carbs, loom, ecu, etc. I was planning buying a complete Thundercat/FZR 600 and selling off the rest of the parts that I dont need, if I go down that route.

I was also going to pull the cylinder head off the replacement engine to see what the problem is, as I might get away with swopping over cylinder head from my other engine.

Hopefully I will have a bit more time on my hands in the new year to play with all my projects, now that I have eventually found a good mechanic to work at my garage.

[rrsp]

black shells are the biggest, if its a race motor you should put all blacks in the mains as they are not critticle, for more oil around the journals, as for the big-ends they are critticle in size and need to be correct if you cant see there colour on the side of the shell, you will have to plasti gauge them,unless you have a few diffrent colour shells to try, by seeing if they are to tight or to slack on the crank when tightend to the correct torq, thats from a ex bsb yamaha mechanic.

[dobbslc]

That's how I did mine it took me hours to get them all spot on. I set them on the looser side of the tolerence.
Don't know how many times I took the big end bolts out, cases apart etc.
I did use new bolts though just to be safe.